From f4957d5bd09165b165df851fbf8c658f7fcd9922 Mon Sep 17 00:00:00 2001 From: Alexey Dobriyan Date: Thu, 5 Apr 2018 16:20:37 -0700 Subject: [PATCH] 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@gmail.com Signed-off-by: Alexey Dobriyan Cc: Christoph Lameter Cc: Pekka Enberg Cc: David Rientjes Cc: Joonsoo Kim Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- 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 --git a/include/linux/slab.h b/include/linux/slab.h index ad157fbf3886..d36e8f03730e 100644 --- a/include/linux/slab.h +++ b/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 --git a/mm/slab.c b/mm/slab.c index 9095c3945425..ba25d8363eb2 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -1877,7 +1877,7 @@ slab_flags_t kmem_cache_flags(unsigned long object_size, } 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 --git a/mm/slab.h b/mm/slab.h index 2a6d88044a56..0809580428fe 100644 --- a/mm/slab.h +++ b/mm/slab.h @@ -101,11 +101,11 @@ extern void create_boot_cache(struct kmem_cache *, const char *name, 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 long object_size, 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 --git a/mm/slab_common.c b/mm/slab_common.c index 2a7f09ce7c84..a4545a61a7c8 100644 --- a/mm/slab_common.c +++ b/mm/slab_common.c @@ -82,7 +82,7 @@ unsigned int kmem_cache_size(struct kmem_cache *s) 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 char *name, size_t size) 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(struct kmem_cache *s) * 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(slab_flags_t flags, * 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 *s) 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 size, size_t align, } 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 --git a/mm/slub.c b/mm/slub.c index d92218ed7f1c..495c785c8d7e 100644 --- a/mm/slub.c +++ b/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; -- 2.30.2