| Message ID | 91406e5f2a1c0a1fddfc4e7f17df22fda852591c.1655150842.git.andreyknvl@google.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | kasan: switch tag-based modes to stack ring from per-object metadata | expand |
On Mon, 13 Jun 2022 at 22:15, <andrey.konovalov@linux.dev> wrote: > > From: Andrey Konovalov <andreyknvl@google.com> > > __kasan_metadata_size() calculates the size of the redzone for objects > in a slab cache. > > When accounting for presence of kasan_free_meta in the redzone, this > function only compares free_meta_offset with 0. But free_meta_offset could > also be equal to KASAN_NO_FREE_META, which indicates that kasan_free_meta > is not present at all. > > Add a comparison with KASAN_NO_FREE_META into __kasan_metadata_size(). > > Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Reviewed-by: Marco Elver <elver@google.com> > --- > > This is a minor fix that only affects slub_debug runs, so it is probably > not worth backporting. > --- > mm/kasan/common.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/mm/kasan/common.c b/mm/kasan/common.c > index c40c0e7b3b5f..968d2365d8c1 100644 > --- a/mm/kasan/common.c > +++ b/mm/kasan/common.c > @@ -223,8 +223,9 @@ size_t __kasan_metadata_size(struct kmem_cache *cache) > return 0; > return (cache->kasan_info.alloc_meta_offset ? > sizeof(struct kasan_alloc_meta) : 0) + > - (cache->kasan_info.free_meta_offset ? > - sizeof(struct kasan_free_meta) : 0); > + ((cache->kasan_info.free_meta_offset && > + cache->kasan_info.free_meta_offset != KASAN_NO_FREE_META) ? > + sizeof(struct kasan_free_meta) : 0); > } > > struct kasan_alloc_meta *kasan_get_alloc_meta(struct kmem_cache *cache, > -- > 2.25.1 > > -- > You received this message because you are subscribed to the Google Groups "kasan-dev" group. > To unsubscribe from this group and stop receiving emails from it, send an email to kasan-dev+unsubscribe@googlegroups.com. > To view this discussion on the web visit https://groups.google.com/d/msgid/kasan-dev/91406e5f2a1c0a1fddfc4e7f17df22fda852591c.1655150842.git.andreyknvl%40google.com.
diff --git a/mm/kasan/common.c b/mm/kasan/common.c index c40c0e7b3b5f..968d2365d8c1 100644 --- a/mm/kasan/common.c +++ b/mm/kasan/common.c @@ -223,8 +223,9 @@ size_t __kasan_metadata_size(struct kmem_cache *cache) return 0; return (cache->kasan_info.alloc_meta_offset ? sizeof(struct kasan_alloc_meta) : 0) + - (cache->kasan_info.free_meta_offset ? - sizeof(struct kasan_free_meta) : 0); + ((cache->kasan_info.free_meta_offset && + cache->kasan_info.free_meta_offset != KASAN_NO_FREE_META) ? + sizeof(struct kasan_free_meta) : 0); } struct kasan_alloc_meta *kasan_get_alloc_meta(struct kmem_cache *cache,