diff --git a/MAINTAINERS b/MAINTAINERS index 1dbc57efa6d0..f3f5981ced29 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -14111,6 +14111,17 @@ F: mm/ F: tools/mm/ F: tools/testing/selftests/mm/ +MEMORY MAPPING +M: Andrew Morton +R: Liam R. Howlett +R: Vlastimil Babka +R: Lorenzo Stoakes +L: linux-mm@kvack.org +S: Maintained +W: http://www.linux-mm.org +T: git git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm +F: mm/mmap.c + MEMORY TECHNOLOGY DEVICES (MTD) M: Miquel Raynal M: Richard Weinberger diff --git a/include/linux/poison.h b/include/linux/poison.h index 27a7dad17eef..1f0ee2459f2a 100644 --- a/include/linux/poison.h +++ b/include/linux/poison.h @@ -92,4 +92,7 @@ /********** VFS **********/ #define VFS_PTR_POISON ((void *)(0xF5 + POISON_POINTER_DELTA)) +/********** lib/stackdepot.c **********/ +#define STACK_DEPOT_POISON ((void *)(0xD390 + POISON_POINTER_DELTA)) + #endif diff --git a/lib/stackdepot.c b/lib/stackdepot.c index 5caa1f566553..4a7055a63d9f 100644 --- a/lib/stackdepot.c +++ b/lib/stackdepot.c @@ -22,6 +22,7 @@ #include #include #include +#include #include #include #include @@ -43,17 +44,7 @@ #define DEPOT_OFFSET_BITS (DEPOT_POOL_ORDER + PAGE_SHIFT - DEPOT_STACK_ALIGN) #define DEPOT_POOL_INDEX_BITS (DEPOT_HANDLE_BITS - DEPOT_OFFSET_BITS - \ STACK_DEPOT_EXTRA_BITS) -#if IS_ENABLED(CONFIG_KMSAN) && CONFIG_STACKDEPOT_MAX_FRAMES >= 32 -/* - * KMSAN is frequently used in fuzzing scenarios and thus saves a lot of stack - * traces. As KMSAN does not support evicting stack traces from the stack - * depot, the stack depot capacity might be reached quickly with large stack - * records. Adjust the maximum number of stack depot pools for this case. - */ -#define DEPOT_POOLS_CAP (8192 * (CONFIG_STACKDEPOT_MAX_FRAMES / 16)) -#else #define DEPOT_POOLS_CAP 8192 -#endif #define DEPOT_MAX_POOLS \ (((1LL << (DEPOT_POOL_INDEX_BITS)) < DEPOT_POOLS_CAP) ? \ (1LL << (DEPOT_POOL_INDEX_BITS)) : DEPOT_POOLS_CAP) @@ -93,9 +84,6 @@ struct stack_record { }; }; -#define DEPOT_STACK_RECORD_SIZE \ - ALIGN(sizeof(struct stack_record), 1 << DEPOT_STACK_ALIGN) - static bool stack_depot_disabled; static bool __stack_depot_early_init_requested __initdata = IS_ENABLED(CONFIG_STACKDEPOT_ALWAYS_INIT); static bool __stack_depot_early_init_passed __initdata; @@ -121,32 +109,31 @@ static void *stack_pools[DEPOT_MAX_POOLS]; static void *new_pool; /* Number of pools in stack_pools. */ static int pools_num; +/* Offset to the unused space in the currently used pool. */ +static size_t pool_offset = DEPOT_POOL_SIZE; /* Freelist of stack records within stack_pools. */ static LIST_HEAD(free_stacks); -/* - * Stack depot tries to keep an extra pool allocated even before it runs out - * of space in the currently used pool. This flag marks whether this extra pool - * needs to be allocated. It has the value 0 when either an extra pool is not - * yet allocated or if the limit on the number of pools is reached. - */ -static bool new_pool_required = true; /* The lock must be held when performing pool or freelist modifications. */ static DEFINE_RAW_SPINLOCK(pool_lock); /* Statistics counters for debugfs. */ enum depot_counter_id { - DEPOT_COUNTER_ALLOCS, - DEPOT_COUNTER_FREES, - DEPOT_COUNTER_INUSE, + DEPOT_COUNTER_REFD_ALLOCS, + DEPOT_COUNTER_REFD_FREES, + DEPOT_COUNTER_REFD_INUSE, DEPOT_COUNTER_FREELIST_SIZE, + DEPOT_COUNTER_PERSIST_COUNT, + DEPOT_COUNTER_PERSIST_BYTES, DEPOT_COUNTER_COUNT, }; static long counters[DEPOT_COUNTER_COUNT]; static const char *const