diff options
| -rw-r--r-- | include/linux/stackdepot.h | 36 | ||||
| -rw-r--r-- | lib/stackdepot.c | 16 | ||||
| -rw-r--r-- | mm/kasan/common.c | 7 | ||||
| -rw-r--r-- | mm/kasan/generic.c | 9 | ||||
| -rw-r--r-- | mm/kasan/kasan.h | 2 | ||||
| -rw-r--r-- | mm/kasan/tags.c | 3 |
6 files changed, 48 insertions, 25 deletions
diff --git a/include/linux/stackdepot.h b/include/linux/stackdepot.h index e58306783d8e..0b262e14144e 100644 --- a/include/linux/stackdepot.h +++ b/include/linux/stackdepot.h @@ -32,6 +32,17 @@ typedef u32 depot_stack_handle_t; */ #define STACK_DEPOT_EXTRA_BITS 5 +typedef u32 depot_flags_t; + +/* + * Flags that can be passed to stack_depot_save_flags(); see the comment next + * to its declaration for more details. + */ +#define STACK_DEPOT_FLAG_CAN_ALLOC ((depot_flags_t)0x0001) + +#define STACK_DEPOT_FLAGS_NUM 1 +#define STACK_DEPOT_FLAGS_MASK ((depot_flags_t)((1 << STACK_DEPOT_FLAGS_NUM) - 1)) + /* * Using stack depot requires its initialization, which can be done in 3 ways: * @@ -69,31 +80,34 @@ static inline int stack_depot_early_init(void) { return 0; } #endif /** - * __stack_depot_save - Save a stack trace to stack depot + * stack_depot_save_flags - Save a stack trace to stack depot * * @entries: Pointer to the stack trace * @nr_entries: Number of frames in the stack * @alloc_flags: Allocation GFP flags - * @can_alloc: Allocate stack pools (increased chance of failure if false) + * @depot_flags: Stack depot flags + * + * Saves a stack trace from @entries array of size @nr_entries. * - * Saves a stack trace from @entries array of size @nr_entries. If @can_alloc is - * %true, stack depot can replenish the stack pools in case no space is left - * (allocates using GFP flags of @alloc_flags). If @can_alloc is %false, avoids - * any allocations and fails if no space is left to store the stack trace. + * If STACK_DEPOT_FLAG_CAN_ALLOC is set in @depot_flags, stack depot can + * replenish the stack pools in case no space is left (allocates using GFP + * flags of @alloc_flags). Otherwise, stack depot avoids any allocations and + * fails if no space is left to store the stack trace. * * If the provided stack trace comes from the interrupt context, only the part * up to the interrupt entry is saved. * - * Context: Any context, but setting @can_alloc to %false is required if + * Context: Any context, but setting STACK_DEPOT_FLAG_CAN_ALLOC is required if * alloc_pages() cannot be used from the current context. Currently * this is the case for contexts where neither %GFP_ATOMIC nor * %GFP_NOWAIT can be used (NMI, raw_spin_lock). * * Return: Handle of the stack struct stored in depot, 0 on failure */ -depot_stack_handle_t __stack_depot_save(unsigned long *entries, - unsigned int nr_entries, - gfp_t gfp_flags, bool can_alloc); +depot_stack_handle_t stack_depot_save_flags(unsigned long *entries, + unsigned int nr_entries, + gfp_t gfp_flags, + depot_flags_t depot_flags); /** * stack_depot_save - Save a stack trace to stack depot @@ -103,7 +117,7 @@ depot_stack_handle_t __stack_depot_save(unsigned long *entries, * @alloc_flags: Allocation GFP flags * * Context: Contexts where allocations via alloc_pages() are allowed. - * See __stack_depot_save() for more details. + * See stack_depot_save_flags() for more details. * * Return: Handle of the stack trace stored in depot, 0 on failure */ diff --git a/lib/stackdepot.c b/lib/stackdepot.c index 4bb0af423f82..59d61d5c09a7 100644 --- a/lib/stackdepot.c +++ b/lib/stackdepot.c @@ -450,19 +450,24 @@ static inline struct stack_record *find_stack(struct list_head *bucket, return NULL; } -depot_stack_handle_t __stack_depot_save(unsigned long *entries, - unsigned int nr_entries, - gfp_t alloc_flags, bool can_alloc) +depot_stack_handle_t stack_depot_save_flags(unsigned long *entries, + unsigned int nr_entries, + gfp_t alloc_flags, + depot_flags_t depot_flags) { struct list_head *bucket; struct stack_record *found = NULL; depot_stack_handle_t handle = 0; struct page *page = NULL; void *prealloc = NULL; + bool can_alloc = depot_flags & STACK_DEPOT_FLAG_CAN_ALLOC; bool need_alloc = false; unsigned long flags; u32 hash; + if (WARN_ON(depot_flags & ~STACK_DEPOT_FLAGS_MASK)) + return 0; + /* * If this stack trace is from an