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authorLinus Torvalds <torvalds@linux-foundation.org>2021-11-09 10:11:53 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2021-11-09 10:11:53 -0800
commit59a2ceeef6d6bb8f68550fdbd84246b74a99f06b (patch)
treed8302a240dfe56defb8d56df555bb046a5a7bb5c /fs/binfmt_elf.c
parentd2f38a3c6507b2520101f9a3807ed98f1bdc545a (diff)
parent0e9beb8a96f21a6df1579cb3a679e150e3269d80 (diff)
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Merge branch 'akpm' (patches from Andrew)
Merge more updates from Andrew Morton: "87 patches. Subsystems affected by this patch series: mm (pagecache and hugetlb), procfs, misc, MAINTAINERS, lib, checkpatch, binfmt, kallsyms, ramfs, init, codafs, nilfs2, hfs, crash_dump, signals, seq_file, fork, sysvfs, kcov, gdb, resource, selftests, and ipc" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (87 commits) ipc/ipc_sysctl.c: remove fallback for !CONFIG_PROC_SYSCTL ipc: check checkpoint_restore_ns_capable() to modify C/R proc files selftests/kselftest/runner/run_one(): allow running non-executable files virtio-mem: disallow mapping virtio-mem memory via /dev/mem kernel/resource: disallow access to exclusive system RAM regions kernel/resource: clean up and optimize iomem_is_exclusive() scripts/gdb: handle split debug for vmlinux kcov: replace local_irq_save() with a local_lock_t kcov: avoid enable+disable interrupts if !in_task() kcov: allocate per-CPU memory on the relevant node Documentation/kcov: define `ip' in the example Documentation/kcov: include types.h in the example sysv: use BUILD_BUG_ON instead of runtime check kernel/fork.c: unshare(): use swap() to make code cleaner seq_file: fix passing wrong private data seq_file: move seq_escape() to a header signal: remove duplicate include in signal.h crash_dump: remove duplicate include in crash_dump.h crash_dump: fix boolreturn.cocci warning hfs/hfsplus: use WARN_ON for sanity check ...
Diffstat (limited to 'fs/binfmt_elf.c')
-rw-r--r--fs/binfmt_elf.c33
1 files changed, 23 insertions, 10 deletions
diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c
index fa582748be41..f8c7f26f1fbb 100644
--- a/fs/binfmt_elf.c
+++ b/fs/binfmt_elf.c
@@ -156,7 +156,7 @@ static int padzero(unsigned long elf_bss)
#define STACK_ADD(sp, items) ((elf_addr_t __user *)(sp) - (items))
#define STACK_ROUND(sp, items) \
(((unsigned long) (sp - items)) &~ 15UL)
-#define STACK_ALLOC(sp, len) ({ sp -= len ; sp; })
+#define STACK_ALLOC(sp, len) (sp -= len)
#endif
#ifndef ELF_BASE_PLATFORM
@@ -1074,20 +1074,26 @@ out_free_interp:
vaddr = elf_ppnt->p_vaddr;
/*
- * If we are loading ET_EXEC or we have already performed
- * the ET_DYN load_addr calculations, proceed normally.
+ * The first time through the loop, load_addr_set is false:
+ * layout will be calculated. Once set, use MAP_FIXED since
+ * we know we've already safely mapped the entire region with
+ * MAP_FIXED_NOREPLACE in the once-per-binary logic following.
*/
- if (elf_ex->e_type == ET_EXEC || load_addr_set) {
+ if (load_addr_set) {
elf_flags |= MAP_FIXED;
+ } else if (elf_ex->e_type == ET_EXEC) {
+ /*
+ * This logic is run once for the first LOAD Program
+ * Header for ET_EXEC binaries. No special handling
+ * is needed.
+ */
+ elf_flags |= MAP_FIXED_NOREPLACE;
} else if (elf_ex->e_type == ET_DYN) {
/*
* This logic is run once for the first LOAD Program
* Header for ET_DYN binaries to calculate the
* randomization (load_bias) for all the LOAD
- * Program Headers, and to calculate the entire
- * size of the ELF mapping (total_size). (Note that
- * load_addr_set is set to true later once the
- * initial mapping is performed.)
+ * Program Headers.
*
* There are effectively two types of ET_DYN
* binaries: programs (i.e. PIE: ET_DYN with INTERP)
@@ -1108,7 +1114,7 @@ out_free_interp:
* Therefore, programs are loaded offset from
* ELF_ET_DYN_BASE and loaders are loaded into the
* independently randomized mmap region (0 load_bias
- * without MAP_FIXED).
+ * without MAP_FIXED nor MAP_FIXED_NOREPLACE).
*/
if (interpreter) {
load_bias = ELF_ET_DYN_BASE;
@@ -1117,7 +1123,7 @@ out_free_interp:
alignment = maximum_alignment(elf_phdata, elf_ex->e_phnum);
if (alignment)
load_bias &= ~(alignment - 1);
- elf_flags |= MAP_FIXED;
+ elf_flags |= MAP_FIXED_NOREPLACE;
} else
load_bias = 0;
@@ -1129,7 +1135,14 @@ out_free_interp:
* is then page aligned.
*/
load_bias = ELF_PAGESTART(load_bias - vaddr);
+ }
+ /*
+ * Calculate the entire size of the ELF mapping (total_size).
+ * (Note that load_addr_set is set to true later once the
+ * initial mapping is performed.)
+ */
+ if (!load_addr_set) {
total_size = total_mapping_size(elf_phdata,
elf_ex->e_phnum);
if (!total_size) {