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authorLinus Torvalds <torvalds@linux-foundation.org>2024-01-09 11:18:47 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2024-01-09 11:18:47 -0800
commitfb46e22a9e3863e08aef8815df9f17d0f4b9aede (patch)
tree83e052911fa8d8d90bcf9de2796e17e19040613f /mm/kasan/kasan.h
parentd30e51aa7b1f6fa7dd78d4598d1e4c047fcc3fb9 (diff)
parent5e0a760b44417f7cadd79de2204d6247109558a0 (diff)
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Merge tag 'mm-stable-2024-01-08-15-31' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull MM updates from Andrew Morton: "Many singleton patches against the MM code. The patch series which are included in this merge do the following: - Peng Zhang has done some mapletree maintainance work in the series 'maple_tree: add mt_free_one() and mt_attr() helpers' 'Some cleanups of maple tree' - In the series 'mm: use memmap_on_memory semantics for dax/kmem' Vishal Verma has altered the interworking between memory-hotplug and dax/kmem so that newly added 'device memory' can more easily have its memmap placed within that newly added memory. - Matthew Wilcox continues folio-related work (including a few fixes) in the patch series 'Add folio_zero_tail() and folio_fill_tail()' 'Make folio_start_writeback return void' 'Fix fault handler's handling of poisoned tail pages' 'Convert aops->error_remove_page to ->error_remove_folio' 'Finish two folio conversions' 'More swap folio conversions' - Kefeng Wang has also contributed folio-related work in the series 'mm: cleanup and use more folio in page fault' - Jim Cromie has improved the kmemleak reporting output in the series 'tweak kmemleak report format'. - In the series 'stackdepot: allow evicting stack traces' Andrey Konovalov to permits clients (in this case KASAN) to cause eviction of no longer needed stack traces. - Charan Teja Kalla has fixed some accounting issues in the page allocator's atomic reserve calculations in the series 'mm: page_alloc: fixes for high atomic reserve caluculations'. - Dmitry Rokosov has added to the samples/ dorectory some sample code for a userspace memcg event listener application. See the series 'samples: introduce cgroup events listeners'. - Some mapletree maintanance work from Liam Howlett in the series 'maple_tree: iterator state changes'. - Nhat Pham has improved zswap's approach to writeback in the series 'workload-specific and memory pressure-driven zswap writeback'. - DAMON/DAMOS feature and maintenance work from SeongJae Park in the series 'mm/damon: let users feed and tame/auto-tune DAMOS' 'selftests/damon: add Python-written DAMON functionality tests' 'mm/damon: misc updates for 6.8' - Yosry Ahmed has improved memcg's stats flushing in the series 'mm: memcg: subtree stats flushing and thresholds'. - In the series 'Multi-size THP for anonymous memory' Ryan Roberts has added a runtime opt-in feature to transparent hugepages which improves performance by allocating larger chunks of memory during anonymous page faults. - Matthew Wilcox has also contributed some cleanup and maintenance work against eh buffer_head code int he series 'More buffer_head cleanups'. - Suren Baghdasaryan has done work on Andrea Arcangeli's series 'userfaultfd move option'. UFFDIO_MOVE permits userspace heap compaction algorithms to move userspace's pages around rather than UFFDIO_COPY'a alloc/copy/free. - Stefan Roesch has developed a 'KSM Advisor', in the series 'mm/ksm: Add ksm advisor'. This is a governor which tunes KSM's scanning aggressiveness in response to userspace's current needs. - Chengming Zhou has optimized zswap's temporary working memory use in the series 'mm/zswap: dstmem reuse optimizations and cleanups'. - Matthew Wilcox has performed some maintenance work on the writeback code, both code and within filesystems. The series is 'Clean up the writeback paths'. - Andrey Konovalov has optimized KASAN's handling of alloc and free stack traces for secondary-level allocators, in the series 'kasan: save mempool stack traces'. - Andrey also performed some KASAN maintenance work in the series 'kasan: assorted clean-ups'. - David Hildenbrand has gone to town on the rmap code. Cleanups, more pte batching, folio conversions and more. See the series 'mm/rmap: interface overhaul'. - Kinsey Ho has contributed some maintenance work on the MGLRU code in the series 'mm/mglru: Kconfig cleanup'. - Matthew Wilcox has contributed lruvec page accounting code cleanups in the series 'Remove some lruvec page accounting functions'" * tag 'mm-stable-2024-01-08-15-31' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (361 commits) mm, treewide: rename MAX_ORDER to MAX_PAGE_ORDER mm, treewide: introduce NR_PAGE_ORDERS selftests/mm: add separate UFFDIO_MOVE test for PMD splitting selftests/mm: skip test if application doesn't has root privileges selftests/mm: conform test to TAP format output selftests: mm: hugepage-mmap: conform to TAP format output selftests/mm: gup_test: conform test to TAP format output mm/selftests: hugepage-mremap: conform test to TAP format output mm/vmstat: move pgdemote_* out of CONFIG_NUMA_BALANCING mm: zsmalloc: return -ENOSPC rather than -EINVAL in zs_malloc while size is too large mm/memcontrol: remove __mod_lruvec_page_state() mm/khugepaged: use a folio more in collapse_file() slub: use a folio in __kmalloc_large_node slub: use folio APIs in free_large_kmalloc() slub: use alloc_pages_node() in alloc_slab_page() mm: remove inc/dec lruvec page state functions mm: ratelimit stat flush from workingset shrinker kasan: stop leaking stack trace handles mm/mglru: remove CONFIG_TRANSPARENT_HUGEPAGE mm/mglru: add dummy pmd_dirty() ...