interrupt, including anything before * interrupt entry usually leads to unbounded stack depot growth. @@ -541,13 +546,14 @@ exit: handle = found->handle.handle; return handle; } -EXPORT_SYMBOL_GPL(__stack_depot_save); +EXPORT_SYMBOL_GPL(stack_depot_save_flags); depot_stack_handle_t stack_depot_save(unsigned long *entries, unsigned int nr_entries, gfp_t alloc_flags) { - return __stack_depot_save(entries, nr_entries, alloc_flags, true); + return stack_depot_save_flags(entries, nr_entries, alloc_flags, + STACK_DEPOT_FLAG_CAN_ALLOC); } EXPORT_SYMBOL_GPL(stack_depot_save); diff --git a/mm/kasan/common.c b/mm/kasan/common.c index 256930da578a..825a0240ec02 100644 --- a/mm/kasan/common.c +++ b/mm/kasan/common.c @@ -22,6 +22,7 @@ #include <linux/sched.h> #include <linux/sched/task_stack.h> #include <linux/slab.h> +#include <linux/stackdepot.h> #include <linux/stacktrace.h> #include <linux/string.h> #include <linux/types.h> @@ -37,19 +38,19 @@ struct slab *kasan_addr_to_slab(const void *addr) return NULL; } -depot_stack_handle_t kasan_save_stack(gfp_t flags, bool can_alloc) +depot_stack_handle_t kasan_save_stack(gfp_t flags, depot_flags_t depot_flags) { unsigned long entries[KASAN_STACK_DEPTH]; unsigned int nr_entries; nr_entries = stack_trace_save(entries, ARRAY_SIZE(entries), 0); - return __stack_depot_save(entries, nr_entries, flags, can_alloc); + return stack_depot_save_flags(entries, nr_entries, flags, depot_flags); } void kasan_set_track(struct kasan_track *track, gfp_t flags) { track->pid = current->pid; - track->stack = kasan_save_stack(flags, true); + track->stack = kasan_save_stack(flags, STACK_DEPOT_FLAG_CAN_ALLOC); } #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS) diff --git a/mm/kasan/generic.c b/mm/kasan/generic.c index 4d837ab83f08..5d168c9afb32 100644 --- a/mm/kasan/generic.c +++ b/mm/kasan/generic.c @@ -25,6 +25,7 @@ #include <linux/sched.h> #include <linux/sched/task_stack.h> #include <linux/slab.h> +#include <linux/stackdepot.h> #include <linux/stacktrace.h> #include <linux/string.h> #include <linux/types.h> @@ -472,7 +473,7 @@ size_t kasan_metadata_size(struct kmem_cache *cache, bool in_object) sizeof(struct kasan_free_meta) : 0); } -static void __kasan_record_aux_stack(void *addr, bool can_alloc) +static void __kasan_record_aux_stack(void *addr, depot_flags_t depot_flags) { struct slab *slab = kasan_addr_to_slab(addr); struct kmem_cache *cache; @@ -489,17 +490,17 @@ static void __kasan_record_aux_stack(void *addr, bool can_alloc) return; alloc_meta->aux_stack[1] = alloc_meta->aux_stack[0]; - alloc_meta->aux_stack[0] = kasan_save_stack(0, can_alloc); + alloc_meta->aux_stack[0] = kasan_save_stack(0, depot_flags); } void kasan_record_aux_stack(void *addr) { - return __kasan_record_aux_stack(addr, true); + return __kasan_record_aux_stack(addr, STACK_DEPOT_FLAG_CAN_ALLOC); } void kasan_record_aux_stack_noalloc(void *addr) { - return __kasan_record_aux_stack(addr, false); + return __kasan_record_aux_stack(addr, 0); } void kasan_save_alloc_info(struct kmem_cache *cache, void *object, gfp_t flags) diff --git a/mm/kasan/kasan.h b/mm/kasan/kasan.h index 8b06bab5c406..b29d46b83d1f 100644 --- a/mm/kasan/kasan.h +++ b/mm/kasan/kasan.h @@ -368,7 +368,7 @@ static inline void kasan_init_cache_meta(struct kmem_cache *cache, unsigned int static inline void kasan_init_object_meta(struct kmem_cache *cache, const void *object) { } #endif -depot_stack_handle_t kasan_save_stack(gfp_t flags, bool can_alloc); +depot_stack_handle_t kasan_save_stack(gfp_t flags, depot_flags_t depot_flags); 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); diff --git a/mm/kasan/tags.c b/mm/kasan/tags.c index 7dcfe341d48e..4fd32121b0fd 100644 --- a/mm/kasan/tags.c +++ b/mm/kasan/tags.c @@ -13,6 +13,7 @@ #include <linux/memblock.h> #include <linux/memory.h> #include <linux/mm.h> +#include <linux/stackdepot.h> #include <linux/static_key.h> #include <linux/string.h> #include <linux/types.h> @@ -101,7 +102,7 @@ static void save_stack_info(struct kmem_cache *cache, void *object, struct kasan_stack_ring_entry *entry; void *old_ptr; - stack = kasan_save_stack(gfp_flags, true); + stack = kasan_save_stack(gfp_flags, STACK_DEPOT_FLAG_CAN_ALLOC); /* * Prevent save_stack_info() from modifying stack ring |