diff options
| -rw-r--r-- | mm/slub.c | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/mm/slub.c b/mm/slub.c index 6833b73ef6b3..37555ad8894d 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -20,6 +20,7 @@ #include <linux/proc_fs.h> #include <linux/notifier.h> #include <linux/seq_file.h> +#include <linux/kasan.h> #include <linux/kmemcheck.h> #include <linux/cpu.h> #include <linux/cpuset.h> @@ -468,12 +469,30 @@ static char *slub_debug_slabs; static int disable_higher_order_debug; /* + * slub is about to manipulate internal object metadata. This memory lies + * outside the range of the allocated object, so accessing it would normally + * be reported by kasan as a bounds error. metadata_access_enable() is used + * to tell kasan that these accesses are OK. + */ +static inline void metadata_access_enable(void) +{ + kasan_disable_current(); +} + +static inline void metadata_access_disable(void) +{ + kasan_enable_current(); +} + +/* * Object debugging */ static void print_section(char *text, u8 *addr, unsigned int length) { + metadata_access_enable(); print_hex_dump(KERN_ERR, text, DUMP_PREFIX_ADDRESS, 16, 1, addr, length, 1); + metadata_access_disable(); } static struct track *get_track(struct kmem_cache *s, void *object, @@ -503,7 +522,9 @@ static void set_track(struct kmem_cache *s, void *object, trace.max_entries = TRACK_ADDRS_COUNT; trace.entries = p->addrs; trace.skip = 3; + metadata_access_enable(); save_stack_trace(&trace); + metadata_access_disable(); /* See rant in lockdep.c */ if (trace.nr_entries != 0 && @@ -677,7 +698,9 @@ static int check_bytes_and_report(struct kmem_cache *s, struct page *page, u8 *fault; u8 *end; + metadata_access_enable(); fault = memchr_inv(start, value, bytes); + metadata_access_disable(); if (!fault) return 1; @@ -770,7 +793,9 @@ static int slab_pad_check(struct kmem_cache *s, struct page *page) if (!remainder) return 1; + metadata_access_enable(); fault = memchr_inv(end - remainder, POISON_INUSE, remainder); + metadata_access_disable(); if (!fault) return 1; while (end > fault && end[-1] == POISON_INUSE) |