Diffstat (limited to 'mm/kasan/kasan.h')
-rw-r--r--mm/kasan/kasan.h93
1 files changed, 58 insertions, 35 deletions
diff --git a/mm/kasan/kasan.h b/mm/kasan/kasan.h
index eef50233640a..d0f172f2b978 100644
--- a/mm/kasan/kasan.h
+++ b/mm/kasan/kasan.h
@@ -6,6 +6,7 @@
#include <linux/kasan.h>
#include <linux/kasan-tags.h>
#include <linux/kfence.h>
+#include <linux/spinlock.h>
#include <linux/stackdepot.h>
#if defined(CONFIG_KASAN_SW_TAGS) || defined(CONFIG_KASAN_HW_TAGS)
@@ -48,6 +49,7 @@ DECLARE_PER_CPU(long, kasan_page_alloc_skip);
static inline bool kasan_vmalloc_enabled(void)
{
+ /* Static branch is never enabled with CONFIG_KASAN_VMALLOC disabled. */
return static_branch_likely(&kasan_flag_vmalloc);
}
@@ -81,6 +83,11 @@ static inline bool kasan_sample_page_alloc(unsigned int order)
#else /* CONFIG_KASAN_HW_TAGS */
+static inline bool kasan_vmalloc_enabled(void)
+{
+ return IS_ENABLED(CONFIG_KASAN_VMALLOC);
+}
+
static inline bool kasan_async_fault_possible(void)
{
return false;
@@ -100,21 +107,21 @@ static inline bool kasan_sample_page_alloc(unsigned int order)
#ifdef CONFIG_KASAN_GENERIC
-/* Generic KASAN uses per-object metadata to store stack traces. */
+/*
+ * Generic KASAN uses per-object metadata to store alloc and free stack traces
+ * and the quarantine link.
+ */
static inline bool kasan_requires_meta(void)
{
- /*
- * Technically, Generic KASAN always collects stack traces right now.
- * However, let's use kasan_stack_collection_enabled() in case the
- * kasan.stacktrace command-line argument is changed to affect
- * Generic KASAN.
- */
- return kasan_stack_collection_enabled();
+ return true;
}
#else /* CONFIG_KASAN_GENERIC */
-/* Tag-based KASAN modes do not use per-object metadata. */
+/*
+ * Tag-based KASAN modes do not use per-object metadata: they use the stack
+ * ring to store alloc and free stack traces and do not use qurantine.
+ */
static inline bool kasan_requires_meta(void)
{
return false;
@@ -149,7 +156,7 @@ static inline bool kasan_requires_meta(void)
#ifdef CONFIG_KASAN_GENERIC
-#define KASAN_SLAB_FREETRACK 0xFA /* freed slab object with free track */
+#define KASAN_SLAB_FREE_META 0xFA /* freed slab object with free meta */
#define KASAN_GLOBAL_REDZONE 0xF9 /* redzone for global variable */
/* Stack redzone shadow values. Compiler ABI, do not change. */
@@ -187,6 +194,10 @@ static inline bool kasan_requires_meta(void)
struct kasan_track {
u32 pid;
depot_stack_handle_t stack;
+#ifdef CONFIG_KASAN_EXTRA_INFO
+ u64 cpu:20;
+ u64 timestamp:44;
+#endif /* CONFIG_KASAN_EXTRA_INFO */
};
enum kasan_report_type {
@@ -242,9 +253,25 @@ struct kasan_global {
#ifdef CONFIG_KASAN_GENERIC
+/*
+ * Alloc meta contains the allocation-related information about a slab object.