counter_names[] = { - [DEPOT_COUNTER_ALLOCS] = "allocations", - [DEPOT_COUNTER_FREES] = "frees", - [DEPOT_COUNTER_INUSE] = "in_use", + [DEPOT_COUNTER_REFD_ALLOCS] = "refcounted_allocations", + [DEPOT_COUNTER_REFD_FREES] = "refcounted_frees", + [DEPOT_COUNTER_REFD_INUSE] = "refcounted_in_use", [DEPOT_COUNTER_FREELIST_SIZE] = "freelist_size", + [DEPOT_COUNTER_PERSIST_COUNT] = "persistent_count", + [DEPOT_COUNTER_PERSIST_BYTES] = "persistent_bytes", }; static_assert(ARRAY_SIZE(counter_names) == DEPOT_COUNTER_COUNT); @@ -294,48 +281,52 @@ out_unlock: EXPORT_SYMBOL_GPL(stack_depot_init); /* - * Initializes new stack depot @pool, release all its entries to the freelist, - * and update the list of pools. + * Initializes new stack pool, and updates the list of pools. */ -static void depot_init_pool(void *pool) +static bool depot_init_pool(void **prealloc) { - int offset; - lockdep_assert_held(&pool_lock); - /* Initialize handles and link stack records into the freelist. */ - for (offset = 0; offset <= DEPOT_POOL_SIZE - DEPOT_STACK_RECORD_SIZE; - offset += DEPOT_STACK_RECORD_SIZE) { - struct stack_record *stack = pool + offset; - - stack->handle.pool_index = pools_num; - stack->handle.offset = offset >> DEPOT_STACK_ALIGN; - stack->handle.extra = 0; - - /* - * Stack traces of size 0 are never saved, and we can simply use - * the size field as an indicator if this is a new unused stack - * record in the freelist. - */ - stack->size = 0; - - INIT_LIST_HEAD(&stack->hash_list); - /* - * Add to the freelist front to prioritize never-used entries: - * required in case there are entries in the freelist, but their - * RCU cookie still belongs to the current RCU grace period - * (there can still be concurrent readers). - */ - list_add(&stack->free_list, &free_stacks); - counters[DEPOT_COUNTER_FREELIST_SIZE]++; + if (unlikely(pools_num >= DEPOT_MAX_POOLS)) { + /* Bail out if we reached the pool limit. */ + WARN_ON_ONCE(pools_num > DEPOT_MAX_POOLS); /* should never happen */ + WARN_ON_ONCE(!new_pool); /* to avoid unnecessary pre-allocation */ + WARN_ONCE(1, "Stack depot reached limit capacity"); + return false; } + if (!new_pool && *prealloc) { + /* We have preallocated memory, use it. */ + WRITE_ONCE(new_pool, *prealloc); + *prealloc = NULL; + } + + if (!new_pool) + return false; /* new_pool and *prealloc are NULL */ + /* Save reference to the pool to be used by depot_fetch_stack(). */ - stack_pools[pools_num] = pool; + stack_pools[pools_num] = new_pool; + + /* + * Stack depot tries to keep an extra pool allocated even before it runs + * out of space in the currently used pool. + * + * To indicate that a new preallocation is needed new_pool is reset to + * NULL; do not reset to NULL if we have reached the maximum number of + * pools. + */ + if (pools_num < DEPOT_MAX_POOLS) + WRITE_ONCE(new_pool, NULL); + else + WRITE_ONCE(new_pool, STACK_DEPOT_POISON); /* Pairs with concurrent READ_ONCE() in depot_fetch_stack(). */ WRITE_ONCE(pools_num, pools_num + 1); ASSERT_EXCLUSIVE_WRITER(pools_num); + + pool_offset = 0; + + return true; } /* Keeps the preallocated memory to be used for a new stack depot pool. */ @@ -347,63 +338,51 @@ static void depot_keep_new_pool(void **prealloc) * If a new pool is already saved or the maximum number of * pools is reached, do not use the preallocated memory. */ - if (!new_pool_required) + if (new_pool) return; - /* - * Use the preallocated memory for the new pool - * as long as we do not exceed the maximum number of pools. - */ - if (pools_num < DEPOT_MAX_POOLS) { - new_pool = *prealloc; - *prealloc = NULL; - } - - /* - * At this point, either a new pool is kept or the maximum - * number of pools is reached. In either case, take