From 59e6e098d1c156f7c449af903c3b48a5470f6120 Mon Sep 17 00:00:00 2001 From: Andrey Konovalov Date: Mon, 5 Sep 2022 23:05:44 +0200 Subject: kasan: introduce kasan_complete_mode_report_info Add bug_type and alloc/free_track fields to kasan_report_info and add a kasan_complete_mode_report_info() function that fills in these fields. This function is implemented differently for different KASAN mode. Change the reporting code to use the filled in fields instead of invoking kasan_get_bug_type() and kasan_get_alloc/free_track(). For the Generic mode, kasan_complete_mode_report_info() invokes these functions instead. For the tag-based modes, only the bug_type field is filled in; alloc/free_track are handled in the next patch. Using a single function that fills in these fields is required for the tag-based modes, as the values for all three fields are determined in a single procedure implemented in the following patch. Link: https://lkml.kernel.org/r/8432b861054fa8d0cee79a8877dedeaf3b677ca8.1662411799.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov Reviewed-by: Marco Elver Cc: Alexander Potapenko Cc: Andrey Ryabinin Cc: Dmitry Vyukov Cc: Evgenii Stepanov Cc: Peter Collingbourne Signed-off-by: Andrew Morton --- mm/kasan/kasan.h | 33 +++++++++++++++++---------------- mm/kasan/report.c | 30 ++++++++++++++---------------- mm/kasan/report_generic.c | 32 +++++++++++++++++--------------- mm/kasan/report_tags.c | 13 +++---------- 4 files changed, 51 insertions(+), 57 deletions(-) (limited to 'mm') diff --git a/mm/kasan/kasan.h b/mm/kasan/kasan.h index b8fa1e50f3d4..7df107dc400a 100644 --- a/mm/kasan/kasan.h +++ b/mm/kasan/kasan.h @@ -146,6 +146,13 @@ static inline bool kasan_requires_meta(void) #define META_MEM_BYTES_PER_ROW (META_BYTES_PER_ROW * KASAN_GRANULE_SIZE) #define META_ROWS_AROUND_ADDR 2 +#define KASAN_STACK_DEPTH 64 + +struct kasan_track { + u32 pid; + depot_stack_handle_t stack; +}; + enum kasan_report_type { KASAN_REPORT_ACCESS, KASAN_REPORT_INVALID_FREE, @@ -164,6 +171,11 @@ struct kasan_report_info { void *first_bad_addr; struct kmem_cache *cache; void *object; + + /* Filled in by the mode-specific reporting code. */ + const char *bug_type; + struct kasan_track alloc_track; + struct kasan_track free_track; }; /* Do not change the struct layout: compiler ABI. */ @@ -189,14 +201,7 @@ struct kasan_global { #endif }; -/* Structures for keeping alloc and free tracks. */ - -#define KASAN_STACK_DEPTH 64 - -struct kasan_track { - u32 pid; - depot_stack_handle_t stack; -}; +/* Structures for keeping alloc and free meta. */ #ifdef CONFIG_KASAN_GENERIC @@ -270,16 +275,16 @@ static inline bool addr_has_metadata(const void *addr) #endif /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */ +void *kasan_find_first_bad_addr(void *addr, size_t size); +void kasan_complete_mode_report_info(struct kasan_report_info *info); +void kasan_metadata_fetch_row(char *buffer, void *row); + #if defined(CONFIG_KASAN_SW_TAGS) || defined(CONFIG_KASAN_HW_TAGS) void kasan_print_tags(u8 addr_tag, const void *addr); #else static inline void kasan_print_tags(u8 addr_tag, const void *addr) { } #endif -void *kasan_find_first_bad_addr(void *addr, size_t size); -const char *kasan_get_bug_type(struct kasan_report_info *info); -void kasan_metadata_fetch_row(char *buffer, void *row); - #if defined(CONFIG_KASAN_STACK) void kasan_print_address_stack_frame(const void *addr); #else @@ -314,10 +319,6 @@ depot_stack_handle_t kasan_save_stack(gfp_t flags, bool can_alloc); void kasan_set_track(struct kasan_track *track, gfp_t flags); void kasan_save_alloc_info(struct kmem_cache *cache, void *object, gfp_t flags); void kasan_save_free_info(struct kmem_cache *cache, void *object); -struct kasan_track *kasan_get_alloc_track(struct kmem_cache *cache, - void *object); -struct kasan_track *kasan_get_free_track(struct kmem_cache *cache, - void *object, u8 tag); #if defined(CONFIG_KASAN_GENERIC) && \ (defined(CONFIG_SLAB) || defined(CONFIG_SLUB)) diff --git a/mm/kasan/report.c b/mm/kasan/report.c index ec018f849992..39e8e5a80b82 100644 --- a/mm/kasan/report.c +++ b/mm/kasan/report.c @@ -185,8 +185,7 @@ static void print_error_description(struct kasan_report_info *info) return; } - pr_err("BUG: KASAN: %s in %pS\n", - kasan_get_bug_type(info), (void *)info->ip); + pr_err("BUG: KASAN: %s in %pS\n", info->bug_type, (void *)info->ip); if (info->access_size) pr_err("%s of size %zu at addr %px by task %s/%d\n", info->is_write ? "Write" : "Read", info->access_size, @@ -242,31 +241,25 @@ static void describe_object_addr(const void *addr, struct kmem_cache *cache, (void *)(object_addr + cache->object_size)); } -static void describe_object_stacks(u8 tag, struct