diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2022-05-26 17:13:43 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2022-05-26 17:13:43 -0700 |
commit | ef98f9cfe20d8ca063365d46d4ab2b85eeeb324f (patch) | |
tree | fa7514a1db83eb01637db3cd7577d117e7dbcc6d /kernel | |
parent | 44d35720c9a660074b77ab9de37abf2c01c5b44f (diff) | |
parent | 7390b94a3c2d93272d6da4945b81a9cf78055b7b (diff) | |
download | linux-stable-ef98f9cfe20d8ca063365d46d4ab2b85eeeb324f.tar.gz linux-stable-ef98f9cfe20d8ca063365d46d4ab2b85eeeb324f.tar.bz2 linux-stable-ef98f9cfe20d8ca063365d46d4ab2b85eeeb324f.zip |
Merge tag 'modules-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux
Pull modules updates from Luis Chamberlain:
- It was time to tidy up kernel/module.c and one way of starting with
that effort was to split it up into files. At my request Aaron Tomlin
spearheaded that effort with the goal to not introduce any functional
at all during that endeavour. The penalty for the split is +1322
bytes total, +112 bytes in data, +1210 bytes in text while bss is
unchanged. One of the benefits of this other than helping make the
code easier to read and review is summoning more help on review for
changes with livepatching so kernel/module/livepatch.c is now pegged
as maintained by the live patching folks.
The before and after with just the move on a defconfig on x86-64:
$ size kernel/module.o
text data bss dec hex filename
38434 4540 104 43078 a846 kernel/module.o
$ size -t kernel/module/*.o
text data bss dec hex filename
4785 120 0 4905 1329 kernel/module/kallsyms.o
28577 4416 104 33097 8149 kernel/module/main.o
1158 8 0 1166 48e kernel/module/procfs.o
902 108 0 1010 3f2 kernel/module/strict_rwx.o
3390 0 0 3390 d3e kernel/module/sysfs.o
832 0 0 832 340 kernel/module/tree_lookup.o
39644 4652 104 44400 ad70 (TOTALS)
- Aaron added module unload taint tracking (MODULE_UNLOAD_TAINT_TRACKING),
to enable tracking unloaded modules which did taint the kernel.
- Christophe Leroy added CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
which lets architectures to request having modules data in vmalloc
area instead of module area. There are three reasons why an
architecture might want this:
a) On some architectures (like book3s/32) it is not possible to
protect against execution on a page basis. The exec stuff can be
mapped by different arch segment sizes (on book3s/32 that is 256M
segments). By default the module area is in an Exec segment while
vmalloc area is in a NoExec segment. Using vmalloc lets you muck
with module data as NoExec on those architectures whereas before
you could not.
b) By pushing more module data to vmalloc you also increase the
probability of module text to remain within a closer distance
from kernel core text and this reduces trampolines, this has been
reported on arm first and powerpc folks are following that lead.
c) Free'ing module_alloc() (Exec by default) area leaves this
exposed as Exec by default, some architectures have some security
enhancements to set this as NoExec on free, and splitting module
data with text let's future generic special allocators be added
to the kernel without having developers try to grok the tribal
knowledge per arch. Work like Rick Edgecombe's permission vmalloc
interface [0] becomes easier to address over time.
[0] https://lore.kernel.org/lkml/20201120202426.18009-1-rick.p.edgecombe@intel.com/#r
- Masahiro Yamada's symbol search enhancements
* tag 'modules-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux: (33 commits)
module: merge check_exported_symbol() into find_exported_symbol_in_section()
module: do not binary-search in __ksymtab_gpl if fsa->gplok is false
module: do not pass opaque pointer for symbol search
module: show disallowed symbol name for inherit_taint()
module: fix [e_shstrndx].sh_size=0 OOB access
module: Introduce module unload taint tracking
module: Move module_assert_mutex_or_preempt() to internal.h
module: Make module_flags_taint() accept a module's taints bitmap and usable outside core code
module.h: simplify MODULE_IMPORT_NS
powerpc: Select ARCH_WANTS_MODULES_DATA_IN_VMALLOC on book3s/32 and 8xx
module: Remove module_addr_min and module_addr_max
module: Add CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
module: Introduce data_layout
module: Prepare for handling several RB trees
module: Always have struct mod_tree_root
module: Rename debug_align() as strict_align()
module: Rework layout alignment to avoid BUG_ON()s
module: Move module_enable_x() and frob_text() in strict_rwx.c
module: Make module_enable_x() independent of CONFIG_ARCH_HAS_STRICT_MODULE_RWX
module: Move version support into a separate file
...
Diffstat (limited to 'kernel')
-rw-r--r-- | kernel/Makefile | 5 | ||||
-rw-r--r-- | kernel/debug/kdb/kdb_io.c | 1 | ||||
-rw-r--r-- | kernel/debug/kdb/kdb_keyboard.c | 1 | ||||
-rw-r--r-- | kernel/debug/kdb/kdb_main.c | 49 | ||||
-rw-r--r-- | kernel/debug/kdb/kdb_private.h | 4 | ||||
-rw-r--r-- | kernel/debug/kdb/kdb_support.c | 1 | ||||
-rw-r--r-- | kernel/module-internal.h | 50 | ||||
-rw-r--r-- | kernel/module/Makefile | 21 | ||||
-rw-r--r-- | kernel/module/debug_kmemleak.c | 30 | ||||
-rw-r--r-- | kernel/module/decompress.c (renamed from kernel/module_decompress.c) | 5 | ||||
-rw-r--r-- | kernel/module/internal.h | 302 | ||||
-rw-r--r-- | kernel/module/kallsyms.c | 512 | ||||
-rw-r--r-- | kernel/module/kdb.c | 62 | ||||
-rw-r--r-- | kernel/module/livepatch.c | 74 | ||||
-rw-r--r-- | kernel/module/main.c (renamed from kernel/module.c) | 1959 | ||||
-rw-r--r-- | kernel/module/procfs.c | 146 | ||||
-rw-r--r-- | kernel/module/signing.c | 122 | ||||
-rw-r--r-- | kernel/module/strict_rwx.c | 143 | ||||
-rw-r--r-- | kernel/module/sysfs.c | 436 | ||||
-rw-r--r-- | kernel/module/tracking.c | 61 | ||||
-rw-r--r-- | kernel/module/tree_lookup.c | 117 | ||||
-rw-r--r-- | kernel/module/version.c | 101 | ||||
-rw-r--r-- | kernel/module_signing.c | 45 |
23 files changed, 2276 insertions, 1971 deletions
diff --git a/kernel/Makefile b/kernel/Makefile index 847a82bfe0e3..318789c728d3 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -29,7 +29,6 @@ KCOV_INSTRUMENT_softirq.o := n KCSAN_SANITIZE_softirq.o = n # These are called from save_stack_trace() on slub debug path, # and produce insane amounts of uninteresting coverage. -KCOV_INSTRUMENT_module.o := n KCOV_INSTRUMENT_extable.o := n KCOV_INSTRUMENT_stacktrace.o := n # Don't self-instrument. @@ -53,6 +52,7 @@ obj-y += rcu/ obj-y += livepatch/ obj-y += dma/ obj-y += entry/ +obj-$(CONFIG_MODULES) += module/ obj-$(CONFIG_KCMP) += kcmp.o obj-$(CONFIG_FREEZER) += freezer.o @@ -66,9 +66,6 @@ ifneq ($(CONFIG_SMP),y) obj-y += up.o endif obj-$(CONFIG_UID16) += uid16.o -obj-$(CONFIG_MODULES) += module.o -obj-$(CONFIG_MODULE_DECOMPRESS) += module_decompress.o -obj-$(CONFIG_MODULE_SIG) += module_signing.o obj-$(CONFIG_MODULE_SIG_FORMAT) += module_signature.o obj-$(CONFIG_KALLSYMS) += kallsyms.o obj-$(CONFIG_BSD_PROCESS_ACCT) += acct.o diff --git a/kernel/debug/kdb/kdb_io.c b/kernel/debug/kdb/kdb_io.c index 6735ac36b718..67d3c48a1522 100644 --- a/kernel/debug/kdb/kdb_io.c +++ b/kernel/debug/kdb/kdb_io.c @@ -9,7 +9,6 @@ * Copyright (c) 2009 Wind River Systems, Inc. All Rights Reserved. */ -#include <linux/module.h> #include <linux/types.h> #include <linux/ctype.h> #include <linux/kernel.h> diff --git a/kernel/debug/kdb/kdb_keyboard.c b/kernel/debug/kdb/kdb_keyboard.c index f877a0a0d7cf..f87c750d3eb3 100644 --- a/kernel/debug/kdb/kdb_keyboard.c +++ b/kernel/debug/kdb/kdb_keyboard.c @@ -11,7 +11,6 @@ #include <linux/kdb.h> #include <linux/keyboard.h> #include <linux/ctype.h> -#include <linux/module.h> #include <linux/io.h> /* Keyboard Controller Registers on normal PCs. */ diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c index ead4da947127..438b868cbfa9 100644 --- a/kernel/debug/kdb/kdb_main.c +++ b/kernel/debug/kdb/kdb_main.c @@ -26,7 +26,6 @@ #include <linux/utsname.h> #include <linux/vmalloc.h> #include <linux/atomic.h> -#include <linux/module.h> #include <linux/moduleparam.h> #include <linux/mm.h> #include <linux/init.h> @@ -2060,54 +2059,6 @@ static int kdb_ef(int argc, const char **argv) return 0; } -#if defined(CONFIG_MODULES) -/* - * kdb_lsmod - This function implements the 'lsmod' command. Lists - * currently loaded kernel modules. - * Mostly taken from userland lsmod. - */ -static int kdb_lsmod(int argc, const char **argv) -{ - struct module *mod; - - if (argc != 0) - return KDB_ARGCOUNT; - - kdb_printf("Module Size modstruct Used by\n"); - list_for_each_entry(mod, kdb_modules, list) { - if (mod->state == MODULE_STATE_UNFORMED) - continue; - - kdb_printf("%-20s%8u 0x%px ", mod->name, - mod->core_layout.size, (void *)mod); -#ifdef CONFIG_MODULE_UNLOAD - kdb_printf("%4d ", module_refcount(mod)); -#endif - if (mod->state == MODULE_STATE_GOING) - kdb_printf(" (Unloading)"); - else if (mod->state == MODULE_STATE_COMING) - kdb_printf(" (Loading)"); - else - kdb_printf(" (Live)"); - kdb_printf(" 0x%px", mod->core_layout.base); - -#ifdef CONFIG_MODULE_UNLOAD - { - struct module_use *use; - kdb_printf(" [ "); - list_for_each_entry(use, &mod->source_list, - source_list) - kdb_printf("%s ", use->target->name); - kdb_printf("]\n"); - } -#endif - } - - return 0; -} - -#endif /* CONFIG_MODULES */ - /* * kdb_env - This function implements the 'env' command. Display the * current environment variables. diff --git a/kernel/debug/kdb/kdb_private.h b/kernel/debug/kdb/kdb_private.h index 0d2f9feea0a4..1f8c519a5f81 100644 --- a/kernel/debug/kdb/kdb_private.h +++ b/kernel/debug/kdb/kdb_private.h @@ -226,10 +226,6 @@ extern void kdb_kbd_cleanup_state(void); #define kdb_kbd_cleanup_state() #endif /* ! CONFIG_KDB_KEYBOARD */ -#ifdef CONFIG_MODULES -extern struct list_head *kdb_modules; -#endif /* CONFIG_MODULES */ - extern char kdb_prompt_str[]; #define KDB_WORD_SIZE ((int)sizeof(unsigned long)) diff --git a/kernel/debug/kdb/kdb_support.c b/kernel/debug/kdb/kdb_support.c index 85cb51c4a17e..0a39497140bf 100644 --- a/kernel/debug/kdb/kdb_support.c +++ b/kernel/debug/kdb/kdb_support.c @@ -17,7 +17,6 @@ #include <linux/stddef.h> #include <linux/vmalloc.h> #include <linux/ptrace.h> -#include <linux/module.h> #include <linux/highmem.h> #include <linux/hardirq.h> #include <linux/delay.h> diff --git a/kernel/module-internal.h b/kernel/module-internal.h deleted file mode 100644 index 8c381c99062f..000000000000 --- a/kernel/module-internal.h +++ /dev/null @@ -1,50 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0-or-later */ -/* Module internals - * - * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved. - * Written by David Howells (dhowells@redhat.com) - */ - -#include <linux/elf.h> -#include <asm/module.h> - -struct load_info { - const char *name; - /* pointer to module in temporary copy, freed at end of load_module() */ - struct module *mod; - Elf_Ehdr *hdr; - unsigned long len; - Elf_Shdr *sechdrs; - char *secstrings, *strtab; - unsigned long symoffs, stroffs, init_typeoffs, core_typeoffs; - struct _ddebug *debug; - unsigned int num_debug; - bool sig_ok; -#ifdef CONFIG_KALLSYMS - unsigned long mod_kallsyms_init_off; -#endif -#ifdef CONFIG_MODULE_DECOMPRESS - struct page **pages; - unsigned int max_pages; - unsigned int used_pages; -#endif - struct { - unsigned int sym, str, mod, vers, info, pcpu; - } index; -}; - -extern int mod_verify_sig(const void *mod, struct load_info *info); - -#ifdef CONFIG_MODULE_DECOMPRESS -int module_decompress(struct load_info *info, const void *buf, size_t size); -void module_decompress_cleanup(struct load_info *info); -#else -static inline int module_decompress(struct load_info *info, - const void *buf, size_t size) -{ - return -EOPNOTSUPP; -} -static inline void module_decompress_cleanup(struct load_info *info) -{ -} -#endif diff --git a/kernel/module/Makefile b/kernel/module/Makefile new file mode 100644 index 000000000000..948efea81e85 --- /dev/null +++ b/kernel/module/Makefile @@ -0,0 +1,21 @@ +# SPDX-License-Identifier: GPL-2.0-only +# +# Makefile for linux kernel module support +# + +# These are called from save_stack_trace() on slub debug path, +# and produce insane amounts of uninteresting coverage. +KCOV_INSTRUMENT_module.o := n + +obj-y += main.o strict_rwx.o +obj-$(CONFIG_MODULE_DECOMPRESS) += decompress.o +obj-$(CONFIG_MODULE_SIG) += signing.o +obj-$(CONFIG_LIVEPATCH) += livepatch.o +obj-$(CONFIG_MODULES_TREE_LOOKUP) += tree_lookup.o +obj-$(CONFIG_DEBUG_KMEMLEAK) += debug_kmemleak.o +obj-$(CONFIG_KALLSYMS) += kallsyms.o +obj-$(CONFIG_PROC_FS) += procfs.o +obj-$(CONFIG_SYSFS) += sysfs.o +obj-$(CONFIG_KGDB_KDB) += kdb.o +obj-$(CONFIG_MODVERSIONS) += version.o +obj-$(CONFIG_MODULE_UNLOAD_TAINT_TRACKING) += tracking.o diff --git a/kernel/module/debug_kmemleak.c b/kernel/module/debug_kmemleak.c new file mode 100644 index 000000000000..12a569d361e8 --- /dev/null +++ b/kernel/module/debug_kmemleak.c @@ -0,0 +1,30 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Module kmemleak support + * + * Copyright (C) 2009 Catalin Marinas + */ + +#include <linux/module.h> +#include <linux/kmemleak.h> +#include "internal.h" + +void kmemleak_load_module(const struct module *mod, + const struct load_info *info) +{ + unsigned int i; + + /* only scan the sections containing data */ + kmemleak_scan_area(mod, sizeof(struct module), GFP_KERNEL); + + for (i = 1; i < info->hdr->e_shnum; i++) { + /* Scan all writable sections that's not executable */ + if (!(info->sechdrs[i].sh_flags & SHF_ALLOC) || + !(info->sechdrs[i].sh_flags & SHF_WRITE) || + (info->sechdrs[i].sh_flags & SHF_EXECINSTR)) + continue; + + kmemleak_scan_area((void *)info->sechdrs[i].sh_addr, + info->sechdrs[i].sh_size, GFP_KERNEL); + } +} diff --git a/kernel/module_decompress.c b/kernel/module/decompress.c index ffef98a20320..2fc7081dd7c1 100644 --- a/kernel/module_decompress.c +++ b/kernel/module/decompress.c @@ -12,7 +12,7 @@ #include <linux/sysfs.h> #include <linux/vmalloc.h> -#include "module-internal.h" +#include "internal.h" static int module_extend_max_pages(struct load_info *info, unsigned int extent) { @@ -113,6 +113,7 @@ static ssize_t module_gzip_decompress(struct load_info *info, do { struct page *page = module_get_next_page(info); + if (!page) { retval = -ENOMEM; goto out_inflate_end; @@ -171,6 +172,7 @@ static ssize_t module_xz_decompress(struct load_info *info, do { struct page *page = module_get_next_page(info); + if (!page) { retval = -ENOMEM; goto out; @@ -256,6 +258,7 @@ static ssize_t compression_show(struct kobject *kobj, { return sysfs_emit(buf, "%s\n", __stringify(MODULE_COMPRESSION)); } + static struct kobj_attribute module_compression_attr = __ATTR_RO(compression); static int __init module_decompress_sysfs_init(void) diff --git a/kernel/module/internal.h b/kernel/module/internal.h new file mode 100644 index 000000000000..bc5507ab8450 --- /dev/null +++ b/kernel/module/internal.h @@ -0,0 +1,302 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* Module internals + * + * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + */ + +#include <linux/elf.h> +#include <linux/compiler.