note that - * keeping another pool is not required. - */ - WRITE_ONCE(new_pool_required, false); + WRITE_ONCE(new_pool, *prealloc); + *prealloc = NULL; } /* - * Try to initialize a new stack depot pool from either a previous or the - * current pre-allocation, and release all its entries to the freelist. + * Try to initialize a new stack record from the current pool, a cached pool, or + * the current pre-allocation. */ -static bool depot_try_init_pool(void **prealloc) +static struct stack_record *depot_pop_free_pool(void **prealloc, size_t size) { + struct stack_record *stack; + void *current_pool; + u32 pool_index; + lockdep_assert_held(&pool_lock); - /* Check if we have a new pool saved and use it. */ - if (new_pool) { - depot_init_pool(new_pool); - new_pool = NULL; - - /* Take note that we might need a new new_pool. */ - if (pools_num < DEPOT_MAX_POOLS) - WRITE_ONCE(new_pool_required, true); - - return true; + if (pool_offset + size > DEPOT_POOL_SIZE) { + if (!depot_init_pool(prealloc)) + return NULL; } - /* Bail out if we reached the pool limit. */ - if (unlikely(pools_num >= DEPOT_MAX_POOLS)) { - WARN_ONCE(1, "Stack depot reached limit capacity"); - return false; - } + if (WARN_ON_ONCE(pools_num < 1)) + return NULL; + pool_index = pools_num - 1; + current_pool = stack_pools[pool_index]; + if (WARN_ON_ONCE(!current_pool)) + return NULL; - /* Check if we have preallocated memory and use it. */ - if (*prealloc) { - depot_init_pool(*prealloc); - *prealloc = NULL; - return true; - } + stack = current_pool + pool_offset; - return false; + /* Pre-initialize handle once. */ + stack->handle.pool_index = pool_index; + stack->handle.offset = pool_offset >> DEPOT_STACK_ALIGN; + stack->handle.extra = 0; + INIT_LIST_HEAD(&stack->hash_list); + + pool_offset += size; + + return stack; } -/* Try to find next free usable entry. */ +/* Try to find next free usable entry from the freelist. */ static struct stack_record *depot_pop_free(void) { struct stack_record *stack; @@ -420,7 +399,7 @@ static struct stack_record *depot_pop_free(void) * check the first entry. */ stack = list_first_entry(&free_stacks, struct stack_record, free_list); - if (stack->size && !poll_state_synchronize_rcu(stack->rcu_state)) + if (!poll_state_synchronize_rcu(stack->rcu_state)) return NULL; list_del(&stack->free_list); @@ -429,48 +408,73 @@ static struct stack_record *depot_pop_free(void) return stack; } +static inline size_t depot_stack_record_size(struct stack_record *s, unsigned int nr_entries) +{ + const size_t used = flex_array_size(s, entries, nr_entries); + const size_t unused = sizeof(s->entries) - used; + + WARN_ON_ONCE(sizeof(s->entries) < used); + + return ALIGN(sizeof(struct stack_record) - unused, 1 << DEPOT_STACK_ALIGN); +} + /* Allocates a new stack in a stack depot pool. */ static struct stack_record * -depot_alloc_stack(unsigned long *entries, int size, u32 hash, void **prealloc) +depot_alloc_stack(unsigned long *entries, unsigned int nr_entries, u32 hash, depot_flags_t flags, void **prealloc) { - struct stack_record *stack; + struct stack_record *stack = NULL; + size_t record_size; lockdep_assert_held(&pool_lock); /* This should already be checked by public API entry points. */ - if (WARN_ON_ONCE(!size)) + if (WARN_ON_ONCE(!nr_entries)) return NULL; - /* Check if we have a stack record to save the stack trace. */ - stack = depot_pop_free(); - if (!stack) { - /* No usable entries on the freelist - try to refill the freelist. */ - if (!depot_try_init_pool(prealloc)) - return NULL; + /* Limit number of saved frames to CONFIG_STACKDEPOT_MAX_FRAMES. */ + if (nr_entries > CONFIG_STACKDEPOT_MAX_FRAMES) + nr_entries = CONFIG_STACKDEPOT_MAX_FRAMES; + + if (flags & STACK_DEPOT_FLAG_GET) { + /* + * Evictable entries have to allocate the max. size so they may + * safely be re-used by differently sized allocations. + */ + record_size = depot_stack_record_size(stack, CONFIG_STACKDEPOT_MAX_FRAMES); stack = depot_pop_free(); - if (WARN_ON(!stack)) + } else { + record_size = depot_stack_record_size(stack, nr_entries); + } + + if (!stack) { + stack = depot_pop_free_pool(prealloc, record_size); + if (!stack) return NULL; } - /* Limit number of saved frames to CONFIG_STACKDEPOT_MAX_FRAMES. */ - if (size > CONFIG_STACKDEPOT_MAX_FRAMES) - size = CONFIG_STACKDEPOT_MAX_FRAMES; - /* Save the stack trace. */ stack->hash = hash; - stack->size = size; - /* stack->handle is already filled in by depot_init_pool(). */ - refcount_set(&stack->count, 1); - memcpy(stack->entries, entries, flex_array_size(stack, entries, size)); + stack->size = nr_entries; + /* stack->handle is already filled in by depot_pop_free_pool(). */ + memcpy(stack->entries, entries, flex_array_size(stack, entries, nr_entries)); + + if (flags & STACK_DEPOT_FLAG_GET) { + refcount_set(&stack->count, 1); + counters[DEPOT_COUNTER_REFD_ALLOCS]++; + counters[DEPOT_COUNTER_REFD_INUSE]++; + } else { + /* Warn on attempts to switch to refcounting this entry. */ + refcount_set(&stack->count, REFCOUNT_SATURATED); + counters[DEPOT_COUNTER_PERSIST_COUNT]++; + counters[DEPOT_COUNTER_PERSIST_BYTES] += record_size; + } /* * Let KMSAN know the stored stack record is initialized. This shall * prevent false positive reports if instrumented code accesses it. */ - kmsan_unpoison_memory(stack, DEPOT_STACK_RECORD_SIZE); + kmsan_unpoison_memory(stack, record_size); - counters[DEPOT_COUNTER_ALLOCS]++; - counters[DEPOT_COUNTER_INUSE]++; return stack; } @@ -538,8 +542,8 @@ static void depot_free_stack(struct stack_record *stack) list_add_tail(&stack->free_list, &free_stacks); counters[DEPOT_COUNTER_FREELIST_SIZE]++; - counters[DEPOT_COUNTER_FREES]++; - counters[DEPOT_COUNTER_INUSE]--; + counters[DEPOT_COUNTER_REFD_FREES]++; + counters[DEPOT_COUNTER_REFD_INUSE]--; printk_deferred_exit(); raw_spin_unlock_irqrestore(&pool_lock, flags); @@ -660,7 +664,7 @@ depot_stack_handle_t stack_depot_save_flags(unsigned long *entries, * Allocate memory for a new pool if required now: * we won't be able to do that under the lock. */ - if (unlikely(can_alloc && READ_ONCE(new_pool_required))) { + if (unlikely(can_alloc && !READ_ONCE(new_pool))) { /* * Zero out zone modifiers, as we don't have specific zone * requirements. Keep the flags related to allocation in atomic @@ -681,7 +685,7 @@ depot_stack_handle_t stack_depot_save_flags(unsigned long *entries, found = find_stack(bucket, entries, nr_entries, hash, depot_flags); if (!found) { struct stack_record *new = - depot_alloc_stack(entries, nr_entries, hash, &prealloc); + depot_alloc_stack(entries, nr_entries, hash, depot_flags, &prealloc); if (new) { /* diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c index 5662e29fe253..65c19025da3d 100644 --- a/mm/debug_vm_pgtable.c +++ b/mm/debug_vm_pgtable.c @@ -362,6 +362,12 @@ static void __init pud_advanced_tests(struct pgtable_debug_args *args) vaddr &= HPAGE_PUD_MASK; pud = pfn_pud(args->pud_pfn, args->page_prot); + /* + * Some architectures have debug checks to make sure + * huge pud mapping are only found with devmap entries + * For now test with only devmap entries. + */ + pud = pud_mkdevmap(pud); set_pud_at(args->mm, vaddr, args->pudp, pud); flush_dcache_page(page); pudp_set_wrprotect(args->mm, vaddr, args->pudp); @@ -374,6 +380,7 @@ static void __init pud_advanced_tests(struct pgtable_debug_args *args) WARN_ON(!pud_none(pud)); #endif /* __PAGETABLE_PMD_FOLDED */ pud = pfn_pud(args->pud_pfn, args->page_prot); + pud = pud_mkdevmap(pud); pud = pud_wrprotect(pud); pud = pud_mkclean(pud); set_pud_at(args->mm, vaddr, args->pudp, pud); @@ -391,6 +398,7 @@ static void __init pud_advanced_tests(struct pgtable_debug_args *args) #endif /* __PAGETABLE_PMD_FOLDED */ pud = pfn_pud(args->pud_pfn, args->page_prot); + pud = pud_mkdevmap(pud); pud = pud_mkyoung(pud); set_pud_at(args->mm, vaddr, args->pudp, pud); flush_dcache_page(page); diff --git a/mm/filemap.c b/mm/filemap.c index 142864338ca4..b7a21551fbc7 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -4111,28 +4111,40 @@ static void filemap_cachestat(struct address_space *mapping, rcu_read_lock(); xas_for_each(&xas, folio, last_index) { + int order; unsigned long nr_pages; pgoff_t folio_first_index, folio_last_index; + /* + * Don't deref the folio. It is not pinned, and might + * get freed (and reused) underneath us. + * + * We *could* pin it, but that would be expensive for + * what should be a fast and lightweight syscall. + * + * Instead, derive all information of interest from + * the rcu-protected xarray. + */ + if (xas_retry(&xas, folio)) continue; + order = xa_get_order(xas.xa, xas.xa_index); + nr_pages = 1 << order; + folio_first_index = round_down(xas.xa_index, 1 << order); + folio_last_index = folio_first_index + nr_pages - 1; + + /* Folios might straddle the range boundaries, only count covered pages */ + if (folio_first_index < first_index) + nr_pages -= first_index - folio_first_index; + + if (folio_last_index > last_index) + nr_pages -= folio_last_index - last_index; + if (xa_is_value(folio)) { /* page is evicted */ void *shadow = (void *)folio; bool workingset; /* not used */ - int order = xa_get_order(xas.xa, xas.xa_index); - - nr_pages = 1 << order; - folio_first_index = round_down(xas.xa_index, 1 << order); - folio_last_index = folio_first_index + nr_pages - 1; - - /* Folios might straddle the range boundaries, only count covered pages */ - if (folio_first_index < first_index) - nr_pages -= first_index - folio_first_index; - - if (folio_last_index > last_index) - nr_pages -= folio_last_index - last_index; cs->nr_evicted += nr_pages; @@ -4150,24 +4162,13 @@ static void filemap_cachestat(struct address_space *mapping, goto resched; } - nr_pages = folio_nr_pages(folio); - folio_first_index = folio_pgoff(folio); - folio_last_index = folio_first_index + nr_pages - 1; - - /* Folios might straddle the range boundaries, only count covered pages */ - if (folio_first_index < first_index) - nr_pages -= first_index - folio_first_index; - - if (folio_last_index > last_index) - nr_pages -= folio_last_index - last_index; - /* page is in cache */ cs->nr_cache += nr_pages; - if (folio_test_dirty(folio)) + if (xas_get_mark(&xas, PAGECACHE_TAG_DIRTY)) cs->nr_dirty += nr_pages; - if (folio_test_writeback(folio)) + if (xas_get_mark(&xas, PAGECACHE_TAG_WRITEBACK)) cs->nr_writeback += nr_pages; resched: diff --git a/mm/kasan/common.c b/mm/kasan/common.c index f2747ed30da0..e7c9a4dc89f8 100644 --- a/mm/kasan/common.c +++ b/mm/kasan/common.c @@ -65,8 +65,7 @@ void kasan_save_track(struct kasan_track *track, gfp_t flags) { depot_stack_handle_t stack; - stack = kasan_save_stack(flags, - STACK_DEPOT_FLAG_CAN_ALLOC | STACK_DEPOT_FLAG_GET); + stack = kasan_save_stack(flags, STACK_DEPOT_FLAG_CAN_ALLOC); kasan_set_track(track, stack); } @@ -266,10 +265,9 @@ bool __kasan_slab_free(struct kmem_cache *cache, void *object, return true; /* - * If the object is not put into quarantine, it will likely be quickly - * reallocated. Thus, release its metadata now. + * Note: Keep per-object metadata to allow KASAN print stack traces for + * use-after-free-before-realloc bugs. */ - kasan_release_object_meta(cache, object); /* Let slab put the object onto the freelist. */ return false; diff --git a/mm/kasan/generic.c b/mm/kasan/generic.c index 032bf3e98c24..1900f8576034 100644 --- a/mm/kasan/generic.c +++ b/mm/kasan/generic.c @@ -485,16 +485,6 @@ void kasan_init_object_meta(struct kmem_cache *cache, const void *object) if (alloc_meta) { /* Zero out alloc meta to mark it as invalid. */ __memset(alloc_meta, 0, sizeof(*alloc_meta)); - - /* - * Prepare the lock for saving auxiliary stack traces. - * Temporarily disable KASAN bug reporting to allow instrumented - * raw_spin_lock_init to access aux_lock, which resides inside - * of a redzone. - */ - kasan_disable_current(); - raw_spin_lock_init(&alloc_meta->aux_lock); - kasan_enable_current(); } /* @@ -506,18 +496,8 @@ void kasan_init_object_meta(struct kmem_cache *cache, const void *object) static void release_alloc_meta(struct kasan_alloc_meta *meta) { - /* Evict the stack traces from stack depot. */ - stack_depot_put(meta->alloc_track.stack); - stack_depot_put(meta->aux_stack[0]); - stack_depot_put(meta->aux_stack[1]); - - /* - * Zero out alloc meta to mark it as invalid but keep aux_lock - * initialized to avoid having to reinitialize it when another object - * is allocated in the same slot. - */ - __memset(&meta->alloc_track, 0, sizeof(meta->alloc_track)); - __memset(meta->aux_stack, 0, sizeof(meta->aux_stack)); + /* Zero out alloc meta to mark it as invalid. */ + __memset(meta, 0, sizeof(*meta)); } static void release_free_meta(const void *object, struct kasan_free_meta *meta) @@ -529,27 +509,10 @@ static void release_free_meta(const void *object, struct kasan_free_meta *meta) if (*(u8 *)kasan_mem_to_shadow(object) != KASAN_SLAB_FREE_META) return; - /* Evict the stack trace from the stack depot. */ - stack_depot_put(meta->free_track.stack); - /* Mark free meta as invalid. */ *(u8 *)kasan_mem_to_shadow(object) = KASAN_SLAB_FREE; } -void kasan_release_object_meta(struct kmem_cache *cache, const void *object) -{ - struct kasan_alloc_meta *alloc_meta; - struct kasan_free_meta *free_meta; - - alloc_meta = kasan_get_alloc_meta(cache, object); - if (alloc_meta) - release_alloc_meta(alloc_meta); - - free_meta = kasan_get_free_meta(cache, object); - if (free_meta) - release_free_meta(object, free_meta); -} - size_t kasan_metadata_size(struct kmem_cache *cache, bool in_object) { struct kasan_cache *info = &cache->kasan_info; @@ -574,8 +537,6 @@ static void __kasan_record_aux_stack(void *addr, depot_flags_t depot_flags) struct kmem_cache *cache; struct kasan_alloc_meta *alloc_meta; void *object; - depot_stack_handle_t new_handle, old_handle; - unsigned long flags; if (is_kfence_address(addr) || !slab) return; @@ -586,33 +547,18 @@ static void __kasan_record_aux_stack(void *addr, depot_flags_t depot_flags) if (!alloc_meta) return; - new_handle = kasan_save_stack(0, depot_flags); - - /* - * Temporarily disable KASAN bug reporting to allow instrumented - * spinlock functions to access aux_lock, which resides inside of a - * redzone. - */ - kasan_disable_current(); - raw_spin_lock_irqsave(&alloc_meta->aux_lock, flags); - old_handle = alloc_meta->aux_stack[1]; alloc_meta->aux_stack[1] = alloc_meta->aux_stack[0]; - alloc_meta->aux_stack[0] = new_handle; - raw_spin_unlock_irqrestore(&alloc_meta->aux_lock, flags); - kasan_enable_current(); - - stack_depot_put(old_handle); + alloc_meta->aux_stack[0] = kasan_save_stack(0, depot_flags); } void kasan_record_aux_stack(void *addr) { - return __kasan_record_aux_stack(addr, - STACK_DEPOT_FLAG_CAN_ALLOC | STACK_DEPOT_FLAG_GET); + 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, STACK_DEPOT_FLAG_GET); + return __kasan_record_aux_stack(addr, 0); } void kasan_save_alloc_info(struct kmem_cache *cache, void *object, gfp_t flags) @@ -623,7 +569,7 @@ void kasan_save_alloc_info(struct kmem_cache *cache, void *object, gfp_t flags) if (!alloc_meta) return; - /* Evict previous stack traces (might exist for krealloc or mempool). */ + /* Invalidate previous stack traces (might exist for krealloc or mempool). */ release_alloc_meta(alloc_meta); kasan_save_track(&alloc_meta->alloc_track, flags); @@ -637,7 +583,7 @@ void kasan_save_free_info(struct kmem_cache *cache, void *object) if (!free_meta) return; - /* Evict previous stack trace (might exist for mempool). */ + /* Invalidate previous stack trace (might exist for mempool). */ release_free_meta(object, free_meta); kasan_save_track(&free_meta->free_track, 0); diff --git a/mm/kasan/kasan.h b/mm/kasan/kasan.h index d0f172f2b978..fb2b9ac0659a 100644 --- a/mm/kasan/kasan.h +++ b/mm/kasan/kasan.h @@ -6,7 +6,6 @@ #include #include #include -#include #include #if defined(CONFIG_KASAN_SW_TAGS) || defined(CONFIG_KASAN_HW_TAGS) @@ -265,13 +264,6 @@ struct kasan_global { struct kasan_alloc_meta { struct kasan_track alloc_track; /* Free track is stored in kasan_free_meta. */ - /* - * aux_lock protects aux_stack from accesses from concurrent - * kasan_record_aux_stack calls. It is a raw spinlock to avoid sleeping - * on RT kernels, as kasan_record_aux_stack_noalloc can be called from - * non-sleepable contexts. - */ - raw_spinlock_t aux_lock; depot_stack_handle_t aux_stack[2]; }; @@ -398,10 +390,8 @@ struct kasan_alloc_meta *kasan_get_alloc_meta(struct kmem_cache *cache, struct kasan_free_meta *kasan_get_free_meta(struct kmem_cache *cache, const void *object); void kasan_init_object_meta(struct kmem_cache *cache, const void *object); -void kasan_release_object_meta(struct kmem_cache *cache, const void *object); #else static inline void kasan_init_object_meta(struct kmem_cache *cache, const void *object) { } -static inline void kasan_release_object_meta(struct kmem_cache *cache, const void *object) { } #endif depot_stack_handle_t kasan_save_stack(gfp_t flags, depot_flags_t depot_flags); diff --git a/mm/kasan/quarantine.c b/mm/kasan/quarantine.c index 3ba02efb952a..6958aa713c67 100644 --- a/mm/kasan/quarantine.c +++ b/mm/kasan/quarantine.c @@ -145,7 +145,10 @@ static void qlink_free(struct qlist_node *qlink, struct kmem_cache *cache) void *object = qlink_to_object(qlink, cache); struct kasan_free_meta *free_meta = kasan_get_free_meta(cache, object); - kasan_release_object_meta(cache, object); + /* + * Note: Keep per-object metadata to allow KASAN print stack traces for + * use-after-free-before-realloc bugs. + */ /* * If init_on_free is enabled and KASAN's free metadata is stored in diff --git a/mm/migrate.c b/mm/migrate.c index 05d6ca437321..73a052a382f1 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -2522,6 +2522,14 @@ static int numamigrate_isolate_folio(pg_data_t *pgdat, struct folio *folio) if (managed_zone(pgdat->node_zones + z)) break; } + + /* + * If there are no managed zones, it should not proceed + * further. + */ + if (z < 0) + return 0; + wakeup_kswapd(pgdat->node_zones + z, 0, folio_order(folio), ZONE_MOVABLE); return 0;