kasan_report_info *info) +static void describe_object_stacks(struct kasan_report_info *info) { - struct kasan_track *alloc_track; - struct kasan_track *free_track; - - alloc_track = kasan_get_alloc_track(info->cache, info->object); - if (alloc_track) { - print_track(alloc_track, "Allocated"); + if (info->alloc_track.stack) { + print_track(&info->alloc_track, "Allocated"); pr_err("\n"); } - free_track = kasan_get_free_track(info->cache, info->object, tag); - if (free_track) { - print_track(free_track, "Freed"); + if (info->free_track.stack) { + print_track(&info->free_track, "Freed"); pr_err("\n"); } kasan_print_aux_stacks(info->cache, info->object); } -static void describe_object(const void *addr, u8 tag, - struct kasan_report_info *info) +static void describe_object(const void *addr, struct kasan_report_info *info) { if (kasan_stack_collection_enabled()) - describe_object_stacks(tag, info); + describe_object_stacks(info); describe_object_addr(addr, info->cache, info->object); } @@ -295,7 +288,7 @@ static void print_address_description(void *addr, u8 tag, pr_err("\n"); if (info->cache && info->object) { - describe_object(addr, tag, info); + describe_object(addr, info); pr_err("\n"); } @@ -426,6 +419,9 @@ static void complete_report_info(struct kasan_report_info *info) info->object = nearest_obj(info->cache, slab, addr); } else info->cache = info->object = NULL; + + /* Fill in mode-specific report info fields. */ + kasan_complete_mode_report_info(info); } void kasan_report_invalid_free(void *ptr, unsigned long ip, enum kasan_report_type type) @@ -443,6 +439,7 @@ void kasan_report_invalid_free(void *ptr, unsigned long ip, enum kasan_report_ty start_report(&flags, true); + memset(&info, 0, sizeof(info)); info.type = type; info.access_addr = ptr; info.access_size = 0; @@ -477,6 +474,7 @@ bool kasan_report(unsigned long addr, size_t size, bool is_write, start_report(&irq_flags, true); + memset(&info, 0, sizeof(info)); info.type = KASAN_REPORT_ACCESS; info.access_addr = ptr; info.access_size = size; diff --git a/mm/kasan/report_generic.c b/mm/kasan/report_generic.c index 74d21786ef09..087c1d8c8145 100644 --- a/mm/kasan/report_generic.c +++ b/mm/kasan/report_generic.c @@ -109,7 +109,7 @@ static const char *get_wild_bug_type(struct kasan_report_info *info) return bug_type; } -const char *kasan_get_bug_type(struct kasan_report_info *info) +static const char *get_bug_type(struct kasan_report_info *info) { /* * If access_size is a negative number, then it has reason to be @@ -127,25 +127,27 @@ const char *kasan_get_bug_type(struct kasan_report_info *info) return get_wild_bug_type(info); } -struct kasan_track *kasan_get_alloc_track(struct kmem_cache *cache, - void *object) +void kasan_complete_mode_report_info(struct kasan_report_info *info) { struct kasan_alloc_meta *alloc_meta; + struct kasan_free_meta *free_meta; - alloc_meta = kasan_get_alloc_meta(cache, object); - if (!alloc_meta) - return NULL; + info->bug_type = get_bug_type(info); - return &alloc_meta->alloc_track; -} + if (!info->cache || !info->object) + return; -struct kasan_track *kasan_get_free_track(struct kmem_cache *cache, - void *object, u8 tag) -{ - if (*(u8 *)kasan_mem_to_shadow(object) != KASAN_SLAB_FREETRACK) - return NULL; - /* Free meta must be present with KASAN_SLAB_FREETRACK. */ - return &kasan_get_free_meta(cache, object)->free_track; + alloc_meta = kasan_get_alloc_meta(info->cache, info->object); + if (alloc_meta) + memcpy(&info->alloc_track, &alloc_meta->alloc_track, + sizeof(info->alloc_track)); + + if (*(u8 *)kasan_mem_to_shadow(info->object) == KASAN_SLAB_FREETRACK) { + /* Free meta must be present with KASAN_SLAB_FREETRACK. */ + free_meta = kasan_get_free_meta(info->cache, info->object); + memcpy(&info->free_track, &free_meta->free_track, + sizeof(info->free_track)); + } } void kasan_metadata_fetch_row(char *buffer, void *row) diff --git a/mm/kasan/report_tags.c b/mm/kasan/report_tags.c index 79b6497d8a81..5cbac2cdb177 100644 --- a/mm/kasan/report_tags.c +++ b/mm/kasan/report_tags.c @@ -6,7 +6,7 @@ #include "kasan.h" -const char *kasan_get_bug_type(struct kasan_report_info *info) +static const char *get_bug_type(struct kasan_report_info *info) { /* * If access_size is a negative number, then it has reason to be @@ -22,14 +22,7 @@ const char *kasan_get_bug_type(struct kasan_report_info *info) return "invalid-access"; } -struct kasan_track *kasan_get_alloc_track(struct kmem_cache *cache, - void *object) +void kasan_complete_mode_report_info(struct kasan_report_info *info) { - return NULL; -} - -struct kasan_track *kasan_get_free_track(struct kmem_cache *cache, - void *object, u8 tag) -{ - return NULL; + info->bug_type = get_bug_type(info); } -- cgit