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/rculist.h> +#include <linux/rcupdate.h> + +#ifndef ARCH_SHF_SMALL +#define ARCH_SHF_SMALL 0 +#endif + +/* If this is set, the section belongs in the init part of the module */ +#define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG - 1)) +/* Maximum number of characters written by module_flags() */ +#define MODULE_FLAGS_BUF_SIZE (TAINT_FLAGS_COUNT + 4) + +#ifndef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC +#define data_layout core_layout +#endif + +/* + * Modules' sections will be aligned on page boundaries + * to ensure complete separation of code and data, but + * only when CONFIG_STRICT_MODULE_RWX=y + */ +#ifdef CONFIG_STRICT_MODULE_RWX +# define strict_align(X) PAGE_ALIGN(X) +#else +# define strict_align(X) (X) +#endif + +extern struct mutex module_mutex; +extern struct list_head modules; + +extern struct module_attribute *modinfo_attrs[]; +extern size_t modinfo_attrs_count; + +/* Provided by the linker */ +extern const struct kernel_symbol __start___ksymtab[]; +extern const struct kernel_symbol __stop___ksymtab[]; +extern const struct kernel_symbol __start___ksymtab_gpl[]; +extern const struct kernel_symbol __stop___ksymtab_gpl[]; +extern const s32 __start___kcrctab[]; +extern const s32 __start___kcrctab_gpl[]; + +struct load_info { + const char *name; + /* pointer to module in temporary copy, freed at end of load_module() */ + struct module *mod; + Elf_Ehdr *hdr; + unsigned long len; + Elf_Shdr *sechdrs; + char *secstrings, *strtab; + unsigned long symoffs, stroffs, init_typeoffs, core_typeoffs; + struct _ddebug *debug; + unsigned int num_debug; + bool sig_ok; +#ifdef CONFIG_KALLSYMS + unsigned long mod_kallsyms_init_off; +#endif +#ifdef CONFIG_MODULE_DECOMPRESS + struct page **pages; + unsigned int max_pages; + unsigned int used_pages; +#endif + struct { + unsigned int sym, str, mod, vers, info, pcpu; + } index; +}; + +enum mod_license { + NOT_GPL_ONLY, + GPL_ONLY, +}; + +struct find_symbol_arg { + /* Input */ + const char *name; + bool gplok; + bool warn; + + /* Output */ + struct module *owner; + const s32 *crc; + const struct kernel_symbol *sym; + enum mod_license license; +}; + +int mod_verify_sig(const void *mod, struct load_info *info); +int try_to_force_load(struct module *mod, const char *reason); +bool find_symbol(struct find_symbol_arg *fsa); +struct module *find_module_all(const char *name, size_t len, bool even_unformed); +int cmp_name(const void *name, const void *sym); +long module_get_offset(struct module *mod, unsigned int *size, Elf_Shdr *sechdr, + unsigned int section); +char *module_flags(struct module *mod, char *buf); +size_t module_flags_taint(unsigned long taints, char *buf); + +static inline void module_assert_mutex_or_preempt(void) +{ +#ifdef CONFIG_LOCKDEP + if (unlikely(!debug_locks)) + return; + + WARN_ON_ONCE(!rcu_read_lock_sched_held() && + !lockdep_is_held(&module_mutex)); +#endif +} + +static inline unsigned long kernel_symbol_value(const struct kernel_symbol *sym) +{ +#ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS + return (unsigned long)offset_to_ptr(&sym->value_offset); +#else + return sym->value; +#endif +} + +#ifdef CONFIG_LIVEPATCH +int copy_module_elf(struct module *mod, struct load_info *info); +void free_module_elf(struct module *mod); +#else /* !CONFIG_LIVEPATCH */ +static inline int copy_module_elf(struct module *mod, struct load_info *info) +{ + return 0; +} + +static inline void free_module_elf(struct module *mod) { } +#endif /* CONFIG_LIVEPATCH */ + +static inline bool set_livepatch_module(struct module *mod) +{ +#ifdef CONFIG_LIVEPATCH + mod->klp = true; + return true; +#else + return false; +#endif +} + +#ifdef CONFIG_MODULE_UNLOAD_TAINT_TRACKING +struct mod_unload_taint { + struct list_head list; + char name[MODULE_NAME_LEN]; + unsigned long taints; + u64 count; +}; + +int try_add_tainted_module(struct module *mod); +void print_unloaded_tainted_modules(void); +#else /* !CONFIG_MODULE_UNLOAD_TAINT_TRACKING */ +static inline int try_add_tainted_module(struct module *mod) +{ + return 0; +} + +static inline void print_unloaded_tainted_modules(void) +{ +} +#endif /* CONFIG_MODULE_UNLOAD_TAINT_TRACKING */ + +#ifdef CONFIG_MODULE_DECOMPRESS +int module_decompress(struct load_info *info, const void *buf, size_t size); +void module_decompress_cleanup(struct load_info *info); +#else +static inline int module_decompress(struct load_info *info, + const void *buf, size_t size) +{ + return -EOPNOTSUPP; +} + +static inline void module_decompress_cleanup(struct load_info *info) +{ +} +#endif + +struct mod_tree_root { +#ifdef CONFIG_MODULES_TREE_LOOKUP + struct latch_tree_root root; +#endif + unsigned long addr_min; + unsigned long addr_max; +}; + +extern struct mod_tree_root mod_tree; +extern struct mod_tree_root mod_data_tree; + +#ifdef CONFIG_MODULES_TREE_LOOKUP +void mod_tree_insert(struct module *mod); +void mod_tree_remove_init(struct module *mod); +void mod_tree_remove(struct module *mod); +struct module *mod_find(unsigned long addr, struct mod_tree_root *tree); +#else /* !CONFIG_MODULES_TREE_LOOKUP */ + +static inline void mod_tree_insert(struct module *mod) { } +static inline void mod_tree_remove_init(struct module *mod) { } +static inline void mod_tree_remove(struct module *mod) { } +static inline struct module *mod_find(unsigned long addr, struct mod_tree_root *tree) +{ + struct module *mod; + + list_for_each_entry_rcu(mod, &modules, list, + lockdep_is_held(&module_mutex)) { + if (within_module(addr, mod)) + return mod; + } + + return NULL; +} +#endif /* CONFIG_MODULES_TREE_LOOKUP */ + +void module_enable_ro(const struct module *mod, bool after_init); +void module_enable_nx(const struct module *mod); +void module_enable_x(const struct module *mod); +int module_enforce_rwx_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs, + char *secstrings, struct module *mod); +bool module_check_misalignment(const struct module *mod); + +#ifdef CONFIG_MODULE_SIG +int module_sig_check(struct load_info *info, int flags); +#else /* !CONFIG_MODULE_SIG */ +static inline int module_sig_check(struct load_info *info, int flags) +{ + return 0; +} +#endif /* !CONFIG_MODULE_SIG */ + +#ifdef CONFIG_DEBUG_KMEMLEAK +void kmemleak_load_module(const struct module *mod, const struct load_info *info); +#else /* !CONFIG_DEBUG_KMEMLEAK */ +static inline void kmemleak_load_module(const struct module *mod, + const struct load_info *info) { } +#endif /* CONFIG_DEBUG_KMEMLEAK */ + +#ifdef CONFIG_KALLSYMS +void init_build_id(struct module *mod, const struct load_info *info); +void layout_symtab(struct module *mod, struct load_info *info); +void add_kallsyms(struct module *mod, const struct load_info *info); +unsigned long find_kallsyms_symbol_value(struct module *mod, const char *name); + +static inline bool sect_empty(const Elf_Shdr *sect) +{ + return !(sect->sh_flags & SHF_ALLOC) || sect->sh_size == 0; +} +#else /* !CONFIG_KALLSYMS */ +static inline void init_build_id(struct module *mod, const struct load_info *info) { } +static inline void layout_symtab(struct module *mod, struct load_info *info) { } +static inline void add_kallsyms(struct module *mod, const struct load_info *info) { } +#endif /* CONFIG_KALLSYMS */ + +#ifdef CONFIG_SYSFS +int mod_sysfs_setup(struct module *mod, const struct load_info *info, + struct kernel_param *kparam, unsigned int num_params); +void mod_sysfs_teardown(struct module *mod); +void init_param_lock(struct module *mod); +#else /* !CONFIG_SYSFS */ +static inline int mod_sysfs_setup(struct module *mod, + const struct load_info *info, + struct kernel_param *kparam, + unsigned int num_params) +{ + return 0; +} + +static inline void mod_sysfs_teardown(struct module *mod) { } +static inline void init_param_lock(struct module *mod) { } +#endif /* CONFIG_SYSFS */ + +#ifdef CONFIG_MODVERSIONS +int check_version(const struct load_info *info, + const char *symname, struct module *mod, const s32 *crc); +void module_layout(struct module *mod, struct modversion_info *ver, struct kernel_param *kp, + struct kernel_symbol *ks, struct tracepoint * const *tp); +int check_modstruct_version(const struct load_info *info, struct module *mod); +int same_magic(const char *amagic, const char *bmagic, bool has_crcs); +#else /* !CONFIG_MODVERSIONS */ +static inline int check_version(const struct load_info *info, + const char *symname, + struct module *mod, + const s32 *crc) +{ + return 1; +} + +static inline int check_modstruct_version(const struct load_info *info, + struct module *mod) +{ + return 1; +} + +static inline int same_magic(const char *amagic, const char *bmagic, bool has_crcs) +{ + return strcmp(amagic, bmagic) == 0; +} +#endif /* CONFIG_MODVERSIONS */ diff --git a/kernel/module/kallsyms.c b/kernel/module/kallsyms.c new file mode 100644 index 000000000000..3e11523bc6f6 --- /dev/null +++ b/kernel/module/kallsyms.c @@ -0,0 +1,512 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Module kallsyms support + * + * Copyright (C) 2010 Rusty Russell + */ + +#include <linux/module.h> +#include <linux/kallsyms.h> +#include <linux/buildid.h> +#include <linux/bsearch.h> +#include "internal.h" + +/* Lookup exported symbol in given range of kernel_symbols */ +static const struct kernel_symbol *lookup_exported_symbol(const char *name, + const struct kernel_symbol *start, + const struct kernel_symbol *stop) +{ + return bsearch(name, start, stop - start, + sizeof(struct kernel_symbol), cmp_name); +} + +static int is_exported(const char *name, unsigned long value, + const struct module *mod) +{ + const struct kernel_symbol *ks; + + if (!mod) + ks = lookup_exported_symbol(name, __start___ksymtab, __stop___ksymtab); + else + ks = lookup_exported_symbol(name, mod->syms, mod->syms + mod->num_syms); + + return ks && kernel_symbol_value(ks) == value; +} + +/* As per nm */ +static char elf_type(const Elf_Sym *sym, const struct load_info *info) +{ + const Elf_Shdr *sechdrs = info->sechdrs; + + if (ELF_ST_BIND(sym->st_info) == STB_WEAK) { + if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT) + return 'v'; + else + return 'w'; + } + if (sym->st_shndx == SHN_UNDEF) + return 'U'; + if (sym->st_shndx == SHN_ABS || sym->st_shndx == info->index.pcpu) + return 'a'; + if (sym->st_shndx >= SHN_LORESERVE) + return '?'; + if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR) + return 't'; + if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC && + sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) { + if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE)) + return 'r'; + else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL) + return 'g'; + else + return 'd'; + } + if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) { + if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL) + return 's'; + else + return 'b'; + } + if (strstarts(info->secstrings + sechdrs[sym->st_shndx].sh_name, + ".debug")) { + return 'n'; + } + return '?'; +} + +static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs, + unsigned int shnum, unsigned int pcpundx) +{ + const Elf_Shdr *sec; + + if (src->st_shndx == SHN_UNDEF || + src->st_shndx >= shnum || + !src->st_name) + return false; + +#ifdef CONFIG_KALLSYMS_ALL + if (src->st_shndx == pcpundx) + return true; +#endif + + sec = sechdrs + src->st_shndx; + if (!(sec->sh_flags & SHF_ALLOC) +#ifndef CONFIG_KALLSYMS_ALL + || !(sec->sh_flags & SHF_EXECINSTR) +#endif + || (sec->sh_entsize & INIT_OFFSET_MASK)) + return false; + + return true; +} + +/* + * We only allocate and copy the strings needed by the parts of symtab + * we keep. This is simple, but has the effect of making multiple + * copies of duplicates. We could be more sophisticated, see + * linux-kernel thread starting with + * <73defb5e4bca04a6431392cc341112b1@localhost>. + */ +void layout_symtab(struct module *mod, struct load_info *info) +{ + Elf_Shdr *symsect = info->sechdrs + info->index.sym; + Elf_Shdr *strsect = info->sechdrs + info->index.str; + const Elf_Sym *src; + unsigned int i, nsrc, ndst, strtab_size = 0; + + /* Put symbol section at end of init part of module. */ + symsect->sh_flags |= SHF_ALLOC; + symsect->sh_entsize = module_get_offset(mod, &mod->init_layout.size, symsect, + info->index.sym) | INIT_OFFSET_MASK; + pr_debug("\t%s\n", info->secstrings + symsect->sh_name); + + src = (void *)info->hdr + symsect->sh_offset; + nsrc = symsect->sh_size / sizeof(*src); + + /* Compute total space required for the core symbols' strtab. */ + for (ndst = i = 0; i < nsrc; i++) { + if (i == 0 || is_livepatch_module(mod) || + is_core_symbol(src + i, info->sechdrs, info->hdr->e_shnum, + info->index.pcpu)) { + strtab_size += strlen(&info->strtab[src[i].st_name]) + 1; + ndst++; + } + } + + /* Append room for core symbols at end of core part. */ + info->symoffs = ALIGN(mod->data_layout.size, symsect->sh_addralign ?: 1); + info->stroffs = mod->data_layout.size = info->symoffs + ndst * sizeof(Elf_Sym); + mod->data_layout.size += strtab_size; + info->core_typeoffs = mod->data_layout.size; + mod->data_layout.size += ndst * sizeof(char); + mod->data_layout.size = strict_align(mod->data_layout.size); + + /* Put string table section at end of init part of module. */ + strsect->sh_flags |= SHF_ALLOC; + strsect->sh_entsize = module_get_offset(mod, &mod->init_layout.size, strsect, + info->index.str) | INIT_OFFSET_MASK; + pr_debug("\t%s\n", info->secstrings + strsect->sh_name); + + /* We'll tack temporary mod_kallsyms on the end. */ + mod->init_layout.size = ALIGN(mod->init_layout.size, + __alignof__(struct mod_kallsyms)); + info->mod_kallsyms_init_off = mod->init_layout.size; + mod->init_layout.size += sizeof(struct mod_kallsyms); + info->init_typeoffs = mod->init_layout.size; + mod->init_layout.size += nsrc * sizeof(char); + mod->init_layout.size = strict_align(mod->init_layout.size); +} + +/* + * We use the full symtab and strtab which layout_symtab arranged to + * be appended to the init section. Later we switch to the cut-down + * core-only ones. + */ +void add_kallsyms(struct module *mod, const struct load_info *info) +{ + unsigned int i, ndst; + const Elf_Sym *src; + Elf_Sym *dst; + char *s; + Elf_Shdr *symsec = &info->sechdrs[info->index.sym]; + + /* Set up to point into init section. */ + mod->kallsyms = (void __rcu *)mod->init_layout.base + + info->mod_kallsyms_init_off; + + preempt_disable(); + /* The following is safe since this pointer cannot change */ + rcu_dereference_sched(mod->kallsyms)->symtab = (void *)symsec->sh_addr; + rcu_dereference_sched(mod->kallsyms)->num_symtab = symsec->sh_size / sizeof(Elf_Sym); + /* Make sure we get permanent strtab: don't use info->strtab. */ + rcu_dereference_sched(mod->kallsyms)->strtab = + (void *)info->sechdrs[info->index.str].sh_addr; + rcu_dereference_sched(mod->kallsyms)->typetab = mod->init_layout.base + info->init_typeoffs; + + /* + * Now populate the cut down core kallsyms for after init + * and set types up while we still have access to sections. + */ + mod->core_kallsyms.symtab = dst = mod->data_layout.base + info->symoffs; + mod->core_kallsyms.strtab = s = mod->data_layout.base + info->stroffs; + mod->core_kallsyms.typetab = mod->data_layout.base + info->core_typeoffs; + src = rcu_dereference_sched(mod->kallsyms)->symtab; + for (ndst = i = 0; i < rcu_dereference_sched(mod->kallsyms)->num_symtab; i++) { + rcu_dereference_sched(mod->kallsyms)->typetab[i] = elf_type(src + i, info); + if (i == 0 || is_livepatch_module(mod) || + is_core_symbol(src + i, info->sechdrs, info->hdr->e_shnum, + info->index.pcpu)) { + mod->core_kallsyms.typetab[ndst] = + rcu_dereference_sched(mod->kallsyms)->typetab[i]; + dst[ndst] = src[i]; + dst[ndst++].st_name = s - mod->core_kallsyms.strtab; + s += strscpy(s, + &rcu_dereference_sched(mod->kallsyms)->strtab[src[i].st_name], + KSYM_NAME_LEN) + 1; + } + } + preempt_enable(); + mod->core_kallsyms.num_symtab = ndst; +} + +#if IS_ENABLED(CONFIG_STACKTRACE_BUILD_ID) +void init_build_id(struct module *mod, const struct load_info *info) +{ + const Elf_Shdr *sechdr; + unsigned int i; + + for (i = 0; i < info->hdr->e_shnum; i++) { + sechdr = &info->sechdrs[i]; + if (!sect_empty(sechdr) && sechdr->sh_type == SHT_NOTE && + !build_id_parse_buf((void *)sechdr->sh_addr, mod->build_id, + sechdr->sh_size)) + break; + } +} +#else +void init_build_id(struct module *mod, const struct load_info *info) +{ +} +#endif + +/* + * This ignores the intensely annoying "mapping symbols" found + * in ARM ELF files: $a, $t and $d. + */ +static inline int is_arm_mapping_symbol(const char *str) +{ + if (str[0] == '.' && str[1] == 'L') + return true; + return str[0] == '$' && strchr("axtd", str[1]) && + (str[2] == '\0' || str[2] == '.'); +} + +static const char *kallsyms_symbol_name(struct mod_kallsyms *kallsyms, unsigned int symnum) +{ + return kallsyms->strtab + kallsyms->symtab[symnum].st_name; +} + +/* + * Given a module and address, find the corresponding symbol and return its name + * while providing its size and offset if needed. + */ +static const char *find_kallsyms_symbol(struct module *mod, + unsigned long addr, + unsigned long *size, + unsigned long *offset) +{ + unsigned int i, best = 0; + unsigned long nextval, bestval; + struct mod_kallsyms *kallsyms = rcu_dereference_sched(mod->kallsyms); + + /* At worse, next value is at end of module */ + if (within_module_init(addr, mod)) + nextval = (unsigned long)mod->init_layout.base + mod->init_layout.text_size; + else + nextval = (unsigned long)mod->core_layout.base + mod->core_layout.text_size; + + bestval = kallsyms_symbol_value(&kallsyms->symtab[best]); + + /* + * Scan for closest preceding symbol, and next symbol. (ELF + * starts real symbols at 1). + */ + for (i = 1; i < kallsyms->num_symtab; i++) { + const Elf_Sym *sym = &kallsyms->symtab[i]; + unsigned long thisval = kallsyms_symbol_value(sym); + + if (sym->st_shndx == SHN_UNDEF) + continue; + + /* + * We ignore unnamed symbols: they're uninformative + * and inserted at a whim. + */ + if (*kallsyms_symbol_name(kallsyms, i) == '\0' || + is_arm_mapping_symbol(kallsyms_symbol_name(kallsyms, i))) + continue; + + if (thisval <= addr && thisval > bestval) { + best = i; + bestval = thisval; + } + if (thisval > addr && thisval < nextval) + nextval = thisval; + } + + if (!best) + return NULL; + + if (size) + *size = nextval - bestval; + if (offset) + *offset = addr - bestval; + + return kallsyms_symbol_name(kallsyms, best); +} + +void * __weak dereference_module_function_descriptor(struct module *mod, + void *ptr) +{ + return ptr; +} + +/* + * For kallsyms to ask for address resolution. NULL means not found. Careful + * not to lock to avoid deadlock on oopses, simply disable preemption. + */ +const char *module_address_lookup(unsigned long addr, + unsigned long *size, + unsigned long *offset, + char **modname, + const unsigned char **modbuildid, + char *namebuf) +{ + const char *ret = NULL; + struct module *mod; + + preempt_disable(); + mod = __module_address(addr); + if (mod) { + if (modname) + *modname = mod->name; + if (modbuildid) { +#if IS_ENABLED(CONFIG_STACKTRACE_BUILD_ID) + *modbuildid = mod->build_id; +#else + *modbuildid = NULL; +#endif + } + + ret = find_kallsyms_symbol(mod, addr, size, offset); + } + /* Make a copy in here where it's safe */ + if (ret) { + strncpy(namebuf, ret, KSYM_NAME_LEN - 1); + ret = namebuf; + } + preempt_enable(); + + return ret; +} + +int lookup_module_symbol_name(unsigned long addr, char *symname) +{ + struct module *mod; + + preempt_disable(); + list_for_each_entry_rcu(mod, &modules, list) { + if (mod->state == MODULE_STATE_UNFORMED) + continue; + if (within_module(addr, mod)) { + const char *sym; + + sym = find_kallsyms_symbol(mod, addr, NULL, NULL); + if (!sym) + goto out; + + strscpy(symname, sym, KSYM_NAME_LEN); + preempt_enable(); + return 0; + } + } +out: + preempt_enable(); + return -ERANGE; +} + +int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size, + unsigned long *offset, char *modname, char *name) +{ + struct module *mod; + + preempt_disable(); + list_for_each_entry_rcu(mod, &modules, list) { + if (mod->state == MODULE_STATE_UNFORMED) + continue; + if (within_module(addr, mod)) { + const char *sym; + + sym = find_kallsyms_symbol(mod, addr, size, offset); + if (!sym) + goto out; + if (modname) + strscpy(modname, mod->name, MODULE_NAME_LEN); + if (name) + strscpy(name, sym, KSYM_NAME_LEN); + preempt_enable(); + return 0; + } + } +out: + preempt_enable(); + return -ERANGE; +} + +int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type, + char *name, char *module_name, int *exported) +{ + struct module *mod; + + preempt_disable(); + list_for_each_entry_rcu(mod, &modules, list) { + struct mod_kallsyms *kallsyms; + + if (mod->state == MODULE_STATE_UNFORMED) + continue; + kallsyms = rcu_dereference_sched(mod->kallsyms); + if (symnum < kallsyms->num_symtab) { + const Elf_Sym *sym = &kallsyms->symtab[symnum]; + + *value = kallsyms_symbol_value(sym); + *type = kallsyms->typetab[symnum]; + strscpy(name, kallsyms_symbol_name(kallsyms, symnum), KSYM_NAME_LEN); + strscpy(module_name, mod->name, MODULE_NAME_LEN); + *exported = is_exported(name, *value, mod); + preempt_enable(); + return 0; + } + symnum -= kallsyms->num_symtab; + } + preempt_enable(); + return -ERANGE; +} + +/* Given a module and name of symbol, find and return the symbol's value */ +unsigned long find_kallsyms_symbol_value(struct module *mod, const char *name) +{ + unsigned int i; + struct mod_kallsyms *kallsyms = rcu_dereference_sched(mod->kallsyms); + + for (i = 0; i < kallsyms->num_symtab; i++) { + const Elf_Sym *sym = &kallsyms->symtab[i]; + + if (strcmp(name, kallsyms_symbol_name(kallsyms, i)) == 0 && + sym->st_shndx != SHN_UNDEF) + return kallsyms_symbol_value(sym); + } + return 0; +} + +/* Look for this name: can be of form module:name. */ +unsigned long module_kallsyms_lookup_name(const char *name) +{ + struct module *mod; + char *colon; + unsigned long ret = 0; + + /* Don't lock: we're in enough trouble already. */ + preempt_disable(); + if ((colon = strnchr(name, MODULE_NAME_LEN, ':')) != NULL) { + if ((mod = find_module_all(name, colon - name, false)) != NULL) + ret = find_kallsyms_symbol_value(mod, colon + 1); + } else { + list_for_each_entry_rcu(mod, &modules, list) { + if (mod->state == MODULE_STATE_UNFORMED) + continue; + if ((ret = find_kallsyms_symbol_value(mod, name)) != 0) + break; + } + } + preempt_enable(); + return ret; +} + +#ifdef CONFIG_LIVEPATCH +int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *, + struct module *, unsigned long), + void *data) +{ + struct module *mod; + unsigned int i; + int ret = 0; + + mutex_lock(&module_mutex); + list_for_each_entry(mod, &modules, list) { + struct mod_kallsyms *kallsyms; + + if (mod->state == MODULE_STATE_UNFORMED) + continue; + + /* Use rcu_dereference_sched() to remain compliant with the sparse tool */ + preempt_disable(); + kallsyms = rcu_dereference_sched(mod->kallsyms); + preempt_enable(); + + for (i = 0; i < kallsyms->num_symtab; i++) { + const Elf_Sym *sym = &kallsyms->symtab[i]; + + if (sym->st_shndx == SHN_UNDEF) + continue; + + ret = fn(data, kallsyms_symbol_name(kallsyms, i), + mod, kallsyms_symbol_value(sym)); + if (ret != 0) + goto out; + } + } +out: + mutex_unlock(&module_mutex); + return ret; +} +#endif /* CONFIG_LIVEPATCH */ diff --git a/kernel/module/kdb.c b/kernel/module/kdb.c new file mode 100644 index 000000000000..f4317f92e189 --- /dev/null +++ b/kernel/module/kdb.c @@ -0,0 +1,62 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Module kdb support + * + * Copyright (C) 2010 Jason Wessel + */ + +#include <linux/module.h> +#include <linux/kdb.h> +#include "internal.h" + +/* + * kdb_lsmod - This function implements the 'lsmod' command. Lists + * currently loaded kernel modules. + * Mostly taken from userland lsmod. + */ +int kdb_lsmod(int argc, const char **argv) +{ + struct module *mod; + + if (argc != 0) + return KDB_ARGCOUNT; + + kdb_printf("Module Size modstruct Used by\n"); + list_for_each_entry(mod, &modules, list) { + if (mod->state == MODULE_STATE_UNFORMED) + continue; + + kdb_printf("%-20s%8u", mod->name, mod->core_layout.size); +#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC + kdb_printf("/%8u", mod->data_layout.size); +#endif + kdb_printf(" 0x%px ", (void *)mod); +#ifdef CONFIG_MODULE_UNLOAD + kdb_printf("%4d ", module_refcount(mod)); +#endif + if (mod->state == MODULE_STATE_GOING) + kdb_printf(" (Unloading)"); + else if (mod->state == MODULE_STATE_COMING) + kdb_printf(" (Loading)"); + else + kdb_printf(" (Live)"); + kdb_printf(" 0x%px", mod->core_layout.base); +#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC + kdb_printf("/0x%px", mod->data_layout.base); +#endif + +#ifdef CONFIG_MODULE_UNLOAD + { + struct module_use *use; + + kdb_printf(" [ "); + list_for_each_entry(use, &mod->source_list, + source_list) + kdb_printf("%s ", use->target->name); + kdb_printf("]\n"); + } +#endif + } + + return 0; +} diff --git a/kernel/module/livepatch.c b/kernel/module/livepatch.c new file mode 100644 index 000000000000..486d4ff92719 --- /dev/null +++ b/kernel/module/livepatch.c @@ -0,0 +1,74 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Module livepatch support + * + * Copyright (C) 2016 Jessica Yu <jeyu@redhat.com> + */ + +#include <linux/module.h> +#include <linux/string.h> +#include <linux/slab.h> +#include "internal.h" + +/* + * Persist Elf information about a module. Copy the Elf header, + * section header table, section string table, and symtab section + * index from info to mod->klp_info. + */ +int copy_module_elf(struct module *mod, struct load_info *info) +{ + unsigned int size, symndx; + int ret; + + size = sizeof(*mod->klp_info); + mod->klp_info = kmalloc(size, GFP_KERNEL); + if (!mod->klp_info) + return -ENOMEM; + + /* Elf header */ + size = sizeof(mod->klp_info->hdr); + memcpy(&mod->klp_info->hdr, info->hdr, size); + + /* Elf section header table */ + size = sizeof(*info->sechdrs) * info->hdr->e_shnum; + mod->klp_info->sechdrs = kmemdup(info->sechdrs, size, GFP_KERNEL); + if (!mod->klp_info->sechdrs) { + ret = -ENOMEM; + goto free_info; + } + + /* Elf section name string table */ + size = info->sechdrs[info->hdr->e_shstrndx].sh_size; + mod->klp_info->secstrings = kmemdup(info->secstrings, size, GFP_KERNEL); + if (!mod->klp_info->secstrings) { + ret = -ENOMEM; + goto free_sechdrs; + } + + /* Elf symbol section index */ + symndx = info->index.sym; + mod->klp_info->symndx = symndx; + + /* + * For livepatch modules, core_kallsyms.symtab is a complete + * copy of the original symbol table. Adjust sh_addr to point + * to core_kallsyms.symtab since the copy of the symtab in module + * init memory is freed at the end of do_init_module(). + */ + mod->klp_info->sechdrs[symndx].sh_addr = (unsigned long)mod->core_kallsyms.symtab; + + return 0; + +free_sechdrs: + kfree(mod->klp_info->sechdrs); +free_info: + kfree(mod->klp_info); + return ret; +} + +void free_module_elf(struct module *mod) +{ + kfree(mod->klp_info->sechdrs); + kfree(mod->klp_info->secstrings); + kfree(mod->klp_info); +} diff --git a/kernel/module.c b/kernel/module/main.c index c9e2342da28e..fed58d30725d 100644 --- a/kernel/module.c +++ b/kernel/module/main.c @@ -14,16 +14,12 @@ #include <linux/init.h> #include <linux/kallsyms.h> #include <linux/buildid.h> -#include <linux/file.h> #include <linux/fs.h> -#include <linux/sysfs.h> #include <linux/kernel.h> #include <linux/kernel_read_file.h> #include <linux/slab.h> #include <linux/vmalloc.h> #include <linux/elf.h> -#include <linux/proc_fs.h> -#include <linux/security.h> #include <linux/seq_file.h> #include <linux/syscalls.h> #include <linux/fcntl.h> @@ -58,237 +54,70 @@ #include <linux/dynamic_debug.h> #include <linux/audit.h> #include <uapi/linux/module.h> -#include "module-internal.h" +#include "internal.h" #define CREATE_TRACE_POINTS #include <trace/events/module.h> -#ifndef ARCH_SHF_SMALL -#define ARCH_SHF_SMALL 0 -#endif - -/* - * Modules' sections will be aligned on page boundaries - * to ensure complete separation of code and data, but - * only when CONFIG_ARCH_HAS_STRICT_MODULE_RWX=y - */ -#ifdef CONFIG_ARCH_HAS_STRICT_MODULE_RWX -# define debug_align(X) ALIGN(X, PAGE_SIZE) -#else -# define debug_align(X) (X) -#endif - -/* If this is set, the section belongs in the init part of the module */ -#define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1)) - /* * Mutex protects: * 1) List of modules (also safely readable with preempt_disable), * 2) module_use links, - * 3) module_addr_min/module_addr_max. + * 3) mod_tree.addr_min/mod_tree.addr_max. * (delete and add uses RCU list operations). */ -static DEFINE_MUTEX(module_mutex); -static LIST_HEAD(modules); +DEFINE_MUTEX(module_mutex); +LIST_HEAD(modules); /* Work queue for freeing init sections in success case */ static void do_free_init(struct work_struct *w); static DECLARE_WORK(init_free_wq, do_free_init); static LLIST_HEAD(init_free_list); -#ifdef CONFIG_MODULES_TREE_LOOKUP - -/* - * Use a latched RB-tree for __module_address(); this allows us to use - * RCU-sched lookups of the address from any context. - * - * This is conditional on PERF_EVENTS || TRACING because those can really hit - * __module_address() hard by doing a lot of stack unwinding; potentially from - * NMI context. - */ - -static __always_inline unsigned long __mod_tree_val(struct latch_tree_node *n) -{ - struct module_layout *layout = container_of(n, struct module_layout, mtn.node); - - return (unsigned long)layout->base; -} - -static __always_inline unsigned long __mod_tree_size(struct latch_tree_node *n) -{ - struct module_layout *layout = container_of(n, struct module_layout, mtn.node); - - return (unsigned long)layout->size; -} - -static __always_inline bool -mod_tree_less(struct latch_tree_node *a, struct latch_tree_node *b) -{ - return __mod_tree_val(a) < __mod_tree_val(b); -} - -static __always_inline int -mod_tree_comp(void *key, struct latch_tree_node *n) -{ - unsigned long val = (unsigned long)key; - unsigned long start, end; - - start = __mod_tree_val(n); - if (val < start) - return -1; - - end = start + __mod_tree_size(n); - if (val >= end) - return 1; - - return 0; -} - -static const struct latch_tree_ops mod_tree_ops = { - .less = mod_tree_less, - .comp = mod_tree_comp, +struct mod_tree_root mod_tree __cacheline_aligned = { + .addr_min = -1UL, }; -static struct mod_tree_root { - struct latch_tree_root root; - unsigned long addr_min; - unsigned long addr_max; -} mod_tree __cacheline_aligned = { +#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC +struct mod_tree_root mod_data_tree __cacheline_aligned = { .addr_min = -1UL, }; +#endif #define module_addr_min mod_tree.addr_min #define module_addr_max mod_tree.addr_max -static noinline void __mod_tree_insert(struct mod_tree_node *node) -{ - latch_tree_insert(&node->node, &mod_tree.root, &mod_tree_ops); -} - -static void __mod_tree_remove(struct mod_tree_node *node) -{ - latch_tree_erase(&node->node, &mod_tree.root, &mod_tree_ops); -} - -/* - * These modifications: insert, remove_init and remove; are serialized by the - * module_mutex. - */ -static void mod_tree_insert(struct module *mod) -{ - mod->core_layout.mtn.mod = mod; - mod->init_layout.mtn.mod = mod; - - __mod_tree_insert(&mod->core_layout.mtn); - if (mod->init_layout.size) - __mod_tree_insert(&mod->init_layout.mtn); -} - -static void mod_tree_remove_init(struct module *mod) -{ - if (mod->init_layout.size) - __mod_tree_remove(&mod->init_layout.mtn); -} - -static void mod_tree_remove(struct module *mod) -{ - __mod_tree_remove(&mod->core_layout.mtn); - mod_tree_remove_init(mod); -} - -static struct module *mod_find(unsigned long addr) -{ - struct latch_tree_node *ltn; - - ltn = latch_tree_find((void *)addr, &mod_tree.root, &mod_tree_ops); - if (!ltn) - return NULL; - - return container_of(ltn, struct mod_tree_node, node)->mod; -} - -#else /* MODULES_TREE_LOOKUP */ - -static unsigned long module_addr_min = -1UL, module_addr_max = 0; - -static void mod_tree_insert(struct module *mod) { } -static void mod_tree_remove_init(struct module *mod) { } -static void mod_tree_remove(struct module *mod) { } - -static struct module *mod_find(unsigned long addr) -{ - struct module *mod; - - list_for_each_entry_rcu(mod, &modules, list, - lockdep_is_held(&module_mutex)) { - if (within_module(addr, mod)) - return mod; - } - - return NULL; -} - -#endif /* MODULES_TREE_LOOKUP */ +struct symsearch { + const struct kernel_symbol *start, *stop; + const s32 *crcs; + enum mod_license license; +}; /* * Bounds of module text, for speeding up __module_address. * Protected by module_mutex. */ -static void __mod_update_bounds(void *base, unsigned int size) +static void __mod_update_bounds(void *base, unsigned int size, struct mod_tree_root *tree) { unsigned long min = (unsigned long)base; unsigned long max = min + size; - if (min < module_addr_min) - module_addr_min = min; - if (max > module_addr_max) - module_addr_max = max; + if (min < tree->addr_min) + tree->addr_min = min; + if (max > tree->addr_max) + tree->addr_max = max; } static void mod_update_bounds(struct module *mod) { - __mod_update_bounds(mod->core_layout.base, mod->core_layout.size); + __mod_update_bounds(mod->core_layout.base, mod->core_layout.size, &mod_tree); if (mod->init_layout.size) - __mod_update_bounds(mod->init_layout.base, mod->init_layout.size); -} - -#ifdef CONFIG_KGDB_KDB -struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */ -#endif /* CONFIG_KGDB_KDB */ - -static void module_assert_mutex_or_preempt(void) -{ -#ifdef CONFIG_LOCKDEP - if (unlikely(!debug_locks)) - return; - - WARN_ON_ONCE(!rcu_read_lock_sched_held() && - !lockdep_is_held(&module_mutex)); + __mod_update_bounds(mod->init_layout.base, mod->init_layout.size, &mod_tree); +#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC + __mod_update_bounds(mod->data_layout.base, mod->data_layout.size, &mod_data_tree); #endif } -#ifdef CONFIG_MODULE_SIG -static bool sig_enforce = IS_ENABLED(CONFIG_MODULE_SIG_FORCE); -module_param(sig_enforce, bool_enable_only, 0644); - -void set_module_sig_enforced(void) -{ - sig_enforce = true; -} -#else -#define sig_enforce false -#endif - -/* - * Export sig_enforce kernel cmdline parameter to allow other subsystems rely - * on that instead of directly to CONFIG_MODULE_SIG_FORCE config. - */ -bool is_module_sig_enforced(void) -{ - return sig_enforce; -} -EXPORT_SYMBOL(is_module_sig_enforced); - /* Block module loading/unloading? */ int modules_disabled = 0; core_param(nomodule, modules_disabled, bint, 0); @@ -408,66 +237,12 @@ static __maybe_unused void *any_section_objs(const struct load_info *info, return (void *)info->sechdrs[sec].sh_addr; } -/* Provided by the linker */ -extern const struct kernel_symbol __start___ksymtab[]; -extern const struct kernel_symbol __stop___ksymtab[]; -extern const struct kernel_symbol __start___ksymtab_gpl[]; -extern const struct kernel_symbol __stop___ksymtab_gpl[]; -extern const s32 __start___kcrctab[]; -extern const s32 __start___kcrctab_gpl[]; - #ifndef CONFIG_MODVERSIONS #define symversion(base, idx) NULL #else #define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL) #endif -struct symsearch { - const struct kernel_symbol *start, *stop; - const s32 *crcs; - enum mod_license { - NOT_GPL_ONLY, - GPL_ONLY, - } license; -}; - -struct find_symbol_arg { - /* Input */ - const char *name; - bool gplok; - bool warn; - - /* Output */ - struct module *owner; - const s32 *crc; - const struct kernel_symbol *sym; - enum mod_license license; -}; - -static bool check_exported_symbol(const struct symsearch *syms, - struct module *owner, - unsigned int symnum, void *data) -{ - struct find_symbol_arg *fsa = data; - - if (!fsa->gplok && syms->license == GPL_ONLY) - return false; - fsa->owner = owner; - fsa->crc = symversion(syms->crcs, symnum); - fsa->sym = &syms->start[symnum]; - fsa->license = syms->license; - return true; -} - -static unsigned long kernel_symbol_value(const struct kernel_symbol *sym) -{ -#ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS - return (unsigned long)offset_to_ptr(&sym->value_offset); -#else - return sym->value; -#endif -} - static const char *kernel_symbol_name(const struct kernel_symbol *sym) { #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS @@ -488,33 +263,38 @@ static const char *kernel_symbol_namespace(const struct kernel_symbol *sym) #endif } -static int cmp_name(const void *name, const void *sym) +int cmp_name(const void *name, const void *sym) { return strcmp(name, kernel_symbol_name(sym)); } static bool find_exported_symbol_in_section(const struct symsearch *syms, struct module *owner, - void *data) + struct find_symbol_arg *fsa) { - struct find_symbol_arg *fsa = data; struct kernel_symbol *sym; + if (!fsa->gplok && syms->license == GPL_ONLY) + return false; + sym = bsearch(fsa->name, syms->start, syms->stop - syms->start, sizeof(struct kernel_symbol), cmp_name); + if (!sym) + return false; - if (sym != NULL && check_exported_symbol(syms, owner, - sym - syms->start, data)) - return true; + fsa->owner = owner; + fsa->crc = symversion(syms->crcs, sym - syms->start); + fsa->sym = sym; + fsa->license = syms->license; - return false; + return true; } /* * Find an exported symbol and return it, along with, (optional) crc and * (optional) module which owns it. Needs preempt disabled or module_mutex. */ -static bool find_symbol(struct find_symbol_arg *fsa) +bool find_symbol(struct find_symbol_arg *fsa) { static const struct symsearch arr[] = { { __start___ksymtab, __stop___ksymtab, __start___kcrctab, @@ -558,8 +338,8 @@ static bool find_symbol(struct find_symbol_arg *fsa) * Search for module by name: must hold module_mutex (or preempt disabled * for read-only access). */ -static struct module *find_module_all(const char *name, size_t len, - bool even_unformed) +struct module *find_module_all(const char *name, size_t len, + bool even_unformed) { struct module *mod; @@ -985,31 +765,6 @@ out: return ret; } -static inline void print_unload_info(struct seq_file *m, struct module *mod) -{ - struct module_use *use; - int printed_something = 0; - - seq_printf(m, " %i ", module_refcount(mod)); - - /* - * Always include a trailing , so userspace can differentiate - * between this and the old multi-field proc format. - */ - list_for_each_entry(use, &mod->source_list, source_list) { - printed_something = 1; - seq_printf(m, "%s,", use->source->name); - } - - if (mod->init != NULL && mod->exit == NULL) { - printed_something = 1; - seq_puts(m, "[permanent],"); - } - - if (!printed_something) - seq_puts(m, "-"); -} - void __symbol_put(const char *symbol) { struct find_symbol_arg fsa = { @@ -1099,12 +854,6 @@ void module_put(struct module *module) EXPORT_SYMBOL(module_put); #else /* !CONFIG_MODULE_UNLOAD */ -static inline void print_unload_info(struct seq_file *m, struct module *mod) -{ - /* We don't know the usage count, or what modules are using. */ - seq_puts(m, " - -"); -} - static inline void module_unload_free(struct module *mod) { } @@ -1120,13 +869,13 @@ static inline int module_unload_init(struct module *mod) } #endif /* CONFIG_MODULE_UNLOAD */ -static size_t module_flags_taint(struct module *mod, char *buf) +size_t module_flags_taint(unsigned long taints, char *buf) { size_t l = 0; int i; for (i = 0; i < TAINT_FLAGS_COUNT; i++) { - if (taint_flags[i].module && test_bit(i, &mod->taints)) + if (taint_flags[i].module && test_bit(i, &taints)) buf[l++] = taint_flags[i].c_true; } @@ -1179,6 +928,17 @@ static ssize_t show_coresize(struct module_attribute *mattr, static struct module_attribute modinfo_coresize = __ATTR(coresize, 0444, show_coresize, NULL); +#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC +static ssize_t show_datasize(struct module_attribute *mattr, + struct module_kobject *mk, char *buffer) +{ + return sprintf(buffer, "%u\n", mk->mod->data_layout.size); +} + +static struct module_attribute modinfo_datasize = + __ATTR(datasize, 0444, show_datasize, NULL); +#endif + static ssize_t show_initsize(struct module_attribute *mattr, struct module_kobject *mk, char *buffer) { @@ -1193,7 +953,7 @@ static ssize_t show_taint(struct module_attribute *mattr, { size_t l; - l = module_flags_taint(mk->mod, buffer); + l = module_flags_taint(mk->mod->taints, buffer); buffer[l++] = '\n'; return l; } @@ -1201,12 +961,15 @@ static ssize_t show_taint(struct module_attribute *mattr, static struct module_attribute modinfo_taint = __ATTR(taint, 0444, show_taint, NULL); -static struct module_attribute *modinfo_attrs[] = { +struct module_attribute *modinfo_attrs[] = { &module_uevent, &modinfo_version, &modinfo_srcversion, &modinfo_initstate, &modinfo_coresize, +#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC + &modinfo_datasize, +#endif &modinfo_initsize, &modinfo_taint, #ifdef CONFIG_MODULE_UNLOAD @@ -1215,9 +978,11 @@ static struct module_attribute *modinfo_attrs[] = { NULL, }; +size_t modinfo_attrs_count = ARRAY_SIZE(modinfo_attrs); + static const char vermagic[] = VERMAGIC_STRING; -static int try_to_force_load(struct module *mod, const char *reason) +int try_to_force_load(struct module *mod, const char *reason) { #ifdef CONFIG_MODULE_FORCE_LOAD if (!test_taint(TAINT_FORCED_MODULE)) @@ -1229,107 +994,6 @@ static int try_to_force_load(struct module *mod, const char *reason) #endif } -#ifdef CONFIG_MODVERSIONS - -static int check_version(const struct load_info *info, - const char *symname, - struct module *mod, - const s32 *crc) -{ - Elf_Shdr *sechdrs = info->sechdrs; - unsigned int versindex = info->index.vers; - unsigned int i, num_versions; - struct modversion_info *versions; - - /* Exporting module didn't supply crcs? OK, we're already tainted. */ - if (!crc) - return 1; - - /* No versions at all? modprobe --force does this. */ - if (versindex == 0) - return try_to_force_load(mod, symname) == 0; - - versions = (void *) sechdrs[versindex].sh_addr; - num_versions = sechdrs[versindex].sh_size - / sizeof(struct modversion_info); - - for (i = 0; i < num_versions; i++) { - u32 crcval; - - if (strcmp(versions[i].name, symname) != 0) - continue; - - crcval = *crc; - if (versions[i].crc == crcval) - return 1; - pr_debug("Found checksum %X vs module %lX\n", - crcval, versions[i].crc); - goto bad_version; - } - - /* Broken toolchain. Warn once, then let it go.. */ - pr_warn_once("%s: no symbol version for %s\n", info->name, symname); - return 1; - -bad_version: - pr_warn("%s: disagrees about version of symbol %s\n", - info->name, symname); - return 0; -} - -static inline int check_modstruct_version(const struct load_info *info, - struct module *mod) -{ - struct find_symbol_arg fsa = { - .name = "module_layout", - .gplok = true, - }; - - /* - * Since this should be found in kernel (which can't be removed), no - * locking is necessary -- use preempt_disable() to placate lockdep. - */ - preempt_disable(); - if (!find_symbol(&fsa)) { - preempt_enable(); - BUG(); - } - preempt_enable(); - return check_version(info, "module_layout", mod, fsa.crc); -} - -/* First part is kernel version, which we ignore if module has crcs. */ -static inline int same_magic(const char *amagic, const char *bmagic, - bool has_crcs) -{ - if (has_crcs) { - amagic += strcspn(amagic, " "); - bmagic += strcspn(bmagic, " "); - } - return strcmp(amagic, bmagic) == 0; -} -#else -static inline int check_version(const struct load_info *info, - const char *symname, - struct module *mod, - const s32 *crc) -{ - return 1; -} - -static inline int check_modstruct_version(const struct load_info *info, - struct module *mod) -{ - return 1; -} - -static inline int same_magic(const char *amagic, const char *bmagic, - bool has_crcs) -{ - return strcmp(amagic, bmagic) == 0; -} -#endif /* CONFIG_MODVERSIONS */ - static char *get_modinfo(const struct load_info *info, const char *tag); static char *get_next_modinfo(const struct load_info *info, const char *tag, char *prev); @@ -1364,20 +1028,20 @@ static int verify_namespace_is_imported(const struct load_info *info, return 0; } -static bool inherit_taint(struct module *mod, struct module *owner) +static bool inherit_taint(struct module *mod, struct module *owner, const char *name) { if (!owner || !test_bit(TAINT_PROPRIETARY_MODULE, &owner->taints)) return true; if (mod->using_gplonly_symbols) { - pr_err("%s: module using GPL-only symbols uses symbols from proprietary module %s.\n", - mod->name, owner->name); + pr_err("%s: module using GPL-only symbols uses symbols %s from proprietary module %s.\n", + mod->name, name, owner->name); return false; } if (!test_bit(TAINT_PROPRIETARY_MODULE, &mod->taints)) { - pr_warn("%s: module uses symbols from proprietary module %s, inheriting taint.\n", - mod->name, owner->name); + pr_warn("%s: module uses symbols %s from proprietary module %s, inheriting taint.\n", + mod->name, name, owner->name); set_bit(TAINT_PROPRIETARY_MODULE, &mod->taints); } return true; @@ -1409,7 +1073,7 @@ static const struct kernel_symbol *resolve_symbol(struct module *mod, if (fsa.license == GPL_ONLY) mod->using_gplonly_symbols = true; - if (!inherit_taint(mod, fsa.owner)) { + if (!inherit_taint(mod, fsa.owner, name)) { fsa.sym = NULL; goto getname; } @@ -1457,674 +1121,6 @@ resolve_symbol_wait(struct module *mod, return ksym; } -#ifdef CONFIG_KALLSYMS -static inline bool sect_empty(const Elf_Shdr *sect) -{ - return !(sect->sh_flags & SHF_ALLOC) || sect->sh_size == 0; -} -#endif - -/* - * /sys/module/foo/sections stuff - * J. Corbet <corbet@lwn.net> - */ -#ifdef CONFIG_SYSFS - -#ifdef CONFIG_KALLSYMS -struct module_sect_attr { - struct bin_attribute battr; - unsigned long address; -}; - -struct module_sect_attrs { - struct attribute_group grp; - unsigned int nsections; - struct module_sect_attr attrs[]; -}; - -#define MODULE_SECT_READ_SIZE (3 /* "0x", "\n" */ + (BITS_PER_LONG / 4)) -static ssize_t module_sect_read(struct file *file, struct kobject *kobj, - struct bin_attribute *battr, - char *buf, loff_t pos, size_t count) -{ - struct module_sect_attr *sattr = - container_of(battr, struct module_sect_attr, battr); - char bounce[MODULE_SECT_READ_SIZE + 1]; - size_t wrote; - - if (pos != 0) - return -EINVAL; - - /* - * Since we're a binary read handler, we must account for the - * trailing NUL byte that sprintf will write: if "buf" is - * too small to hold the NUL, or the NUL is exactly the last - * byte, the read will look like it got truncated by one byte. - * Since there is no way to ask sprintf nicely to not write - * the NUL, we have to use a bounce buffer. - */ - wrote = scnprintf(bounce, sizeof(bounce), "0x%px\n", - kallsyms_show_value(file->f_cred) - ? (void *)sattr->address : NULL); - count = min(count, wrote); - memcpy(buf, bounce, count); - - return count; -} - -static void free_sect_attrs(struct module_sect_attrs *sect_attrs) -{ - unsigned int section; - - for (section = 0; section < sect_attrs->nsections; section++) - kfree(sect_attrs->attrs[section].battr.attr.name); - kfree(sect_attrs); -} - -static void add_sect_attrs(struct module *mod, const struct load_info *info) -{ - unsigned int nloaded = 0, i, size[2]; - struct module_sect_attrs *sect_attrs; - struct module_sect_attr *sattr; - struct bin_attribute **gattr; - - /* Count loaded sections and allocate structures */ - for (i = 0; i < info->hdr->e_shnum; i++) - if (!sect_empty(&info->sechdrs[i])) - nloaded++; - size[0] = ALIGN(struct_size(sect_attrs, attrs, nloaded), - sizeof(sect_attrs->grp.bin_attrs[0])); - size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.bin_attrs[0]); - sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL); - if (sect_attrs == NULL) - return; - - /* Setup section attributes. */ - sect_attrs->grp.name = "sections"; - sect_attrs->grp.bin_attrs = (void *)sect_attrs + size[0]; - - sect_attrs->nsections = 0; - sattr = §_attrs->attrs[0]; - gattr = §_attrs->grp.bin_attrs[0]; - for (i = 0; i < info->hdr->e_shnum; i++) { - Elf_Shdr *sec = &info->sechdrs[i]; - if (sect_empty(sec)) - continue; - sysfs_bin_attr_init(&sattr->battr); - sattr->address = sec->sh_addr; - sattr->battr.attr.name = - kstrdup(info->secstrings + sec->sh_name, GFP_KERNEL); - if (sattr->battr.attr.name == NULL) - goto out; - sect_attrs->nsections++; - sattr->battr.read = module_sect_read; - sattr->battr.size = MODULE_SECT_READ_SIZE; - sattr->battr.attr.mode = 0400; - *(gattr++) = &(sattr++)->battr; - } - *gattr = NULL; - - if (sysfs_create_group(&mod->mkobj.kobj, §_attrs->grp)) - goto out; - - mod->sect_attrs = sect_attrs; - return; - out: - free_sect_attrs(sect_attrs); -} - -static void remove_sect_attrs(struct module *mod) -{ - if (mod->sect_attrs) { - sysfs_remove_group(&mod->mkobj.kobj, - &mod->sect_attrs->grp); - /* - * We are positive that no one is using any sect attrs - * at this point. Deallocate immediately. - */ - free_sect_attrs(mod->sect_attrs); - mod->sect_attrs = NULL; - } -} - -/* - * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections. - */ - -struct module_notes_attrs { - struct kobject *dir; - unsigned int notes; - struct bin_attribute attrs[]; -}; - -static ssize_t module_notes_read(struct file *filp, struct kobject *kobj, - struct bin_attribute *bin_attr, - char *buf, loff_t pos, size_t count) -{ - /* - * The caller checked the pos and count against our size. - */ - memcpy(buf, bin_attr->private + pos, count); - return count; -} - -static void free_notes_attrs(struct module_notes_attrs *notes_attrs, - unsigned int i) -{ - if (notes_attrs->dir) { - while (i-- > 0) - sysfs_remove_bin_file(notes_attrs->dir, - ¬es_attrs->attrs[i]); - kobject_put(notes_attrs->dir); - } - kfree(notes_attrs); -} - -static void add_notes_attrs(struct module *mod, const struct load_info *info) -{ - unsigned int notes, loaded, i; - struct module_notes_attrs *notes_attrs; - struct bin_attribute *nattr; - - /* failed to create section attributes, so can't create notes */ - if (!mod->sect_attrs) - return; - - /* Count notes sections and allocate structures. */ - notes = 0; - for (i = 0; i < info->hdr->e_shnum; i++) - if (!sect_empty(&info->sechdrs[i]) && - (info->sechdrs[i].sh_type == SHT_NOTE)) - ++notes; - - if (notes == 0) - return; - - notes_attrs = kzalloc(struct_size(notes_attrs, attrs, notes), - GFP_KERNEL); - if (notes_attrs == NULL) - return; - - notes_attrs->notes = notes; - nattr = ¬es_attrs->attrs[0]; - for (loaded = i = 0; i < info->hdr->e_shnum; ++i) { - if (sect_empty(&info->sechdrs[i])) - continue; - if (info->sechdrs[i].sh_type == SHT_NOTE) { - sysfs_bin_attr_init(nattr); - nattr->attr.name = mod->sect_attrs->attrs[loaded].battr.attr.name; - nattr->attr.mode = S_IRUGO; - nattr->size = info->sechdrs[i].sh_size; - nattr->private = (void *) info->sechdrs[i].sh_addr; - nattr->read = module_notes_read; - ++nattr; - } - ++loaded; - } - - notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj); - if (!notes_attrs->dir) - goto out; - - for (i = 0; i < notes; ++i) - if (sysfs_create_bin_file(notes_attrs->dir, - ¬es_attrs->attrs[i])) - goto out; - - mod->notes_attrs = notes_attrs; - return; - - out: - free_notes_attrs(notes_attrs, i); -} - -static void remove_notes_attrs(struct module *mod) -{ - if (mod->notes_attrs) - free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes); -} - -#else - -static inline void add_sect_attrs(struct module *mod, - const struct load_info *info) -{ -} - -static inline void remove_sect_attrs(struct module *mod) -{ -} - -static inline void add_notes_attrs(struct module *mod, - const struct load_info *info) -{ -} - -static inline void remove_notes_attrs(struct module *mod) -{ -} -#endif /* CONFIG_KALLSYMS */ - -static void del_usage_links(struct module *mod) -{ -#ifdef CONFIG_MODULE_UNLOAD - struct module_use *use; - - mutex_lock(&module_mutex); - list_for_each_entry(use, &mod->target_list, target_list) - sysfs_remove_link(use->target->holders_dir, mod->name); - mutex_unlock(&module_mutex); -#endif -} - -static int add_usage_links(struct module *mod) -{ - int ret = 0; -#ifdef CONFIG_MODULE_UNLOAD - struct module_use *use; - - mutex_lock(&module_mutex); - list_for_each_entry(use, &mod->target_list, target_list) { - ret = sysfs_create_link(use->target->holders_dir, - &mod->mkobj.kobj, mod->name); - if (ret) - break; - } - mutex_unlock(&module_mutex); - if (ret) - del_usage_links(mod); -#endif - return ret; -} - -static void module_remove_modinfo_attrs(struct module *mod, int end); - -static int module_add_modinfo_attrs(struct module *mod) -{ - struct module_attribute *attr; - struct module_attribute *temp_attr; - int error = 0; - int i; - - mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) * - (ARRAY_SIZE(modinfo_attrs) + 1)), - GFP_KERNEL); - if (!mod->modinfo_attrs) - return -ENOMEM; - - temp_attr = mod->modinfo_attrs; - for (i = 0; (attr = modinfo_attrs[i]); i++) { - if (!attr->test || attr->test(mod)) { - memcpy(temp_attr, attr, sizeof(*temp_attr)); - sysfs_attr_init(&temp_attr->attr); - error = sysfs_create_file(&mod->mkobj.kobj, - &temp_attr->attr); - if (error) - goto error_out; - ++temp_attr; - } - } - - return 0; - -error_out: - if (i > 0) - module_remove_modinfo_attrs(mod, --i); - else - kfree(mod->modinfo_attrs); - return error; -} - -static void module_remove_modinfo_attrs(struct module *mod, int end) -{ - struct module_attribute *attr; - int i; - - for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) { - if (end >= 0 && i > end) - break; - /* pick a field to test for end of list */ - if (!attr->attr.name) - break; - sysfs_remove_file(&mod->mkobj.kobj, &attr->attr); - if (attr->free) - attr->free(mod); - } - kfree(mod->modinfo_attrs); -} - -static void mod_kobject_put(struct module *mod) -{ - DECLARE_COMPLETION_ONSTACK(c); - mod->mkobj.kobj_completion = &c; - kobject_put(&mod->mkobj.kobj); - wait_for_completion(&c); -} - -static int mod_sysfs_init(struct module *mod) -{ - int err; - struct kobject *kobj; - - if (!module_sysfs_initialized) { - pr_err("%s: module sysfs not initialized\n", mod->name); - err = -EINVAL; - goto out; - } - - kobj = kset_find_obj(module_kset, mod->name); - if (kobj) { - pr_err("%s: module is already loaded\n", mod->name); - kobject_put(kobj); - err = -EINVAL; - goto out; - } - - mod->mkobj.mod = mod; - - memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj)); - mod->mkobj.kobj.kset = module_kset; - err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL, - "%s", mod->name); - if (err) - mod_kobject_put(mod); - -out: - return err; -} - -static int mod_sysfs_setup(struct module *mod, - const struct load_info *info, - struct kernel_param *kparam, - unsigned int num_params) -{ - int err; - - err = mod_sysfs_init(mod); - if (err) - goto out; - - mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj); - if (!mod->holders_dir) { - err = -ENOMEM; - goto out_unreg; - } - - err = module_param_sysfs_setup(mod, kparam, num_params); - if (err) - goto out_unreg_holders; - - err = module_add_modinfo_attrs(mod); - if (err) - goto out_unreg_param; - - err = add_usage_links(mod); - if (err) - goto out_unreg_modinfo_attrs; - - add_sect_attrs(mod, info); - add_notes_attrs(mod, info); - - return 0; - -out_unreg_modinfo_attrs: - module_remove_modinfo_attrs(mod, -1); -out_unreg_param: - module_param_sysfs_remove(mod); -out_unreg_holders: - kobject_put(mod->holders_dir); -out_unreg: - mod_kobject_put(mod); -out: - return err; -} - -static void mod_sysfs_fini(struct module *mod) -{ - remove_notes_attrs(mod); - remove_sect_attrs(mod); - mod_kobject_put(mod); -} - -static void init_param_lock(struct module *mod) -{ - mutex_init(&mod->param_lock); -} -#else /* !CONFIG_SYSFS */ - -static int mod_sysfs_setup(struct module *mod, - const struct load_info *info, - struct kernel_param *kparam, - unsigned int num_params) -{ - return 0; -} - -static void mod_sysfs_fini(struct module *mod) -{ -} - -static void module_remove_modinfo_attrs(struct module *mod, int end) -{ -} - -static void del_usage_links(struct module *mod) -{ -} - -static void init_param_lock(struct module *mod) -{ -} -#endif /* CONFIG_SYSFS */ - -static void mod_sysfs_teardown(struct module *mod) -{ - del_usage_links(mod); - module_remove_modinfo_attrs(mod, -1); - module_param_sysfs_remove(mod); - kobject_put(mod->mkobj.drivers_dir); - kobject_put(mod->holders_dir); - mod_sysfs_fini(mod); -} - -/* - * LKM RO/NX protection: protect module's text/ro-data - * from modification and any data from execution. - * - * General layout of module is: - * [text] [read-only-data] [ro-after-init] [writable data] - * text_size -----^ ^ ^ ^ - * ro_size ------------------------| | | - * ro_after_init_size -----------------------------| | - * size -----------------------------------------------------------| - * - * These values are always page-aligned (as is base) - */ - -/* - * Since some arches are moving towards PAGE_KERNEL module allocations instead - * of PAGE_KERNEL_EXEC, keep frob_text() and module_enable_x() outside of the - * CONFIG_STRICT_MODULE_RWX block below because they are needed regardless of - * whether we are strict. - */ -#ifdef CONFIG_ARCH_HAS_STRICT_MODULE_RWX -static void frob_text(const struct module_layout *layout, - int (*set_memory)(unsigned long start, int num_pages)) -{ - BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1)); - BUG_ON((unsigned long)layout->text_size & (PAGE_SIZE-1)); - set_memory((unsigned long)layout->base, - layout->text_size >> PAGE_SHIFT); -} - -static void module_enable_x(const struct module *mod) -{ - frob_text(&mod->core_layout, set_memory_x); - frob_text(&mod->init_layout, set_memory_x); -} -#else /* !CONFIG_ARCH_HAS_STRICT_MODULE_RWX */ -static void module_enable_x(const struct module *mod) { } -#endif /* CONFIG_ARCH_HAS_STRICT_MODULE_RWX */ - -#ifdef CONFIG_STRICT_MODULE_RWX -static void frob_rodata(const struct module_layout *layout, - int (*set_memory)(unsigned long start, int num_pages)) -{ - BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1)); - BUG_ON((unsigned long)layout->text_size & (PAGE_SIZE-1)); - BUG_ON((unsigned long)layout->ro_size & (PAGE_SIZE-1)); - set_memory((unsigned long)layout->base + layout->text_size, - (layout->ro_size - layout->text_size) >> PAGE_SHIFT); -} - -static void frob_ro_after_init(const struct module_layout *layout, - int (*set_memory)(unsigned long start, int num_pages)) -{ - BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1)); - BUG_ON((unsigned long)layout->ro_size & (PAGE_SIZE-1)); - BUG_ON((unsigned long)layout->ro_after_init_size & (PAGE_SIZE-1)); - set_memory((unsigned long)layout->base + layout->ro_size, - (layout->ro_after_init_size - layout->ro_size) >> PAGE_SHIFT); -} - -static void frob_writable_data(const struct module_layout *layout, - int (*set_memory)(unsigned long start, int num_pages)) -{ - BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1)); - BUG_ON((unsigned long)layout->ro_after_init_size & (PAGE_SIZE-1)); - BUG_ON((unsigned long)layout->size & (PAGE_SIZE-1)); - set_memory((unsigned long)layout->base + layout->ro_after_init_size, - (layout->size - layout->ro_after_init_size) >> PAGE_SHIFT); -} - -static void module_enable_ro(const struct module *mod, bool after_init) -{ - if (!rodata_enabled) - return; - - set_vm_flush_reset_perms(mod->core_layout.base); - set_vm_flush_reset_perms(mod->init_layout.base); - frob_text(&mod->core_layout, set_memory_ro); - - frob_rodata(&mod->core_layout, set_memory_ro); - frob_text(&mod->init_layout, set_memory_ro); - frob_rodata(&mod->init_layout, set_memory_ro); - - if (after_init) - frob_ro_after_init(&mod->core_layout, set_memory_ro); -} - -static void module_enable_nx(const struct module *mod) -{ - frob_rodata(&mod->core_layout, set_memory_nx); - frob_ro_after_init(&mod->core_layout, set_memory_nx); - frob_writable_data(&mod->core_layout, set_memory_nx); - frob_rodata(&mod->init_layout, set_memory_nx); - frob_writable_data(&mod->init_layout, set_memory_nx); -} - -static int module_enforce_rwx_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs, - char *secstrings, struct module *mod) -{ - const unsigned long shf_wx = SHF_WRITE|SHF_EXECINSTR; - int i; - - for (i = 0; i < hdr->e_shnum; i++) { - if ((sechdrs[i].sh_flags & shf_wx) == shf_wx) { - pr_err("%s: section %s (index %d) has invalid WRITE|EXEC flags\n", - mod->name, secstrings + sechdrs[i].sh_name, i); - return -ENOEXEC; - } - } - - return 0; -} - -#else /* !CONFIG_STRICT_MODULE_RWX */ -static void module_enable_nx(const struct module *mod) { } -static void module_enable_ro(const struct module *mod, bool after_init) {} -static int module_enforce_rwx_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs, - char *secstrings, struct module *mod) -{ - return 0; -} -#endif /* CONFIG_STRICT_MODULE_RWX */ - -#ifdef CONFIG_LIVEPATCH -/* - * Persist Elf information about a module. Copy the Elf header, - * section header table, section string table, and symtab section - * index from info to mod->klp_info. - */ -static int copy_module_elf(struct module *mod, struct load_info *info) -{ - unsigned int size, symndx; - int ret; - - size = sizeof(*mod->klp_info); - mod->klp_info = kmalloc(size, GFP_KERNEL); - if (mod->klp_info == NULL) - return -ENOMEM; - - /* Elf header */ - size = sizeof(mod->klp_info->hdr); - memcpy(&mod->klp_info->hdr, info->hdr, size); - - /* Elf section header table */ - size = sizeof(*info->sechdrs) * info->hdr->e_shnum; - mod->klp_info->sechdrs = kmemdup(info->sechdrs, size, GFP_KERNEL); - if (mod->klp_info->sechdrs == NULL) { - ret = -ENOMEM; - goto free_info; - } - - /* Elf section name string table */ - size = info->sechdrs[info->hdr->e_shstrndx].sh_size; - mod->klp_info->secstrings = kmemdup(info->secstrings, size, GFP_KERNEL); - if (mod->klp_info->secstrings == NULL) { - ret = -ENOMEM; - goto free_sechdrs; - } - - /* Elf symbol section index */ - symndx = info->index.sym; - mod->klp_info->symndx = symndx; - - /* - * For livepatch modules, core_kallsyms.symtab is a complete - * copy of the original symbol table. Adjust sh_addr to point - * to core_kallsyms.symtab since the copy of the symtab in module - * init memory is freed at the end of do_init_module(). - */ - mod->klp_info->sechdrs[symndx].sh_addr = \ - (unsigned long) mod->core_kallsyms.symtab; - - return 0; - -free_sechdrs: - kfree(mod->klp_info->sechdrs); -free_info: - kfree(mod->klp_info); - return ret; -} - -static void free_module_elf(struct module *mod) -{ - kfree(mod->klp_info->sechdrs); - kfree(mod->klp_info->secstrings); - kfree(mod->klp_info); -} -#else /* !CONFIG_LIVEPATCH */ -static int copy_module_elf(struct module *mod, struct load_info *info) -{ - return 0; -} - -static void free_module_elf(struct module *mod) -{ -} -#endif /* CONFIG_LIVEPATCH */ - void __weak module_memfree(void *module_region) { /* @@ -2184,6 +1180,9 @@ static void free_module(struct module *mod) module_bug_cleanup(mod); /* Wait for RCU-sched synchronizing before releasing mod->list and buglist. */ synchronize_rcu(); + if (try_add_tainted_module(mod)) + pr_err("%s: adding tainted module to the unloaded tainted modules list failed.\n", + mod->name); mutex_unlock(&module_mutex); /* Clean up CFI for the module. */ @@ -2196,10 +1195,13 @@ static void free_module(struct module *mod) percpu_modfree(mod); /* Free lock-classes; relies on the preceding sync_rcu(). */ - lockdep_free_key_range(mod->core_layout.base, mod->core_layout.size); + lockdep_free_key_range(mod->data_layout.base, mod->data_layout.size); /* Finally, free the core (containing the module structure) */ module_memfree(mod->core_layout.base); +#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC + vfree(mod->data_layout.base); +#endif } void *__symbol_get(const char *symbol) @@ -2387,7 +1389,7 @@ unsigned int __weak arch_mod_section_prepend(struct module *mod, } /* Update size with this section: return offset. */ -static long get_offset(struct module *mod, unsigned int *size, +long module_get_offset(struct module *mod, unsigned int *size, Elf_Shdr *sechdr, unsigned int section) { long ret; @@ -2437,30 +1439,32 @@ static void layout_sections(struct module *mod, struct load_info *info) for (i = 0; i < info->hdr->e_shnum; ++i) { Elf_Shdr *s = &info->sechdrs[i]; const char *sname = info->secstrings + s->sh_name; + unsigned int *sizep; if ((s->sh_flags & masks[m][0]) != masks[m][0] || (s->sh_flags & masks[m][1]) || s->sh_entsize != ~0UL || module_init_layout_section(sname)) continue; - s->sh_entsize = get_offset(mod, &mod->core_layout.size, s, i); + sizep = m ? &mod->data_layout.size : &mod->core_layout.size; + s->sh_entsize = module_get_offset(mod, sizep, s, i); pr_debug("\t%s\n", sname); } switch (m) { case 0: /* executable */ - mod->core_layout.size = debug_align(mod->core_layout.size); + mod->core_layout.size = strict_align(mod->core_layout.size); mod->core_layout.text_size = mod->core_layout.size; break; case 1: /* RO: text and ro-data */ - mod->core_layout.size = debug_align(mod->core_layout.size); - mod->core_layout.ro_size = mod->core_layout.size; + mod->data_layout.size = strict_align(mod->data_layout.size); + mod->data_layout.ro_size = mod->data_layout.size; break; case 2: /* RO after init */ - mod->core_layout.size = debug_align(mod->core_layout.size); - mod->core_layout.ro_after_init_size = mod->core_layout.size; + mod->data_layout.size = strict_align(mod->data_layout.size); + mod->data_layout.ro_after_init_size = mod->data_layout.size; break; case 4: /* whole core */ - mod->core_layout.size = debug_align(mod->core_layout.size); + mod->data_layout.size = strict_align(mod->data_layout.size); break; } } @@ -2476,17 +1480,17 @@ static void layout_sections(struct module *mod, struct load_info *info) || s->sh_entsize != ~0UL || !module_init_layout_section(sname)) continue; - s->sh_entsize = (get_offset(mod, &mod->init_layout.size, s, i) + s->sh_entsize = (module_get_offset(mod, &mod->init_layout.size, s, i) | INIT_OFFSET_MASK); pr_debug("\t%s\n", sname); } switch (m) { case 0: /* executable */ - mod->init_layout.size = debug_align(mod->init_layout.size); + mod->init_layout.size = strict_align(mod->init_layout.size); mod->init_layout.text_size = mod->init_layout.size; break; case 1: /* RO: text and ro-data */ - mod->init_layout.size = debug_align(mod->init_layout.size); + mod->init_layout.size = strict_align(mod->init_layout.size); mod->init_layout.ro_size = mod->init_layout.size; break; case 2: @@ -2497,7 +1501,7 @@ static void layout_sections(struct module *mod, struct load_info *info) mod->init_layout.ro_after_init_size = mod->init_layout.ro_size; break; case 4: /* whole init */ - mod->init_layout.size = debug_align(mod->init_layout.size); + mod->init_layout.size = strict_align(mod->init_layout.size); break; } } @@ -2589,228 +1593,6 @@ static void free_modinfo(struct module *mod) } } -#ifdef CONFIG_KALLSYMS - -/* Lookup exported symbol in given range of kernel_symbols */ -static const struct kernel_symbol *lookup_exported_symbol(const char *name, - const struct kernel_symbol *start, - const struct kernel_symbol *stop) -{ - return bsearch(name, start, stop - start, - sizeof(struct kernel_symbol), cmp_name); -} - -static int is_exported(const char *name, unsigned long value, - const struct module *mod) -{ - const struct kernel_symbol *ks; - if (!mod) - ks = lookup_exported_symbol(name, __start___ksymtab, __stop___ksymtab); - else - ks = lookup_exported_symbol(name, mod->syms, mod->syms + mod->num_syms); - - return ks != NULL && kernel_symbol_value(ks) == value; -} - -/* As per nm */ -static char elf_type(const Elf_Sym *sym, const struct load_info *info) -{ - const Elf_Shdr *sechdrs = info->sechdrs; - - if (ELF_ST_BIND(sym->st_info) == STB_WEAK) { - if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT) - return 'v'; - else - return 'w'; - } - if (sym->st_shndx == SHN_UNDEF) - return 'U'; - if (sym->st_shndx == SHN_ABS || sym->st_shndx == info->index.pcpu) - return 'a'; - if (sym->st_shndx >= SHN_LORESERVE) - return '?'; - if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR) - return 't'; - if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC - && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) { - if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE)) - return 'r'; - else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL) - return 'g'; - else - return 'd'; - } - if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) { - if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL) - return 's'; - else - return 'b'; - } - if (strstarts(info->secstrings + sechdrs[sym->st_shndx].sh_name, - ".debug")) { - return 'n'; - } - return '?'; -} - -static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs, - unsigned int shnum, unsigned int pcpundx) -{ - const Elf_Shdr *sec; - - if (src->st_shndx == SHN_UNDEF - || src->st_shndx >= shnum - || !src->st_name) - return false; - -#ifdef CONFIG_KALLSYMS_ALL - if (src->st_shndx == pcpundx) - return true; -#endif - - sec = sechdrs + src->st_shndx; - if (!(sec->sh_flags & SHF_ALLOC) -#ifndef CONFIG_KALLSYMS_ALL - || !(sec->sh_flags & SHF_EXECINSTR) -#endif - || (sec->sh_entsize & INIT_OFFSET_MASK)) - return false; - - return true; -} - -/* - * We only allocate and copy the strings needed by the parts of symtab - * we keep. This is simple, but has the effect of making multiple - * copies of duplicates. We could be more sophisticated, see - * linux-kernel thread starting with - * <73defb5e4bca04a6431392cc341112b1@localhost>. - */ -static void layout_symtab(struct module *mod, struct load_info *info) -{ - Elf_Shdr *symsect = info->sechdrs + info->index.sym; - Elf_Shdr *strsect = info->sechdrs + info->index.str; - const Elf_Sym *src; - unsigned int i, nsrc, ndst, strtab_size = 0; - - /* Put symbol section at end of init part of module. */ - symsect->sh_flags |= SHF_ALLOC; - symsect->sh_entsize = get_offset(mod, &mod->init_layout.size, symsect, - info->index.sym) | INIT_OFFSET_MASK; - pr_debug("\t%s\n", info->secstrings + symsect->sh_name); - - src = (void *)info->hdr + symsect->sh_offset; - nsrc = symsect->sh_size / sizeof(*src); - - /* Compute total space required for the core symbols' strtab. */ - for (ndst = i = 0; i < nsrc; i++) { - if (i == 0 || is_livepatch_module(mod) || - is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum, - info->index.pcpu)) { - strtab_size += strlen(&info->strtab[src[i].st_name])+1; - ndst++; - } - } - - /* Append room for core symbols at end of core part. */ - info->symoffs = ALIGN(mod->core_layout.size, symsect->sh_addralign ?: 1); - info->stroffs = mod->core_layout.size = info->symoffs + ndst * sizeof(Elf_Sym); - mod->core_layout.size += strtab_size; - info->core_typeoffs = mod->core_layout.size; - mod->core_layout.size += ndst * sizeof(char); - mod->core_layout.size = debug_align(mod->core_layout.size); - - /* Put string table section at end of init part of module. */ - strsect->sh_flags |= SHF_ALLOC; - strsect->sh_entsize = get_offset(mod, &mod->init_layout.size, strsect, - info->index.str) | INIT_OFFSET_MASK; - pr_debug("\t%s\n", info->secstrings + strsect->sh_name); - - /* We'll tack temporary mod_kallsyms on the end. */ - mod->init_layout.size = ALIGN(mod->init_layout.size, - __alignof__(struct mod_kallsyms)); - info->mod_kallsyms_init_off = mod->init_layout.size; - mod->init_layout.size += sizeof(struct mod_kallsyms); - info->init_typeoffs = mod->init_layout.size; - mod->init_layout.size += nsrc * sizeof(char); - mod->init_layout.size = debug_align(mod->init_layout.size); -} - -/* - * We use the full symtab and strtab which layout_symtab arranged to - * be appended to the init section. Later we switch to the cut-down - * core-only ones. - */ -static void add_kallsyms(struct module *mod, const struct load_info *info) -{ - unsigned int i, ndst; - const Elf_Sym *src; - Elf_Sym *dst; - char *s; - Elf_Shdr *symsec = &info->sechdrs[info->index.sym]; - - /* Set up to point into init section. */ - mod->kallsyms = mod->init_layout.base + info->mod_kallsyms_init_off; - - mod->kallsyms->symtab = (void *)symsec->sh_addr; - mod->kallsyms->num_symtab = symsec->sh_size / sizeof(Elf_Sym); - /* Make sure we get permanent strtab: don't use info->strtab. */ - mod->kallsyms->strtab = (void *)info->sechdrs[info->index.str].sh_addr; - mod->kallsyms->typetab = mod->init_layout.base + info->init_typeoffs; - - /* - * Now populate the cut down core kallsyms for after init - * and set types up while we still have access to sections. - */ - mod->core_kallsyms.symtab = dst = mod->core_layout.base + info->symoffs; - mod->core_kallsyms.strtab = s = mod->core_layout.base + info->stroffs; - mod->core_kallsyms.typetab = mod->core_layout.base + info->core_typeoffs; - src = mod->kallsyms->symtab; - for (ndst = i = 0; i < mod->kallsyms->num_symtab; i++) { - mod->kallsyms->typetab[i] = elf_type(src + i, info); - if (i == 0 || is_livepatch_module(mod) || - is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum, - info->index.pcpu)) { - mod->core_kallsyms.typetab[ndst] = - mod->kallsyms->typetab[i]; - dst[ndst] = src[i]; - dst[ndst++].st_name = s - mod->core_kallsyms.strtab; - s += strlcpy(s, &mod->kallsyms->strtab[src[i].st_name], - KSYM_NAME_LEN) + 1; - } - } - mod->core_kallsyms.num_symtab = ndst; -} -#else -static inline void layout_symtab(struct module *mod, struct load_info *info) -{ -} - -static void add_kallsyms(struct module *mod, const struct load_info *info) -{ -} -#endif /* CONFIG_KALLSYMS */ - -#if IS_ENABLED(CONFIG_KALLSYMS) && IS_ENABLED(CONFIG_STACKTRACE_BUILD_ID) -static void init_build_id(struct module *mod, const struct load_info *info) -{ - const Elf_Shdr *sechdr; - unsigned int i; - - for (i = 0; i < info->hdr->e_shnum; i++) { - sechdr = &info->sechdrs[i]; - if (!sect_empty(sechdr) && sechdr->sh_type == SHT_NOTE && - !build_id_parse_buf((void *)sechdr->sh_addr, mod->build_id, - sechdr->sh_size)) - break; - } -} -#else -static void init_build_id(struct module *mod, const struct load_info *info) -{ -} -#endif - static void dynamic_debug_setup(struct module *mod, struct _ddebug *debug, unsigned int num) { if (!debug) @@ -2841,97 +1623,6 @@ bool __weak module_exit_section(const char *name) return strstarts(name, ".exit"); } -#ifdef CONFIG_DEBUG_KMEMLEAK -static void kmemleak_load_module(const struct module *mod, - const struct load_info *info) -{ - unsigned int i; - - /* only scan the sections containing data */ - kmemleak_scan_area(mod, sizeof(struct module), GFP_KERNEL); - - for (i = 1; i < info->hdr->e_shnum; i++) { - /* Scan all writable sections that's not executable */ - if (!(info->sechdrs[i].sh_flags & SHF_ALLOC) || - !(info->sechdrs[i].sh_flags & SHF_WRITE) || - (info->sechdrs[i].sh_flags & SHF_EXECINSTR)) - continue; - - kmemleak_scan_area((void *)info->sechdrs[i].sh_addr, - info->sechdrs[i].sh_size, GFP_KERNEL); - } -} -#else -static inline void kmemleak_load_module(const struct module *mod, - const struct load_info *info) -{ -} -#endif - -#ifdef CONFIG_MODULE_SIG -static int module_sig_check(struct load_info *info, int flags) -{ - int err = -ENODATA; - const unsigned long markerlen = sizeof(MODULE_SIG_STRING) - 1; - const char *reason; - const void *mod = info->hdr; - bool mangled_module = flags & (MODULE_INIT_IGNORE_MODVERSIONS | - MODULE_INIT_IGNORE_VERMAGIC); - /* - * Do not allow mangled modules as a module with version information - * removed is no longer the module that was signed. - */ - if (!mangled_module && - info->len > markerlen && - memcmp(mod + info->len - markerlen, MODULE_SIG_STRING, markerlen) == 0) { - /* We truncate the module to discard the signature */ - info->len -= markerlen; - err = mod_verify_sig(mod, info); - if (!err) { - info->sig_ok = true; - return 0; - } - } - - /* - * We don't permit modules to be loaded into the trusted kernels - * without a valid signature on them, but if we're not enforcing, - * certain errors are non-fatal. - */ - switch (err) { - case -ENODATA: - reason = "unsigned module"; - break; - case -ENOPKG: - reason = "module with unsupported crypto"; - break; - case -ENOKEY: - reason = "module with unavailable key"; - break; - - default: - /* - * All other errors are fatal, including lack of memory, - * unparseable signatures, and signature check failures -- - * even if signatures aren't required. - */ - return err; - } - - if (is_module_sig_enforced()) { - pr_notice("Loading of %s is rejected\n", reason); - return -EKEYREJECTED; - } - - return security_locked_down(LOCKDOWN_MODULE_SIGNATURE); -} -#else /* !CONFIG_MODULE_SIG */ -static int module_sig_check(struct load_info *info, int flags) -{ - return 0; -} -#endif /* !CONFIG_MODULE_SIG */ - static int validate_section_offset(struct load_info *info, Elf_Shdr *shdr) { #if defined(CONFIG_64BIT) @@ -3025,6 +1716,10 @@ static int elf_validity_check(struct load_info *info) * strings in the section safe. */ info->secstrings = (void *)info->hdr + strhdr->sh_offset; + if (strhdr->sh_size == 0) { + pr_err("empty section name table\n"); + goto no_exec; + } if (info->secstrings[strhdr->sh_size - 1] != '\0') { pr_err("ELF Spec violation: section name table isn't null terminated\n"); goto no_exec; @@ -3099,30 +1794,23 @@ static int copy_chunked_from_user(void *dst, const void __user *usrc, unsigned l return 0; } -#ifdef CONFIG_LIVEPATCH static int check_modinfo_livepatch(struct module *mod, struct load_info *info) { - if (get_modinfo(info, "livepatch")) { - mod->klp = true; + if (!get_modinfo(info, "livepatch")) + /* Nothing more to do */ + return 0; + + if (set_livepatch_module(mod)) { add_taint_module(mod, TAINT_LIVEPATCH, LOCKDEP_STILL_OK); pr_notice_once("%s: tainting kernel with TAINT_LIVEPATCH\n", - mod->name); - } - - return 0; -} -#else /* !CONFIG_LIVEPATCH */ -static int check_modinfo_livepatch(struct module *mod, struct load_info *info) -{ - if (get_modinfo(info, "livepatch")) { - pr_err("%s: module is marked as livepatch module, but livepatch support is disabled", - mod->name); - return -ENOEXEC; + mod->name); + return 0; } - return 0; + pr_err("%s: module is marked as livepatch module, but livepatch support is disabled", + mod->name); + return -ENOEXEC; } -#endif /* CONFIG_LIVEPATCH */ static void check_modinfo_retpoline(struct module *mod, struct load_info *info) { @@ -3448,6 +2136,24 @@ static int move_module(struct module *mod, struct load_info *info) } else mod->init_layout.base = NULL; +#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC + /* Do the allocs. */ + ptr = vmalloc(mod->data_layout.size); + /* + * The pointer to this block is stored in the module structure + * which is inside the block. Just mark it as not being a + * leak. + */ + kmemleak_not_leak(ptr); + if (!ptr) { + module_memfree(mod->core_layout.base); + module_memfree(mod->init_layout.base); + return -ENOMEM; + } + + memset(ptr, 0, mod->data_layout.size); + mod->data_layout.base = ptr; +#endif /* Transfer each section which specifies SHF_ALLOC */ pr_debug("final section addresses:\n"); for (i = 0; i < info->hdr->e_shnum; i++) { @@ -3460,6 +2166,8 @@ static int move_module(struct module *mod, struct load_info *info) if (shdr->sh_entsize & INIT_OFFSET_MASK) dest = mod->init_layout.base + (shdr->sh_entsize & ~INIT_OFFSET_MASK); + else if (!(shdr->sh_flags & SHF_EXECINSTR)) + dest = mod->data_layout.base + shdr->sh_entsize; else dest = mod->core_layout.base + shdr->sh_entsize; @@ -3621,6 +2329,9 @@ static void module_deallocate(struct module *mod, struct load_info *info) module_arch_freeing_init(mod); module_memfree(mod->init_layout.base); module_memfree(mod->core_layout.base); +#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC + vfree(mod->data_layout.base); +#endif } int __weak module_finalize(const Elf_Ehdr *hdr, @@ -3871,6 +2582,9 @@ static int complete_formation(struct module *mod, struct load_info *info) /* This relies on module_mutex for list integrity. */ module_bug_finalize(info->hdr, info->sechdrs, mod); + if (module_check_misalignment(mod)) + goto out_misaligned; + module_enable_ro(mod, false); module_enable_nx(mod); module_enable_x(mod); @@ -3884,6 +2598,8 @@ static int complete_formation(struct module *mod, struct load_info *info) return 0; +out_misaligned: + err = -EINVAL; out: mutex_unlock(&module_mutex); return err; @@ -4150,7 +2866,7 @@ static int load_module(struct load_info *info, const char __user *uargs, mutex_unlock(&module_mutex); free_module: /* Free lock-classes; relies on the preceding sync_rcu() */ - lockdep_free_key_range(mod->core_layout.base, mod->core_layout.size); + lockdep_free_key_range(mod->data_layout.base, mod->data_layout.size); module_deallocate(mod, info); free_copy: @@ -4219,287 +2935,6 @@ static inline int within(unsigned long addr, void *start, unsigned long size) return ((void *)addr >= start && (void *)addr < start + size); } -#ifdef CONFIG_KALLSYMS -/* - * This ignores the intensely annoying "mapping symbols" found - * in ARM ELF files: $a, $t and $d. - */ -static inline int is_arm_mapping_symbol(const char *str) -{ - if (str[0] == '.' && str[1] == 'L') - return true; - return str[0] == '$' && strchr("axtd", str[1]) - && (str[2] == '\0' || str[2] == '.'); -} - -static const char *kallsyms_symbol_name(struct mod_kallsyms *kallsyms, unsigned int symnum) -{ - return kallsyms->strtab + kallsyms->symtab[symnum].st_name; -} - -/* - * Given a module and address, find the corresponding symbol and return its name - * while providing its size and offset if needed. - */ -static const char *find_kallsyms_symbol(struct module *mod, - unsigned long addr, - unsigned long *size, - unsigned long *offset) -{ - unsigned int i, best = 0; - unsigned long nextval, bestval; - struct mod_kallsyms *kallsyms = rcu_dereference_sched(mod->kallsyms); - - /* At worse, next value is at end of module */ - if (within_module_init(addr, mod)) - nextval = (unsigned long)mod->init_layout.base+mod->init_layout.text_size; - else - nextval = (unsigned long)mod->core_layout.base+mod->core_layout.text_size; - - bestval = kallsyms_symbol_value(&kallsyms->symtab[best]); - - /* - * Scan for closest preceding symbol, and next symbol. (ELF - * starts real symbols at 1). - */ - for (i = 1; i < kallsyms->num_symtab; i++) { - const Elf_Sym *sym = &kallsyms->symtab[i]; - unsigned long thisval = kallsyms_symbol_value(sym); - - if (sym->st_shndx == SHN_UNDEF) - continue; - - /* - * We ignore unnamed symbols: they're uninformative - * and inserted at a whim. - */ - if (*kallsyms_symbol_name(kallsyms, i) == '\0' - || is_arm_mapping_symbol(kallsyms_symbol_name(kallsyms, i))) - continue; - - if (thisval <= addr && thisval > bestval) { - best = i; - bestval = thisval; - } - if (thisval > addr && thisval < nextval) - nextval = thisval; - } - - if (!best) - return NULL; - - if (size) - *size = nextval - bestval; - if (offset) - *offset = addr - bestval; - - return kallsyms_symbol_name(kallsyms, best); -} - -void * __weak dereference_module_function_descriptor(struct module *mod, - void *ptr) -{ - return ptr; -} - -/* - * For kallsyms to ask for address resolution. NULL means not found. Careful - * not to lock to avoid deadlock on oopses, simply disable preemption. - */ -const char *module_address_lookup(unsigned long addr, - unsigned long *size, - unsigned long *offset, - char **modname, - const unsigned char **modbuildid, - char *namebuf) -{ - const char *ret = NULL; - struct module *mod; - - preempt_disable(); - mod = __module_address(addr); - if (mod) { - if (modname) - *modname = mod->name; - if (modbuildid) { -#if IS_ENABLED(CONFIG_STACKTRACE_BUILD_ID) - *modbuildid = mod->build_id; -#else - *modbuildid = NULL; -#endif - } - - ret = find_kallsyms_symbol(mod, addr, size, offset); - } - /* Make a copy in here where it's safe */ - if (ret) { - strncpy(namebuf, ret, KSYM_NAME_LEN - 1); - ret = namebuf; - } - preempt_enable(); - - return ret; -} - -int lookup_module_symbol_name(unsigned long addr, char *symname) -{ - struct module *mod; - - preempt_disable(); - list_for_each_entry_rcu(mod, &modules, list) { - if (mod->state == MODULE_STATE_UNFORMED) - continue; - if (within_module(addr, mod)) { - const char *sym; - - sym = find_kallsyms_symbol(mod, addr, NULL, NULL); - if (!sym) - goto out; - - strlcpy(symname, sym, KSYM_NAME_LEN); - preempt_enable(); - return 0; - } - } -out: - preempt_enable(); - return -ERANGE; -} - -int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size, - unsigned long *offset, char *modname, char *name) -{ - struct module *mod; - - preempt_disable(); - list_for_each_entry_rcu(mod, &modules, list) { - if (mod->state == MODULE_STATE_UNFORMED) - continue; - if (within_module(addr, mod)) { - const char *sym; - - sym = find_kallsyms_symbol(mod, addr, size, offset); - if (!sym) - goto out; - if (modname) - strlcpy(modname, mod->name, MODULE_NAME_LEN); - if (name) - strlcpy(name, sym, KSYM_NAME_LEN); - preempt_enable(); - return 0; - } - } -out: - preempt_enable(); - return -ERANGE; -} - -int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type, - char *name, char *module_name, int *exported) -{ - struct module *mod; - - preempt_disable(); - list_for_each_entry_rcu(mod, &modules, list) { - struct mod_kallsyms *kallsyms; - - if (mod->state == MODULE_STATE_UNFORMED) - continue; - kallsyms = rcu_dereference_sched(mod->kallsyms); - if (symnum < kallsyms->num_symtab) { - const Elf_Sym *sym = &kallsyms->symtab[symnum]; - - *value = kallsyms_symbol_value(sym); - *type = kallsyms->typetab[symnum]; - strlcpy(name, kallsyms_symbol_name(kallsyms, symnum), KSYM_NAME_LEN); - strlcpy(module_name, mod->name, MODULE_NAME_LEN); - *exported = is_exported(name, *value, mod); - preempt_enable(); - return 0; - } - symnum -= kallsyms->num_symtab; - } - preempt_enable(); - return -ERANGE; -} - -/* Given a module and name of symbol, find and return the symbol's value */ -static unsigned long find_kallsyms_symbol_value(struct module *mod, const char *name) -{ - unsigned int i; - struct mod_kallsyms *kallsyms = rcu_dereference_sched(mod->kallsyms); - - for (i = 0; i < kallsyms->num_symtab; i++) { - const Elf_Sym *sym = &kallsyms->symtab[i]; - - if (strcmp(name, kallsyms_symbol_name(kallsyms, i)) == 0 && - sym->st_shndx != SHN_UNDEF) - return kallsyms_symbol_value(sym); - } - return 0; -} - -/* Look for this name: can be of form module:name. */ -unsigned long module_kallsyms_lookup_name(const char *name) -{ - struct module *mod; - char *colon; - unsigned long ret = 0; - - /* Don't lock: we're in enough trouble already. */ - preempt_disable(); - if ((colon = strnchr(name, MODULE_NAME_LEN, ':')) != NULL) { - if ((mod = find_module_all(name, colon - name, false)) != NULL) - ret = find_kallsyms_symbol_value(mod, colon+1); - } else { - list_for_each_entry_rcu(mod, &modules, list) { - if (mod->state == MODULE_STATE_UNFORMED) - continue; - if ((ret = find_kallsyms_symbol_value(mod, name)) != 0) - break; - } - } - preempt_enable(); - return ret; -} - -#ifdef CONFIG_LIVEPATCH -int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *, - struct module *, unsigned long), - void *data) -{ - struct module *mod; - unsigned int i; - int ret = 0; - - mutex_lock(&module_mutex); - list_for_each_entry(mod, &modules, list) { - /* We hold module_mutex: no need for rcu_dereference_sched */ - struct mod_kallsyms *kallsyms = mod->kallsyms; - - if (mod->state == MODULE_STATE_UNFORMED) - continue; - for (i = 0; i < kallsyms->num_symtab; i++) { - const Elf_Sym *sym = &kallsyms->symtab[i]; - - if (sym->st_shndx == SHN_UNDEF) - continue; - - ret = fn(data, kallsyms_symbol_name(kallsyms, i), - mod, kallsyms_symbol_value(sym)); - if (ret != 0) - goto out; - - cond_resched(); - } - } -out: - mutex_unlock(&module_mutex); - return ret; -} -#endif /* CONFIG_LIVEPATCH */ -#endif /* CONFIG_KALLSYMS */ - static void cfi_init(struct module *mod) { #ifdef CONFIG_CFI_CLANG @@ -4523,22 +2958,19 @@ static void cfi_init(struct module *mod) mod->exit = *exit; #endif - cfi_module_add(mod, module_addr_min); + cfi_module_add(mod, mod_tree.addr_min); #endif } static void cfi_cleanup(struct module *mod) { #ifdef CONFIG_CFI_CLANG - cfi_module_remove(mod, module_addr_min); + cfi_module_remove(mod, mod_tree.addr_min); #endif } -/* Maximum number of characters written by module_flags() */ -#define MODULE_FLAGS_BUF_SIZE (TAINT_FLAGS_COUNT + 4) - /* Keep in sync with MODULE_FLAGS_BUF_SIZE !!! */ -static char *module_flags(struct module *mod, char *buf) +char *module_flags(struct module *mod, char *buf) { int bx = 0; @@ -4547,7 +2979,7 @@ static char *module_flags(struct module *mod, char *buf) mod->state == MODULE_STATE_GOING || mod->state == MODULE_STATE_COMING) { buf[bx++] = '('; - bx += module_flags_taint(mod, buf + bx); + bx += module_flags_taint(mod->taints, buf + bx); /* Show a - for module-is-being-unloaded */ if (mod->state == MODULE_STATE_GOING) buf[bx++] = '-'; @@ -4561,103 +2993,6 @@ static char *module_flags(struct module *mod, char *buf) return buf; } -#ifdef CONFIG_PROC_FS -/* Called by the /proc file system to return a list of modules. */ -static void *m_start(struct seq_file *m, loff_t *pos) -{ - mutex_lock(&module_mutex); - return seq_list_start(&modules, *pos); -} - -static void *m_next(struct seq_file *m, void *p, loff_t *pos) -{ - return