diff options
Diffstat (limited to 'arch/s390/mm/dump_pagetables.c')
| -rw-r--r-- | arch/s390/mm/dump_pagetables.c | 219 |
1 files changed, 116 insertions, 103 deletions
diff --git a/arch/s390/mm/dump_pagetables.c b/arch/s390/mm/dump_pagetables.c index ffd07ed7b4af..d3e943752fa0 100644 --- a/arch/s390/mm/dump_pagetables.c +++ b/arch/s390/mm/dump_pagetables.c @@ -1,8 +1,11 @@ // SPDX-License-Identifier: GPL-2.0 + +#include <linux/cpufeature.h> #include <linux/set_memory.h> #include <linux/ptdump.h> #include <linux/seq_file.h> #include <linux/debugfs.h> +#include <linux/sort.h> #include <linux/mm.h> #include <linux/kfence.h> #include <linux/kasan.h> @@ -15,68 +18,14 @@ static unsigned long max_addr; struct addr_marker { + int is_start; unsigned long start_address; + unsigned long size; const char *name; }; -enum address_markers_idx { - IDENTITY_BEFORE_NR = 0, - IDENTITY_BEFORE_END_NR, - AMODE31_START_NR, - AMODE31_END_NR, - KERNEL_START_NR, - KERNEL_END_NR, -#ifdef CONFIG_KFENCE - KFENCE_START_NR, - KFENCE_END_NR, -#endif - IDENTITY_AFTER_NR, - IDENTITY_AFTER_END_NR, - VMEMMAP_NR, - VMEMMAP_END_NR, - VMALLOC_NR, - VMALLOC_END_NR, - MODULES_NR, - MODULES_END_NR, - ABS_LOWCORE_NR, - ABS_LOWCORE_END_NR, - MEMCPY_REAL_NR, - MEMCPY_REAL_END_NR, -#ifdef CONFIG_KASAN - KASAN_SHADOW_START_NR, - KASAN_SHADOW_END_NR, -#endif -}; - -static struct addr_marker address_markers[] = { - [IDENTITY_BEFORE_NR] = {0, "Identity Mapping Start"}, - [IDENTITY_BEFORE_END_NR] = {(unsigned long)_stext, "Identity Mapping End"}, - [AMODE31_START_NR] = {0, "Amode31 Area Start"}, - [AMODE31_END_NR] = {0, "Amode31 Area End"}, - [KERNEL_START_NR] = {(unsigned long)_stext, "Kernel Image Start"}, - [KERNEL_END_NR] = {(unsigned long)_end, "Kernel Image End"}, -#ifdef CONFIG_KFENCE - [KFENCE_START_NR] = {0, "KFence Pool Start"}, - [KFENCE_END_NR] = {0, "KFence Pool End"}, -#endif - [IDENTITY_AFTER_NR] = {(unsigned long)_end, "Identity Mapping Start"}, - [IDENTITY_AFTER_END_NR] = {0, "Identity Mapping End"}, - [VMEMMAP_NR] = {0, "vmemmap Area Start"}, - [VMEMMAP_END_NR] = {0, "vmemmap Area End"}, - [VMALLOC_NR] = {0, "vmalloc Area Start"}, - [VMALLOC_END_NR] = {0, "vmalloc Area End"}, - [MODULES_NR] = {0, "Modules Area Start"}, - [MODULES_END_NR] = {0, "Modules Area End"}, - [ABS_LOWCORE_NR] = {0, "Lowcore Area Start"}, - [ABS_LOWCORE_END_NR] = {0, "Lowcore Area End"}, - [MEMCPY_REAL_NR] = {0, "Real Memory Copy Area Start"}, - [MEMCPY_REAL_END_NR] = {0, "Real Memory Copy Area End"}, -#ifdef CONFIG_KASAN - [KASAN_SHADOW_START_NR] = {KASAN_SHADOW_START, "Kasan Shadow Start"}, - [KASAN_SHADOW_END_NR] = {KASAN_SHADOW_END, "Kasan Shadow End"}, -#endif - { -1, NULL } -}; +static struct addr_marker *markers; +static unsigned int markers_cnt; struct pg_state { struct ptdump_state ptdump; @@ -135,7 +84,7 @@ static void note_prot_wx(struct pg_state *st, unsigned long addr) * in which case we have two lpswe instructions in lowcore that need * to be executable. */ - if (addr == PAGE_SIZE && (nospec_uses_trampoline() || !static_key_enabled(&cpu_has_bear))) + if (addr == PAGE_SIZE && (nospec_uses_trampoline() || !cpu_has_bear())) return; WARN_ONCE(IS_ENABLED(CONFIG_DEBUG_WX), "s390/mm: Found insecure W+X mapping at address %pS\n", @@ -143,6 +92,20 @@ static void note_prot_wx(struct pg_state *st, unsigned long addr) st->wx_pages += (addr - st->start_address) / PAGE_SIZE; } +static void note_page_update_state(struct pg_state *st, unsigned long addr, unsigned int prot, int level) +{ + struct seq_file *m = st->seq; + + while (addr >= st->marker[1].start_address) { + st->marker++; + pt_dump_seq_printf(m, "---[ %s %s ]---\n", st->marker->name, + st->marker->is_start ? "Start" : "End"); + } + st->start_address = addr; + st->current_prot = prot; + st->level = level; +} + static void note_page(struct ptdump_state *pt_st, unsigned long addr, int level, u64 val) { int width = sizeof(unsigned long) * 2; @@ -165,10 +128,8 @@ static void note_page(struct ptdump_state *pt_st, unsigned long addr, int level, if (level == -1) addr = max_addr; if (st->level == -1) { - pt_dump_seq_printf(m, "---[ %s ]---\n", st->marker->name); - st->start_address = addr; - st->current_prot = prot; - st->level = level; + pt_dump_seq_puts(m, "---[ Kernel Virtual Address Space ]---\n"); + note_page_update_state(st, addr, prot, level); } else if (prot != st->current_prot || level != st->level || addr >= st->marker[1].start_address) { note_prot_wx(st, addr); @@ -182,13 +143,7 @@ static void note_page(struct ptdump_state *pt_st, unsigned long addr, int level, } pt_dump_seq_printf(m, "%9lu%c ", delta, *unit); print_prot(m, st->current_prot, st->level); - while (addr >= st->marker[1].start_address) { - st->marker++; - pt_dump_seq_printf(m, "---[ %s ]---\n", st->marker->name); - } - st->start_address = addr; - st->current_prot = prot; - st->level = level; + note_page_update_state(st, addr, prot, level); } } @@ -214,7 +169,7 @@ bool ptdump_check_wx(void) }, }; - if (!MACHINE_HAS_NX) + if (!cpu_has_nx()) return true; ptdump_walk_pgd(&st.ptdump, &init_mm, NULL); if (st.wx_pages) { @@ -223,7 +178,7 @@ bool ptdump_check_wx(void) return false; } else { pr_info("Checked W+X mappings: passed, no %sW+X pages found\n", - (nospec_uses_trampoline() || !static_key_enabled(&cpu_has_bear)) ? + (nospec_uses_trampoline() || !cpu_has_bear()) ? "unexpected " : ""); return true; @@ -247,7 +202,7 @@ static int ptdump_show(struct seq_file *m, void *v) .check_wx = false, .wx_pages = 0, .start_address = 0, - .marker = address_markers, + .marker = markers, }; get_online_mems(); @@ -260,22 +215,66 @@ static int ptdump_show(struct seq_file *m, void *v) DEFINE_SHOW_ATTRIBUTE(ptdump); #endif /* CONFIG_PTDUMP_DEBUGFS */ -/* - * Heapsort from lib/sort.c is not a stable sorting algorithm, do a simple - * insertion sort to preserve the original order of markers with the same - * start address. - */ -static void sort_address_markers(void) +static int ptdump_cmp(const void *a, const void *b) { - struct addr_marker tmp; - int i, j; + const struct addr_marker *ama = a; + const struct addr_marker *amb = b; - for (i = 1; i < ARRAY_SIZE(address_markers) - 1; i++) { - tmp = address_markers[i]; - for (j = i - 1; j >= 0 && address_markers[j].start_address > tmp.start_address; j--) - address_markers[j + 1] = address_markers[j]; - address_markers[j + 1] = tmp; + if (ama->start_address > amb->start_address) + return 1; + if (ama->start_address < amb->start_address) + return -1; + /* + * If the start addresses of two markers are identical sort markers in an + * order that considers areas contained within other areas correctly. + */ + if (ama->is_start && amb->is_start) { + if (ama->size > amb->size) + return -1; + if (ama->size < amb->size) + return 1; + return 0; } + if (!ama->is_start && !amb->is_start) { + if (ama->size > amb->size) + return 1; + if (ama->size < amb->size) + return -1; + return 0; + } + if (ama->is_start) + return 1; + if (amb->is_start) + return -1; + return 0; +} + +static int add_marker(unsigned long start, unsigned long end, const char *name) +{ + size_t oldsize, newsize; + + oldsize = markers_cnt * sizeof(*markers); + newsize = oldsize + 2 * sizeof(*markers); + if (!oldsize) + markers = kvmalloc(newsize, GFP_KERNEL); + else + markers = kvrealloc(markers, newsize, GFP_KERNEL); + if (!markers) + goto error; + markers[markers_cnt].is_start = 1; + markers[markers_cnt].start_address = start; + markers[markers_cnt].size = end - start; + markers[markers_cnt].name = name; + markers_cnt++; + markers[markers_cnt].is_start = 0; + markers[markers_cnt].start_address = end; + markers[markers_cnt].size = end - start; + markers[markers_cnt].name = name; + markers_cnt++; + return 0; +error: + markers_cnt = 0; + return -ENOMEM; } static int pt_dump_init(void) @@ -283,34 +282,48 @@ static int pt_dump_init(void) #ifdef CONFIG_KFENCE unsigned long kfence_start = (unsigned long)__kfence_pool; #endif + unsigned long lowcore = (unsigned long)get_lowcore(); + int rc; + /* * Figure out the maximum virtual address being accessible with the * kernel ASCE. We need this to keep the page table walker functions * from accessing non-existent entries. */ - max_addr = (S390_lowcore.kernel_asce.val & _REGION_ENTRY_TYPE_MASK) >> 2; + max_addr = (get_lowcore()->kernel_asce.val & _REGION_ENTRY_TYPE_MASK) >> 2; max_addr = 1UL << (max_addr * 11 + 31); - address_markers[IDENTITY_AFTER_END_NR].start_address = ident_map_size; - address_markers[AMODE31_START_NR].start_address = (unsigned long)__samode31; - address_markers[AMODE31_END_NR].start_address = (unsigned long)__eamode31; - address_markers[MODULES_NR].start_address = MODULES_VADDR; - address_markers[MODULES_END_NR].start_address = MODULES_END; - address_markers[ABS_LOWCORE_NR].start_address = __abs_lowcore; - address_markers[ABS_LOWCORE_END_NR].start_address = __abs_lowcore + ABS_LOWCORE_MAP_SIZE; - address_markers[MEMCPY_REAL_NR].start_address = __memcpy_real_area; - address_markers[MEMCPY_REAL_END_NR].start_address = __memcpy_real_area + MEMCPY_REAL_SIZE; - address_markers[VMEMMAP_NR].start_address = (unsigned long) vmemmap; - address_markers[VMEMMAP_END_NR].start_address = (unsigned long)vmemmap + vmemmap_size; - address_markers[VMALLOC_NR].start_address = VMALLOC_START; - address_markers[VMALLOC_END_NR].start_address = VMALLOC_END; + /* start + end markers - must be added first */ + rc = add_marker(0, -1UL, NULL); + rc |= add_marker((unsigned long)_stext, (unsigned long)_end, "Kernel Image"); + rc |= add_marker(lowcore, lowcore + sizeof(struct lowcore), "Lowcore"); + rc |= add_marker(__identity_base, __identity_base + ident_map_size, "Identity Mapping"); + rc |= add_marker((unsigned long)__samode31, (unsigned long)__eamode31, "Amode31 Area"); + rc |= add_marker(MODULES_VADDR, MODULES_END, "Modules Area"); + rc |= add_marker(__abs_lowcore, __abs_lowcore + ABS_LOWCORE_MAP_SIZE, "Lowcore Area"); + rc |= add_marker(__memcpy_real_area, __memcpy_real_area + MEMCPY_REAL_SIZE, "Real Memory Copy Area"); + rc |= add_marker((unsigned long)vmemmap, (unsigned long)vmemmap + vmemmap_size, "vmemmap Area"); + rc |= add_marker(VMALLOC_START, VMALLOC_END, "vmalloc Area"); #ifdef CONFIG_KFENCE - address_markers[KFENCE_START_NR].start_address = kfence_start; - address_markers[KFENCE_END_NR].start_address = kfence_start + KFENCE_POOL_SIZE; + rc |= add_marker(kfence_start, kfence_start + KFENCE_POOL_SIZE, "KFence Pool"); +#endif +#ifdef CONFIG_KMSAN + rc |= add_marker(KMSAN_VMALLOC_SHADOW_START, KMSAN_VMALLOC_SHADOW_END, "Kmsan vmalloc Shadow"); + rc |= add_marker(KMSAN_VMALLOC_ORIGIN_START, KMSAN_VMALLOC_ORIGIN_END, "Kmsan vmalloc Origins"); + rc |= add_marker(KMSAN_MODULES_SHADOW_START, KMSAN_MODULES_SHADOW_END, "Kmsan Modules Shadow"); + rc |= add_marker(KMSAN_MODULES_ORIGIN_START, KMSAN_MODULES_ORIGIN_END, "Kmsan Modules Origins"); +#endif +#ifdef CONFIG_KASAN + rc |= add_marker(KASAN_SHADOW_START, KASAN_SHADOW_END, "Kasan Shadow"); #endif - sort_address_markers(); + if (rc) + goto error; + sort(&markers[1], markers_cnt - 1, sizeof(*markers), ptdump_cmp, NULL); #ifdef CONFIG_PTDUMP_DEBUGFS debugfs_create_file("kernel_page_tables", 0400, NULL, NULL, &ptdump_fops); #endif /* CONFIG_PTDUMP_DEBUGFS */ return 0; +error: + kvfree(markers); + return -ENOMEM; } device_initcall(pt_dump_init); |