+ * Alloc meta is saved when an object is allocated and is kept until either the
+ * object returns to the slab freelist (leaves quarantine for quarantined
+ * objects or gets freed for the non-quarantined ones) or reallocated via
+ * krealloc or through a mempool.
+ * Alloc meta is stored inside of the object's redzone.
+ * Alloc meta is considered valid whenever it contains non-zero data.
+ */
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];
};
@@ -260,8 +287,12 @@ struct qlist_node {
#define KASAN_NO_FREE_META INT_MAX
/*
- * Free meta is only used by Generic mode while the object is in quarantine.
- * After that, slab allocator stores the freelist pointer in the object.
+ * Free meta contains the freeing-related information about a slab object.
+ * Free meta is only kept for quarantined objects and for mempool objects until
+ * the object gets allocated again.
+ * Free meta is stored within the object's memory.
+ * Free meta is considered valid whenever the value of the shadow byte that
+ * corresponds to the first 8 bytes of the object is KASAN_SLAB_FREE_META.
*/
struct kasan_free_meta {
struct qlist_node quarantine_link;
@@ -275,8 +306,7 @@ struct kasan_free_meta {
struct kasan_stack_ring_entry {
void *ptr;
size_t size;
- u32 pid;
- depot_stack_handle_t stack;
+ struct kasan_track track;
bool is_free;
};
@@ -291,6 +321,12 @@ struct kasan_stack_ring {
#if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
+static __always_inline bool addr_in_shadow(const void *addr)
+{
+ return addr >= (void *)KASAN_SHADOW_START &&
+ addr < (void *)KASAN_SHADOW_END;
+}
+
#ifndef kasan_shadow_to_mem
static inline const void *kasan_shadow_to_mem(const void *shadow_addr)
{
@@ -357,19 +393,20 @@ void kasan_report_invalid_free(void *object, unsigned long ip, enum kasan_report
struct slab *kasan_addr_to_slab(const void *addr);
#ifdef CONFIG_KASAN_GENERIC
-void kasan_init_cache_meta(struct kmem_cache *cache, unsigned int *size);
-void kasan_init_object_meta(struct kmem_cache *cache, const void *object);
struct kasan_alloc_meta *kasan_get_alloc_meta(struct kmem_cache *cache,
const void *object);
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_cache_meta(struct kmem_cache *cache, unsigned int *size) { }
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, bool can_alloc);
-void kasan_set_track(struct kasan_track *track, gfp_t flags);
+depot_stack_handle_t kasan_save_stack(gfp_t flags, depot_flags_t depot_flags);
+void kasan_set_track(struct kasan_track *track, depot_stack_handle_t stack);
+void kasan_save_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);
@@ -443,35 +480,23 @@ static inline u8 kasan_random_tag(void) { return 0; }
static inline void kasan_poison(const void *addr, size_t size, u8 value, bool init)
{
- addr = kasan_reset_tag(addr);
-
- /* Skip KFENCE memory if called explicitly outside of sl*b. */
- if (is_kfence_address(addr))
- return;
-
if (WARN_ON((unsigned long)addr & KASAN_GRANULE_MASK))
return;
if (WARN_ON(size & KASAN_GRANULE_MASK))
return;
- hw_set_mem_tag_range((void *)addr, size, value, init);
+ hw_set_mem_tag_range(kasan_reset_tag(addr), size, value, init);
}
static inline void kasan_unpoison(const void *addr, size_t size, bool init)
{
u8 tag = get_tag(addr);
- addr = kasan_reset_tag(addr);
-
- /* Skip KFENCE memory if called explicitly outside of sl*b. */
- if (is_kfence_address(addr))
- return;
-
if (WARN_ON((unsigned long)addr & KASAN_GRANULE_MASK))
return;
size = round_up(size, KASAN_GRANULE_SIZE);
- hw_set_mem_tag_range((void *)addr, size, tag, init);
+ hw_set_mem_tag_range(kasan_reset_tag(addr), size, tag, init);
}
static inline bool kasan_byte_accessible(const void *addr)
@@ -490,8 +515,6 @@ static inline bool kasan_byte_accessible(const void *addr)
* @size - range size, must be aligned to KASAN_GRANULE_SIZE
* @value - value that's written to metadata for the range
* @init - whether to initialize the memory range (only for hardware tag-based)
- *
- * The size gets aligned to KASAN_GRANULE_SIZE before marking the range.
*/
void kasan_poison(const void *addr, size_t size, u8 value, bool init);