seq_list_next(p, &modules, pos); -} - -static void m_stop(struct seq_file *m, void *p) -{ - mutex_unlock(&module_mutex); -} - -static int m_show(struct seq_file *m, void *p) -{ - struct module *mod = list_entry(p, struct module, list); - char buf[MODULE_FLAGS_BUF_SIZE]; - void *value; - - /* We always ignore unformed modules. */ - if (mod->state == MODULE_STATE_UNFORMED) - return 0; - - seq_printf(m, "%s %u", - mod->name, mod->init_layout.size + mod->core_layout.size); - print_unload_info(m, mod); - - /* Informative for users. */ - seq_printf(m, " %s", - mod->state == MODULE_STATE_GOING ? "Unloading" : - mod->state == MODULE_STATE_COMING ? "Loading" : - "Live"); - /* Used by oprofile and other similar tools. */ - value = m->private ? NULL : mod->core_layout.base; - seq_printf(m, " 0x%px", value); - - /* Taints info */ - if (mod->taints) - seq_printf(m, " %s", module_flags(mod, buf)); - - seq_puts(m, "\n"); - return 0; -} - -/* - * Format: modulename size refcount deps address - * - * Where refcount is a number or -, and deps is a comma-separated list - * of depends or -. - */ -static const struct seq_operations modules_op = { - .start = m_start, - .next = m_next, - .stop = m_stop, - .show = m_show -}; - -/* - * This also sets the "private" pointer to non-NULL if the - * kernel pointers should be hidden (so you can just test - * "m->private" to see if you should keep the values private). - * - * We use the same logic as for /proc/kallsyms. - */ -static int modules_open(struct inode *inode, struct file *file) -{ - int err = seq_open(file, &modules_op); - - if (!err) { - struct seq_file *m = file->private_data; - m->private = kallsyms_show_value(file->f_cred) ? NULL : (void *)8ul; - } - - return err; -} - -static const struct proc_ops modules_proc_ops = { - .proc_flags = PROC_ENTRY_PERMANENT, - .proc_open = modules_open, - .proc_read = seq_read, - .proc_lseek = seq_lseek, - .proc_release = seq_release, -}; - -static int __init proc_modules_init(void) -{ - proc_create("modules", 0, NULL, &modules_proc_ops); - return 0; -} -module_init(proc_modules_init); -#endif - /* Given an address, look for it in the module exception tables. */ const struct exception_table_entry *search_module_extables(unsigned long addr) { @@ -4713,13 +3048,20 @@ bool is_module_address(unsigned long addr) struct module *__module_address(unsigned long addr) { struct module *mod; + struct mod_tree_root *tree; - if (addr < module_addr_min || addr > module_addr_max) + if (addr >= mod_tree.addr_min && addr <= mod_tree.addr_max) + tree = &mod_tree; +#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC + else if (addr >= mod_data_tree.addr_min && addr <= mod_data_tree.addr_max) + tree = &mod_data_tree; +#endif + else return NULL; module_assert_mutex_or_preempt(); - mod = mod_find(addr); + mod = mod_find(addr, tree); if (mod) { BUG_ON(!within_module(addr, mod)); if (mod->state == MODULE_STATE_UNFORMED) @@ -4780,23 +3122,10 @@ void print_modules(void) continue; pr_cont(" %s%s", mod->name, module_flags(mod, buf)); } + + print_unloaded_tainted_modules(); preempt_enable(); if (last_unloaded_module[0]) pr_cont(" [last unloaded: %s]", last_unloaded_module); pr_cont("\n"); } - -#ifdef CONFIG_MODVERSIONS -/* - * Generate the signature for all relevant module structures here. - * If these change, we don't want to try to parse the module. - */ -void module_layout(struct module *mod, - struct modversion_info *ver, - struct kernel_param *kp, - struct kernel_symbol *ks, - struct tracepoint * const *tp) -{ -} -EXPORT_SYMBOL(module_layout); -#endif diff --git a/kernel/module/procfs.c b/kernel/module/procfs.c new file mode 100644 index 000000000000..9a8f4f0f6329 --- /dev/null +++ b/kernel/module/procfs.c @@ -0,0 +1,146 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Module proc support + * + * Copyright (C) 2008 Alexey Dobriyan + */ + +#include <linux/module.h> +#include <linux/kallsyms.h> +#include <linux/mutex.h> +#include <linux/seq_file.h> +#include <linux/proc_fs.h> +#include "internal.h" + +#ifdef CONFIG_MODULE_UNLOAD +static inline void print_unload_info(struct seq_file *m, struct module *mod) +{ + struct module_use *use; + int printed_something = 0; + + seq_printf(m, " %i ", module_refcount(mod)); + + /* + * Always include a trailing , so userspace can differentiate + * between this and the old multi-field proc format. + */ + list_for_each_entry(use, &mod->source_list, source_list) { + printed_something = 1; + seq_printf(m, "%s,", use->source->name); + } + + if (mod->init && !mod->exit) { + printed_something = 1; + seq_puts(m, "[permanent],"); + } + + if (!printed_something) + seq_puts(m, "-"); +} +#else /* !CONFIG_MODULE_UNLOAD */ +static inline void print_unload_info(struct seq_file *m, struct module *mod) +{ + /* We don't know the usage count, or what modules are using. */ + seq_puts(m, " - -"); +} +#endif /* CONFIG_MODULE_UNLOAD */ + +/* Called by the /proc file system to return a list of modules. */ +static void *m_start(struct seq_file *m, loff_t *pos) +{ + mutex_lock(&module_mutex); + return seq_list_start(&modules, *pos); +} + +static void *m_next(struct seq_file *m, void *p, loff_t *pos) +{ + return seq_list_next(p, &modules, pos); +} + +static void m_stop(struct seq_file *m, void *p) +{ + mutex_unlock(&module_mutex); +} + +static int m_show(struct seq_file *m, void *p) +{ + struct module *mod = list_entry(p, struct module, list); + char buf[MODULE_FLAGS_BUF_SIZE]; + void *value; + unsigned int size; + + /* We always ignore unformed modules. */ + if (mod->state == MODULE_STATE_UNFORMED) + return 0; + + size = mod->init_layout.size + mod->core_layout.size; +#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC + size += mod->data_layout.size; +#endif + seq_printf(m, "%s %u", mod->name, size); + print_unload_info(m, mod); + + /* Informative for users. */ + seq_printf(m, " %s", + mod->state == MODULE_STATE_GOING ? "Unloading" : + mod->state == MODULE_STATE_COMING ? "Loading" : + "Live"); + /* Used by oprofile and other similar tools. */ + value = m->private ? NULL : mod->core_layout.base; + seq_printf(m, " 0x%px", value); + + /* Taints info */ + if (mod->taints) + seq_printf(m, " %s", module_flags(mod, buf)); + + seq_puts(m, "\n"); + return 0; +} + +/* + * Format: modulename size refcount deps address + * + * Where refcount is a number or -, and deps is a comma-separated list + * of depends or -. + */ +static const struct seq_operations modules_op = { + .start = m_start, + .next = m_next, + .stop = m_stop, + .show = m_show +}; + +/* + * This also sets the "private" pointer to non-NULL if the + * kernel pointers should be hidden (so you can just test + * "m->private" to see if you should keep the values private). + * + * We use the same logic as for /proc/kallsyms. + */ +static int modules_open(struct inode *inode, struct file *file) +{ + int err = seq_open(file, &modules_op); + + if (!err) { + struct seq_file *m = file->private_data; + + m->private = kallsyms_show_value(file->f_cred) ? NULL : (void *)8ul; + } + + return err; +} + +static const struct proc_ops modules_proc_ops = { + .proc_flags = PROC_ENTRY_PERMANENT, + .proc_open = modules_open, + .proc_read = seq_read, + .proc_lseek = seq_lseek, + .proc_release = seq_release, +}; + +static int __init proc_modules_init(void) +{ + proc_create("modules", 0, NULL, &modules_proc_ops); + return 0; +} +module_init(proc_modules_init); diff --git a/kernel/module/signing.c b/kernel/module/signing.c new file mode 100644 index 000000000000..85c8999dfecf --- /dev/null +++ b/kernel/module/signing.c @@ -0,0 +1,122 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* Module signature checker + * + * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + */ + +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/module.h> +#include <linux/module_signature.h> +#include <linux/string.h> +#include <linux/verification.h> +#include <linux/security.h> +#include <crypto/public_key.h> +#include <uapi/linux/module.h> +#include "internal.h" + +static bool sig_enforce = IS_ENABLED(CONFIG_MODULE_SIG_FORCE); +module_param(sig_enforce, bool_enable_only, 0644); + +/* + * Export sig_enforce kernel cmdline parameter to allow other subsystems rely + * on that instead of directly to CONFIG_MODULE_SIG_FORCE config. + */ +bool is_module_sig_enforced(void) +{ + return sig_enforce; +} +EXPORT_SYMBOL(is_module_sig_enforced); + +void set_module_sig_enforced(void) +{ + sig_enforce = true; +} + +/* + * Verify the signature on a module. + */ +int mod_verify_sig(const void *mod, struct load_info *info) +{ + struct module_signature ms; + size_t sig_len, modlen = info->len; + int ret; + + pr_devel("==>%s(,%zu)\n", __func__, modlen); + + if (modlen <= sizeof(ms)) + return -EBADMSG; + + memcpy(&ms, mod + (modlen - sizeof(ms)), sizeof(ms)); + + ret = mod_check_sig(&ms, modlen, "module"); + if (ret) + return ret; + + sig_len = be32_to_cpu(ms.sig_len); + modlen -= sig_len + sizeof(ms); + info->len = modlen; + + return verify_pkcs7_signature(mod, modlen, mod + modlen, sig_len, + VERIFY_USE_SECONDARY_KEYRING, + VERIFYING_MODULE_SIGNATURE, + NULL, NULL); +} + +int module_sig_check(struct load_info *info, int flags) +{ + int err = -ENODATA; + const unsigned long markerlen = sizeof(MODULE_SIG_STRING) - 1; + const char *reason; + const void *mod = info->hdr; + bool mangled_module = flags & (MODULE_INIT_IGNORE_MODVERSIONS | + MODULE_INIT_IGNORE_VERMAGIC); + /* + * Do not allow mangled modules as a module with version information + * removed is no longer the module that was signed. + */ + if (!mangled_module && + info->len > markerlen && + memcmp(mod + info->len - markerlen, MODULE_SIG_STRING, markerlen) == 0) { + /* We truncate the module to discard the signature */ + info->len -= markerlen; + err = mod_verify_sig(mod, info); + if (!err) { + info->sig_ok = true; + return 0; + } + } + + /* + * We don't permit modules to be loaded into the trusted kernels + * without a valid signature on them, but if we're not enforcing, + * certain errors are non-fatal. + */ + switch (err) { + case -ENODATA: + reason = "unsigned module"; + break; + case -ENOPKG: + reason = "module with unsupported crypto"; + break; + case -ENOKEY: + reason = "module with unavailable key"; + break; + + default: + /* + * All other errors are fatal, including lack of memory, + * unparseable signatures, and signature check failures -- + * even if signatures aren't required. + */ + return err; + } + + if (is_module_sig_enforced()) { + pr_notice("Loading of %s is rejected\n", reason); + return -EKEYREJECTED; + } + + return security_locked_down(LOCKDOWN_MODULE_SIGNATURE); +} diff --git a/kernel/module/strict_rwx.c b/kernel/module/strict_rwx.c new file mode 100644 index 000000000000..14fbea66f12f --- /dev/null +++ b/kernel/module/strict_rwx.c @@ -0,0 +1,143 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Module strict rwx + * + * Copyright (C) 2015 Rusty Russell + */ + +#include <linux/module.h> +#include <linux/mm.h> +#include <linux/vmalloc.h> +#include <linux/set_memory.h> +#include "internal.h" + +/* + * LKM RO/NX protection: protect module's text/ro-data + * from modification and any data from execution. + * + * General layout of module is: + * [text] [read-only-data] [ro-after-init] [writable data] + * text_size -----^ ^ ^ ^ + * ro_size ------------------------| | | + * ro_after_init_size -----------------------------| | + * size -----------------------------------------------------------| + * + * These values are always page-aligned (as is base) when + * CONFIG_STRICT_MODULE_RWX is set. + */ + +/* + * Since some arches are moving towards PAGE_KERNEL module allocations instead + * of PAGE_KERNEL_EXEC, keep frob_text() and module_enable_x() independent of + * CONFIG_STRICT_MODULE_RWX because they are needed regardless of whether we + * are strict. + */ +static void frob_text(const struct module_layout *layout, + int (*set_memory)(unsigned long start, int num_pages)) +{ + set_memory((unsigned long)layout->base, + PAGE_ALIGN(layout->text_size) >> PAGE_SHIFT); +} + +static void frob_rodata(const struct module_layout *layout, + int (*set_memory)(unsigned long start, int num_pages)) +{ + set_memory((unsigned long)layout->base + layout->text_size, + (layout->ro_size - layout->text_size) >> PAGE_SHIFT); +} + +static void frob_ro_after_init(const struct module_layout *layout, + int (*set_memory)(unsigned long start, int num_pages)) +{ + set_memory((unsigned long)layout->base + layout->ro_size, + (layout->ro_after_init_size - layout->ro_size) >> PAGE_SHIFT); +} + +static void frob_writable_data(const struct module_layout *layout, + int (*set_memory)(unsigned long start, int num_pages)) +{ + set_memory((unsigned long)layout->base + layout->ro_after_init_size, + (layout->size - layout->ro_after_init_size) >> PAGE_SHIFT); +} + +static bool layout_check_misalignment(const struct module_layout *layout) +{ + return WARN_ON(!PAGE_ALIGNED(layout->base)) || + WARN_ON(!PAGE_ALIGNED(layout->text_size)) || + WARN_ON(!PAGE_ALIGNED(layout->ro_size)) || + WARN_ON(!PAGE_ALIGNED(layout->ro_after_init_size)) || + WARN_ON(!PAGE_ALIGNED(layout->size)); +} + +bool module_check_misalignment(const struct module *mod) +{ + if (!IS_ENABLED(CONFIG_STRICT_MODULE_RWX)) + return false; + + return layout_check_misalignment(&mod->core_layout) || + layout_check_misalignment(&mod->data_layout) || + layout_check_misalignment(&mod->init_layout); +} + +void module_enable_x(const struct module *mod) +{ + if (!PAGE_ALIGNED(mod->core_layout.base) || + !PAGE_ALIGNED(mod->init_layout.base)) + return; + + frob_text(&mod->core_layout, set_memory_x); + frob_text(&mod->init_layout, set_memory_x); +} + +void module_enable_ro(const struct module *mod, bool after_init) +{ + if (!IS_ENABLED(CONFIG_STRICT_MODULE_RWX)) + return; +#ifdef CONFIG_STRICT_MODULE_RWX + if (!rodata_enabled) + return; +#endif + + set_vm_flush_reset_perms(mod->core_layout.base); + set_vm_flush_reset_perms(mod->init_layout.base); + frob_text(&mod->core_layout, set_memory_ro); + + frob_rodata(&mod->data_layout, set_memory_ro); + frob_text(&mod->init_layout, set_memory_ro); + frob_rodata(&mod->init_layout, set_memory_ro); + + if (after_init) + frob_ro_after_init(&mod->data_layout, set_memory_ro); +} + +void module_enable_nx(const struct module *mod) +{ + if (!IS_ENABLED(CONFIG_STRICT_MODULE_RWX)) + return; + + frob_rodata(&mod->data_layout, set_memory_nx); + frob_ro_after_init(&mod->data_layout, set_memory_nx); + frob_writable_data(&mod->data_layout, set_memory_nx); + frob_rodata(&mod->init_layout, set_memory_nx); + frob_writable_data(&mod->init_layout, set_memory_nx); +} + +int module_enforce_rwx_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs, + char *secstrings, struct module *mod) +{ + const unsigned long shf_wx = SHF_WRITE | SHF_EXECINSTR; + int i; + + if (!IS_ENABLED(CONFIG_STRICT_MODULE_RWX)) + return 0; + + for (i = 0; i < hdr->e_shnum; i++) { + if ((sechdrs[i].sh_flags & shf_wx) == shf_wx) { + pr_err("%s: section %s (index %d) has invalid WRITE|EXEC flags\n", + mod->name, secstrings + sechdrs[i].sh_name, i); + return -ENOEXEC; + } + } + + return 0; +} diff --git a/kernel/module/sysfs.c b/kernel/module/sysfs.c new file mode 100644 index 000000000000..ce68f821dcd1 --- /dev/null +++ b/kernel/module/sysfs.c @@ -0,0 +1,436 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Module sysfs support + * + * Copyright (C) 2008 Rusty Russell + */ + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/fs.h> +#include <linux/sysfs.h> +#include <linux/slab.h> +#include <linux/kallsyms.h> +#include <linux/mutex.h> +#include "internal.h" + +/* + * /sys/module/foo/sections stuff + * J. Corbet <corbet@lwn.net> + */ +#ifdef CONFIG_KALLSYMS +struct module_sect_attr { + struct bin_attribute battr; + unsigned long address; +}; + +struct module_sect_attrs { + struct attribute_group grp; + unsigned int nsections; + struct module_sect_attr attrs[]; +}; + +#define MODULE_SECT_READ_SIZE (3 /* "0x", "\n" */ + (BITS_PER_LONG / 4)) +static ssize_t module_sect_read(struct file *file, struct kobject *kobj, + struct bin_attribute *battr, + char *buf, loff_t pos, size_t count) +{ + struct module_sect_attr *sattr = + container_of(battr, struct module_sect_attr, battr); + char bounce[MODULE_SECT_READ_SIZE + 1]; + size_t wrote; + + if (pos != 0) + return -EINVAL; + + /* + * Since we're a binary read handler, we must account for the + * trailing NUL byte that sprintf will write: if "buf" is + * too small to hold the NUL, or the NUL is exactly the last + * byte, the read will look like it got truncated by one byte. + * Since there is no way to ask sprintf nicely to not write + * the NUL, we have to use a bounce buffer. + */ + wrote = scnprintf(bounce, sizeof(bounce), "0x%px\n", + kallsyms_show_value(file->f_cred) + ? (void *)sattr->address : NULL); + count = min(count, wrote); + memcpy(buf, bounce, count); + + return count; +} + +static void free_sect_attrs(struct module_sect_attrs *sect_attrs) +{ + unsigned int section; + + for (section = 0; section < sect_attrs->nsections; section++) + kfree(sect_attrs->attrs[section].battr.attr.name); + kfree(sect_attrs); +} + +static void add_sect_attrs(struct module *mod, const struct load_info *info) +{ + unsigned int nloaded = 0, i, size[2]; + struct module_sect_attrs *sect_attrs; + struct module_sect_attr *sattr; + struct bin_attribute **gattr; + + /* Count loaded sections and allocate structures */ + for (i = 0; i < info->hdr->e_shnum; i++) + if (!sect_empty(&info->sechdrs[i])) + nloaded++; + size[0] = ALIGN(struct_size(sect_attrs, attrs, nloaded), + sizeof(sect_attrs->grp.bin_attrs[0])); + size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.bin_attrs[0]); + sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL); + if (!sect_attrs) + return; + + /* Setup section attributes. */ + sect_attrs->grp.name = "sections"; + sect_attrs->grp.bin_attrs = (void *)sect_attrs + size[0]; + + sect_attrs->nsections = 0; + sattr = §_attrs->attrs[0]; + gattr = §_attrs->grp.bin_attrs[0]; + for (i = 0; i < info->hdr->e_shnum; i++) { + Elf_Shdr *sec = &info->sechdrs[i]; + + if (sect_empty(sec)) + continue; + sysfs_bin_attr_init(&sattr->battr); + sattr->address = sec->sh_addr; + sattr->battr.attr.name = + kstrdup(info->secstrings + sec->sh_name, GFP_KERNEL); + if (!sattr->battr.attr.name) + goto out; + sect_attrs->nsections++; + sattr->battr.read = module_sect_read; + sattr->battr.size = MODULE_SECT_READ_SIZE; + sattr->battr.attr.mode = 0400; + *(gattr++) = &(sattr++)->battr; + } + *gattr = NULL; + + if (sysfs_create_group(&mod->mkobj.kobj, §_attrs->grp)) + goto out; + + mod->sect_attrs = sect_attrs; + return; +out: + free_sect_attrs(sect_attrs); +} + +static void remove_sect_attrs(struct module *mod) +{ + if (mod->sect_attrs) { + sysfs_remove_group(&mod->mkobj.kobj, + &mod->sect_attrs->grp); + /* + * We are positive that no one is using any sect attrs + * at this point. Deallocate immediately. + */ + free_sect_attrs(mod->sect_attrs); + mod->sect_attrs = NULL; + } +} + +/* + * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections. + */ + +struct module_notes_attrs { + struct kobject *dir; + unsigned int notes; + struct bin_attribute attrs[]; +}; + +static ssize_t module_notes_read(struct file *filp, struct kobject *kobj, + struct bin_attribute *bin_attr, + char *buf, loff_t pos, size_t count) +{ + /* + * The caller checked the pos and count against our size. + */ + memcpy(buf, bin_attr->private + pos, count); + return count; +} + +static void free_notes_attrs(struct module_notes_attrs *notes_attrs, + unsigned int i) +{ + if (notes_attrs->dir) { + while (i-- > 0) + sysfs_remove_bin_file(notes_attrs->dir, + ¬es_attrs->attrs[i]); + kobject_put(notes_attrs->dir); + } + kfree(notes_attrs); +} + +static void add_notes_attrs(struct module *mod, const struct load_info *info) +{ + unsigned int notes, loaded, i; + struct module_notes_attrs *notes_attrs; + struct bin_attribute *nattr; + + /* failed to create section attributes, so can't create notes */ + if (!mod->sect_attrs) + return; + + /* Count notes sections and allocate structures. */ + notes = 0; + for (i = 0; i < info->hdr->e_shnum; i++) + if (!sect_empty(&info->sechdrs[i]) && + info->sechdrs[i].sh_type == SHT_NOTE) + ++notes; + + if (notes == 0) + return; + + notes_attrs = kzalloc(struct_size(notes_attrs, attrs, notes), + GFP_KERNEL); + if (!notes_attrs) + return; + + notes_attrs->notes = notes; + nattr = ¬es_attrs->attrs[0]; + for (loaded = i = 0; i < info->hdr->e_shnum; ++i) { + if (sect_empty(&info->sechdrs[i])) + continue; + if (info->sechdrs[i].sh_type == SHT_NOTE) { + sysfs_bin_attr_init(nattr); + nattr->attr.name = mod->sect_attrs->attrs[loaded].battr.attr.name; + nattr->attr.mode = 0444; + nattr->size = info->sechdrs[i].sh_size; + nattr->private = (void *)info->sechdrs[i].sh_addr; + nattr->read = module_notes_read; + ++nattr; + } + ++loaded; + } + + notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj); + if (!notes_attrs->dir) + goto out; + + for (i = 0; i < notes; ++i) + if (sysfs_create_bin_file(notes_attrs->dir, + ¬es_attrs->attrs[i])) + goto out; + + mod->notes_attrs = notes_attrs; + return; + +out: + free_notes_attrs(notes_attrs, i); +} + +static void remove_notes_attrs(struct module *mod) +{ + if (mod->notes_attrs) + free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes); +} + +#else /* !CONFIG_KALLSYMS */ +static inline void add_sect_attrs(struct module *mod, const struct load_info *info) { } +static inline void remove_sect_attrs(struct module *mod) { } +static inline void add_notes_attrs(struct module *mod, const struct load_info *info) { } +static inline void remove_notes_attrs(struct module *mod) { } +#endif /* CONFIG_KALLSYMS */ + +static void del_usage_links(struct module *mod) +{ +#ifdef CONFIG_MODULE_UNLOAD + struct module_use *use; + + mutex_lock(&module_mutex); + list_for_each_entry(use, &mod->target_list, target_list) + sysfs_remove_link(use->target->holders_dir, mod->name); + mutex_unlock(&module_mutex); +#endif +} + +static int add_usage_links(struct module *mod) +{ + int ret = 0; +#ifdef CONFIG_MODULE_UNLOAD + struct module_use *use; + + mutex_lock(&module_mutex); + list_for_each_entry(use, &mod->target_list, target_list) { + ret = sysfs_create_link(use->target->holders_dir, + &mod->mkobj.kobj, mod->name); + if (ret) + break; + } + mutex_unlock(&module_mutex); + if (ret) + del_usage_links(mod); +#endif + return ret; +} + +static void module_remove_modinfo_attrs(struct module *mod, int end) +{ + struct module_attribute *attr; + int i; + + for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) { + if (end >= 0 && i > end) + break; + /* pick a field to test for end of list */ + if (!attr->attr.name) + break; + sysfs_remove_file(&mod->mkobj.kobj, &attr->attr); + if (attr->free) + attr->free(mod); + } + kfree(mod->modinfo_attrs); +} + +static int module_add_modinfo_attrs(struct module *mod) +{ + struct module_attribute *attr; + struct module_attribute *temp_attr; + int error = 0; + int i; + + mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) * + (modinfo_attrs_count + 1)), + GFP_KERNEL); + if (!mod->modinfo_attrs) + return -ENOMEM; + + temp_attr = mod->modinfo_attrs; + for (i = 0; (attr = modinfo_attrs[i]); i++) { + if (!attr->test || attr->test(mod)) { + memcpy(temp_attr, attr, sizeof(*temp_attr)); + sysfs_attr_init(&temp_attr->attr); + error = sysfs_create_file(&mod->mkobj.kobj, + &temp_attr->attr); + if (error) + goto error_out; + ++temp_attr; + } + } + + return 0; + +error_out: + if (i > 0) + module_remove_modinfo_attrs(mod, --i); + else + kfree(mod->modinfo_attrs); + return error; +} + +static void mod_kobject_put(struct module *mod) +{ + DECLARE_COMPLETION_ONSTACK(c); + + mod->mkobj.kobj_completion = &c; + kobject_put(&mod->mkobj.kobj); + wait_for_completion(&c); +} + +static int mod_sysfs_init(struct module *mod) +{ + int err; + struct kobject *kobj; + + if (!module_sysfs_initialized) { + pr_err("%s: module sysfs not initialized\n", mod->name); + err = -EINVAL; + goto out; + } + + kobj = kset_find_obj(module_kset, mod->name); + if (kobj) { + pr_err("%s: module is already loaded\n", mod->name); + kobject_put(kobj); + err = -EINVAL; + goto out; + } + + mod->mkobj.mod = mod; + + memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj)); + mod->mkobj.kobj.kset = module_kset; + err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL, + "%s", mod->name); + if (err) + mod_kobject_put(mod); + +out: + return err; +} + +int mod_sysfs_setup(struct module *mod, + const struct load_info *info, + struct kernel_param *kparam, + unsigned int num_params) +{ + int err; + + err = mod_sysfs_init(mod); + if (err) + goto out; + + mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj); + if (!mod->holders_dir) { + err = -ENOMEM; + goto out_unreg; + } + + err = module_param_sysfs_setup(mod, kparam, num_params); + if (err) + goto out_unreg_holders; + + err = module_add_modinfo_attrs(mod); + if (err) + goto out_unreg_param; + + err = add_usage_links(mod); + if (err) + goto out_unreg_modinfo_attrs; + + add_sect_attrs(mod, info); + add_notes_attrs(mod, info); + + return 0; + +out_unreg_modinfo_attrs: + module_remove_modinfo_attrs(mod, -1); +out_unreg_param: + module_param_sysfs_remove(mod); +out_unreg_holders: + kobject_put(mod->holders_dir); +out_unreg: + mod_kobject_put(mod); +out: + return err; +} + +static void mod_sysfs_fini(struct module *mod) +{ + remove_notes_attrs(mod); + remove_sect_attrs(mod); + mod_kobject_put(mod); +} + +void mod_sysfs_teardown(struct module *mod) +{ + del_usage_links(mod); + module_remove_modinfo_attrs(mod, -1); + module_param_sysfs_remove(mod); + kobject_put(mod->mkobj.drivers_dir); + kobject_put(mod->holders_dir); + mod_sysfs_fini(mod); +} + +void init_param_lock(struct module *mod) +{ + mutex_init(&mod->param_lock); +} diff --git a/kernel/module/tracking.c b/kernel/module/tracking.c new file mode 100644 index 000000000000..7f8133044d09 --- /dev/null +++ b/kernel/module/tracking.c @@ -0,0 +1,61 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Module taint unload tracking support + * + * Copyright (C) 2022 Aaron Tomlin + */ + +#include <linux/module.h> +#include <linux/string.h> +#include <linux/printk.h> +#include <linux/slab.h> +#include <linux/list.h> +#include <linux/rculist.h> +#include "internal.h" + +static LIST_HEAD(unloaded_tainted_modules); + +int try_add_tainted_module(struct module *mod) +{ + struct mod_unload_taint *mod_taint; + + module_assert_mutex_or_preempt(); + + list_for_each_entry_rcu(mod_taint, &unloaded_tainted_modules, list, + lockdep_is_held(&module_mutex)) { + if (!strcmp(mod_taint->name, mod->name) && + mod_taint->taints & mod->taints) { + mod_taint->count++; + goto out; + } + } + + mod_taint = kmalloc(sizeof(*mod_taint), GFP_KERNEL); + if (unlikely(!mod_taint)) + return -ENOMEM; + strscpy(mod_taint->name, mod->name, MODULE_NAME_LEN); + mod_taint->taints = mod->taints; + list_add_rcu(&mod_taint->list, &unloaded_tainted_modules); + mod_taint->count = 1; +out: + return 0; +} + +void print_unloaded_tainted_modules(void) +{ + struct mod_unload_taint *mod_taint; + char buf[MODULE_FLAGS_BUF_SIZE]; + + if (!list_empty(&unloaded_tainted_modules)) { + printk(KERN_DEFAULT "Unloaded tainted modules:"); + list_for_each_entry_rcu(mod_taint, &unloaded_tainted_modules, + list) { + size_t l; + + l = module_flags_taint(mod_taint->taints, buf); + buf[l++] = '\0'; + pr_cont(" %s(%s):%llu", mod_taint->name, buf, + mod_taint->count); + } + } +} diff --git a/kernel/module/tree_lookup.c b/kernel/module/tree_lookup.c new file mode 100644 index 000000000000..8ec5cfd60496 --- /dev/null +++ b/kernel/module/tree_lookup.c @@ -0,0 +1,117 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Modules tree lookup + * + * Copyright (C) 2015 Peter Zijlstra + * Copyright (C) 2015 Rusty Russell + */ + +#include <linux/module.h> +#include <linux/rbtree_latch.h> +#include "internal.h" + +/* + * Use a latched RB-tree for __module_address(); this allows us to use + * RCU-sched lookups of the address from any context. + * + * This is conditional on PERF_EVENTS || TRACING because those can really hit + * __module_address() hard by doing a lot of stack unwinding; potentially from + * NMI context. + */ + +static __always_inline unsigned long __mod_tree_val(struct latch_tree_node *n) +{ + struct module_layout *layout = container_of(n, struct module_layout, mtn.node); + + return (unsigned long)layout->base; +} + +static __always_inline unsigned long __mod_tree_size(struct latch_tree_node *n) +{ + struct module_layout *layout = container_of(n, struct module_layout, mtn.node); + + return (unsigned long)layout->size; +} + +static __always_inline bool +mod_tree_less(struct latch_tree_node *a, struct latch_tree_node *b) +{ + return __mod_tree_val(a) < __mod_tree_val(b); +} + +static __always_inline int +mod_tree_comp(void *key, struct latch_tree_node *n) +{ + unsigned long val = (unsigned long)key; + unsigned long start, end; + + start = __mod_tree_val(n); + if (val < start) + return -1; + + end = start + __mod_tree_size(n); + if (val >= end) + return 1; + + return 0; +} + +static const struct latch_tree_ops mod_tree_ops = { + .less = mod_tree_less, + .comp = mod_tree_comp, +}; + +static noinline void __mod_tree_insert(struct mod_tree_node *node, struct mod_tree_root *tree) +{ + latch_tree_insert(&node->node, &tree->root, &mod_tree_ops); +} + +static void __mod_tree_remove(struct mod_tree_node *node, struct mod_tree_root *tree) +{ + latch_tree_erase(&node->node, &tree->root, &mod_tree_ops); +} + +/* + * These modifications: insert, remove_init and remove; are serialized by the + * module_mutex. + */ +void mod_tree_insert(struct module *mod) +{ + mod->core_layout.mtn.mod = mod; + mod->init_layout.mtn.mod = mod; + + __mod_tree_insert(&mod->core_layout.mtn, &mod_tree); + if (mod->init_layout.size) + __mod_tree_insert(&mod->init_layout.mtn, &mod_tree); + +#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC + mod->data_layout.mtn.mod = mod; + __mod_tree_insert(&mod->data_layout.mtn, &mod_data_tree); +#endif +} + +void mod_tree_remove_init(struct module *mod) +{ + if (mod->init_layout.size) + __mod_tree_remove(&mod->init_layout.mtn, &mod_tree); +} + +void mod_tree_remove(struct module *mod) +{ + __mod_tree_remove(&mod->core_layout.mtn, &mod_tree); + mod_tree_remove_init(mod); +#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC + __mod_tree_remove(&mod->data_layout.mtn, &mod_data_tree); +#endif +} + +struct module *mod_find(unsigned long addr, struct mod_tree_root *tree) +{ + struct latch_tree_node *ltn; + + ltn = latch_tree_find((void *)addr, &tree->root, &mod_tree_ops); + if (!ltn) + return NULL; + + return container_of(ltn, struct mod_tree_node, node)->mod; +} diff --git a/kernel/module/version.c b/kernel/module/version.c new file mode 100644 index 000000000000..53f43ac5a73e --- /dev/null +++ b/kernel/module/version.c @@ -0,0 +1,101 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Module version support + * + * Copyright (C) 2008 Rusty Russell + */ + +#include <linux/module.h> +#include <linux/string.h> +#include <linux/printk.h> +#include "internal.h" + +int check_version(const struct load_info *info, + const char *symname, + struct module *mod, + const s32 *crc) +{ + Elf_Shdr *sechdrs = info->sechdrs; + unsigned int versindex = info->index.vers; + unsigned int i, num_versions; + struct modversion_info *versions; + + /* Exporting module didn't supply crcs? OK, we're already tainted. */ + if (!crc) + return 1; + + /* No versions at all? modprobe --force does this. */ + if (versindex == 0) + return try_to_force_load(mod, symname) == 0; + + versions = (void *)sechdrs[versindex].sh_addr; + num_versions = sechdrs[versindex].sh_size + / sizeof(struct modversion_info); + + for (i = 0; i < num_versions; i++) { + u32 crcval; + + if (strcmp(versions[i].name, symname) != 0) + continue; + + crcval = *crc; + if (versions[i].crc == crcval) + return 1; + pr_debug("Found checksum %X vs module %lX\n", + crcval, versions[i].crc); + goto bad_version; + } + + /* Broken toolchain. Warn once, then let it go.. */ + pr_warn_once("%s: no symbol version for %s\n", info->name, symname); + return 1; + +bad_version: + pr_warn("%s: disagrees about version of symbol %s\n", info->name, symname); + return 0; +} + +int check_modstruct_version(const struct load_info *info, + struct module *mod) +{ + struct find_symbol_arg fsa = { + .name = "module_layout", + .gplok = true, + }; + + /* + * Since this should be found in kernel (which can't be removed), no + * locking is necessary -- use preempt_disable() to placate lockdep. + */ + preempt_disable(); + if (!find_symbol(&fsa)) { + preempt_enable(); + BUG(); + } + preempt_enable(); + return check_version(info, "module_layout", mod, fsa.crc); +} + +/* First part is kernel version, which we ignore if module has crcs. */ +int same_magic(const char *amagic, const char *bmagic, + bool has_crcs) +{ + if (has_crcs) { + amagic += strcspn(amagic, " "); + bmagic += strcspn(bmagic, " "); + } + return strcmp(amagic, bmagic) == 0; +} + +/* + * Generate the signature for all relevant module structures here. + * If these change, we don't want to try to parse the module. + */ +void module_layout(struct module *mod, + struct modversion_info *ver, + struct kernel_param *kp, + struct kernel_symbol *ks, + struct tracepoint * const *tp) +{ +} +EXPORT_SYMBOL(module_layout); diff --git a/kernel/module_signing.c b/kernel/module_signing.c deleted file mode 100644 index 8723ae70ea1f..000000000000 --- a/kernel/module_signing.c +++ /dev/null @@ -1,45 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-or-later -/* Module signature checker - * - * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved. - * Written by David Howells (dhowells@redhat.com) - */ - -#include <linux/kernel.h> -#include <linux/errno.h> -#include <linux/module.h> -#include <linux/module_signature.h> -#include <linux/string.h> -#include <linux/verification.h> -#include <crypto/public_key.h> -#include "module-internal.h" - -/* - * Verify the signature on a module. - */ -int mod_verify_sig(const void *mod, struct load_info *info) -{ - struct module_signature ms; - size_t sig_len, modlen = info->len; - int ret; - - pr_devel("==>%s(,%zu)\n", __func__, modlen); - - if (modlen <= sizeof(ms)) - return -EBADMSG; - - memcpy(&ms, mod + (modlen - sizeof(ms)), sizeof(ms)); - - ret = mod_check_sig(&ms, modlen, "module"); - if (ret) - return ret; - - sig_len = be32_to_cpu(ms.sig_len); - modlen -= sig_len + sizeof(ms); - info->len = modlen; - - return verify_pkcs7_signature(mod, modlen, mod + modlen, sig_len, - VERIFY_USE_SECONDARY_KEYRING, - VERIFYING_MODULE_SIGNATURE, - NULL, NULL); -} |