From: Alexey Dobriyan <adobriyan@xxxxxxxxx> Subject: slab: make kmem_cache_create() work with 32-bit sizes struct kmem_cache::size and ::align were always 32-bit. Out of curiosity I created 4GB kmem_cache, it oopsed with division by 0. kmem_cache_create(1UL<<32+1) created 1-byte cache as expected. size_t doesn't work and never did. Link: http://lkml.kernel.org/r/20180305200730.15812-6-adobriyan@xxxxxxxxx Signed-off-by: Alexey Dobriyan <adobriyan@xxxxxxxxx> Cc: Christoph Lameter <cl@xxxxxxxxx> Cc: Pekka Enberg <penberg@xxxxxxxxxx> Cc: David Rientjes <rientjes@xxxxxxxxxx> Cc: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/linux/slab.h | 7 ++++--- mm/slab.c | 2 +- mm/slab.h | 6 +++--- mm/slab_common.c | 19 ++++++++++--------- mm/slub.c | 2 +- 5 files changed, 19 insertions(+), 17 deletions(-) diff -puN include/linux/slab.h~slab-make-kmem_cache_create-work-with-32-bit-sizes include/linux/slab.h --- a/include/linux/slab.h~slab-make-kmem_cache_create-work-with-32-bit-sizes +++ a/include/linux/slab.h @@ -137,11 +137,12 @@ bool slab_is_available(void); extern bool usercopy_fallback; -struct kmem_cache *kmem_cache_create(const char *name, size_t size, - size_t align, slab_flags_t flags, +struct kmem_cache *kmem_cache_create(const char *name, unsigned int size, + unsigned int align, slab_flags_t flags, void (*ctor)(void *)); struct kmem_cache *kmem_cache_create_usercopy(const char *name, - size_t size, size_t align, slab_flags_t flags, + unsigned int size, unsigned int align, + slab_flags_t flags, size_t useroffset, size_t usersize, void (*ctor)(void *)); void kmem_cache_destroy(struct kmem_cache *); diff -puN mm/slab.c~slab-make-kmem_cache_create-work-with-32-bit-sizes mm/slab.c --- a/mm/slab.c~slab-make-kmem_cache_create-work-with-32-bit-sizes +++ a/mm/slab.c @@ -1877,7 +1877,7 @@ slab_flags_t kmem_cache_flags(unsigned l } struct kmem_cache * -__kmem_cache_alias(const char *name, size_t size, size_t align, +__kmem_cache_alias(const char *name, unsigned int size, unsigned int align, slab_flags_t flags, void (*ctor)(void *)) { struct kmem_cache *cachep; diff -puN mm/slab_common.c~slab-make-kmem_cache_create-work-with-32-bit-sizes mm/slab_common.c --- a/mm/slab_common.c~slab-make-kmem_cache_create-work-with-32-bit-sizes +++ a/mm/slab_common.c @@ -82,7 +82,7 @@ unsigned int kmem_cache_size(struct kmem EXPORT_SYMBOL(kmem_cache_size); #ifdef CONFIG_DEBUG_VM -static int kmem_cache_sanity_check(const char *name, size_t size) +static int kmem_cache_sanity_check(const char *name, unsigned int size) { struct kmem_cache *s = NULL; @@ -113,7 +113,7 @@ static int kmem_cache_sanity_check(const return 0; } #else -static inline int kmem_cache_sanity_check(const char *name, size_t size) +static inline int kmem_cache_sanity_check(const char *name, unsigned int size) { return 0; } @@ -280,8 +280,8 @@ static inline void memcg_unlink_cache(st * Figure out what the alignment of the objects will be given a set of * flags, a user specified alignment and the size of the objects. */ -static unsigned long calculate_alignment(slab_flags_t flags, - unsigned long align, unsigned long size) +static unsigned int calculate_alignment(slab_flags_t flags, + unsigned int align, unsigned int size) { /* * If the user wants hardware cache aligned objects then follow that @@ -291,7 +291,7 @@ static unsigned long calculate_alignment * alignment though. If that is greater then use it. */ if (flags & SLAB_HWCACHE_ALIGN) { - unsigned long ralign; + unsigned int ralign; ralign = cache_line_size(); while (size <= ralign / 2) @@ -331,7 +331,7 @@ int slab_unmergeable(struct kmem_cache * return 0; } -struct kmem_cache *find_mergeable(size_t size, size_t align, +struct kmem_cache *find_mergeable(unsigned int size, unsigned int align, slab_flags_t flags, const char *name, void (*ctor)(void *)) { struct kmem_cache *s; @@ -379,7 +379,7 @@ struct kmem_cache *find_mergeable(size_t } static struct kmem_cache *create_cache(const char *name, - size_t object_size, size_t size, size_t align, + unsigned int object_size, unsigned int size, unsigned int align, slab_flags_t flags, size_t useroffset, size_t usersize, void (*ctor)(void *), struct mem_cgroup *memcg, struct kmem_cache *root_cache) @@ -452,7 +452,8 @@ out_free_cache: * as davem. */ struct kmem_cache * -kmem_cache_create_usercopy(const char *name, size_t size, size_t align, +kmem_cache_create_usercopy(const char *name, + unsigned int size, unsigned int align, slab_flags_t flags, size_t useroffset, size_t usersize, void (*ctor)(void *)) { @@ -532,7 +533,7 @@ out_unlock: EXPORT_SYMBOL(kmem_cache_create_usercopy); struct kmem_cache * -kmem_cache_create(const char *name, size_t size, size_t align, +kmem_cache_create(const char *name, unsigned int size, unsigned int align, slab_flags_t flags, void (*ctor)(void *)) { return kmem_cache_create_usercopy(name, size, align, flags, 0, 0, diff -puN mm/slab.h~slab-make-kmem_cache_create-work-with-32-bit-sizes mm/slab.h --- a/mm/slab.h~slab-make-kmem_cache_create-work-with-32-bit-sizes +++ a/mm/slab.h @@ -101,11 +101,11 @@ extern void create_boot_cache(struct kme unsigned int useroffset, unsigned int usersize); int slab_unmergeable(struct kmem_cache *s); -struct kmem_cache *find_mergeable(size_t size, size_t align, +struct kmem_cache *find_mergeable(unsigned size, unsigned align, slab_flags_t flags, const char *name, void (*ctor)(void *)); #ifndef CONFIG_SLOB struct kmem_cache * -__kmem_cache_alias(const char *name, size_t size, size_t align, +__kmem_cache_alias(const char *name, unsigned int size, unsigned int align, slab_flags_t flags, void (*ctor)(void *)); slab_flags_t kmem_cache_flags(unsigned long object_size, @@ -113,7 +113,7 @@ slab_flags_t kmem_cache_flags(unsigned l void (*ctor)(void *)); #else static inline struct kmem_cache * -__kmem_cache_alias(const char *name, size_t size, size_t align, +__kmem_cache_alias(const char *name, unsigned int size, unsigned int align, slab_flags_t flags, void (*ctor)(void *)) { return NULL; } diff -puN mm/slub.c~slab-make-kmem_cache_create-work-with-32-bit-sizes mm/slub.c --- a/mm/slub.c~slab-make-kmem_cache_create-work-with-32-bit-sizes +++ a/mm/slub.c @@ -4242,7 +4242,7 @@ void __init kmem_cache_init_late(void) } struct kmem_cache * -__kmem_cache_alias(const char *name, size_t size, size_t align, +__kmem_cache_alias(const char *name, unsigned int size, unsigned int align, slab_flags_t flags, void (*ctor)(void *)) { struct kmem_cache *s, *c; _ -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
