summaryrefslogtreecommitdiff
path: root/mm/kasan
diff options
context:
space:
mode:
authorAndrey Konovalov <andreyknvl@google.com>2023-12-20 01:28:55 +0300
committerAndrew Morton <akpm@linux-foundation.org>2023-12-29 22:58:38 +0300
commit0cc9fdbf4a5273310779bd4779fcdfb4705438a6 (patch)
tree92ac5667636858860244ea072c6d63b367ebd852 /mm/kasan
parentce37eec0ab62fb1f04509b83161845859815ee13 (diff)
downloadlinux-0cc9fdbf4a5273310779bd4779fcdfb4705438a6.tar.xz
kasan: introduce poison_kmalloc_large_redzone
Split out a poison_kmalloc_large_redzone helper from __kasan_kmalloc_large and use it in the caller's code. This is a preparatory change for the following patches in this series. Link: https://lkml.kernel.org/r/93317097b668519d76097fb065201b2027436e22.1703024586.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Cc: Alexander Lobakin <alobakin@pm.me> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Breno Leitao <leitao@debian.org> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Evgenii Stepanov <eugenis@google.com> Cc: Marco Elver <elver@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'mm/kasan')
-rw-r--r--mm/kasan/common.c41
1 files changed, 23 insertions, 18 deletions
diff --git a/mm/kasan/common.c b/mm/kasan/common.c
index 1217b260abc3..962805bf5f62 100644
--- a/mm/kasan/common.c
+++ b/mm/kasan/common.c
@@ -363,23 +363,12 @@ void * __must_check __kasan_kmalloc(struct kmem_cache *cache, const void *object
}
EXPORT_SYMBOL(__kasan_kmalloc);
-void * __must_check __kasan_kmalloc_large(const void *ptr, size_t size,
+static inline void poison_kmalloc_large_redzone(const void *ptr, size_t size,
gfp_t flags)
{
unsigned long redzone_start;
unsigned long redzone_end;
- if (gfpflags_allow_blocking(flags))
- kasan_quarantine_reduce();
-
- if (unlikely(ptr == NULL))
- return NULL;
-
- /*
- * The object has already been unpoisoned by kasan_unpoison_pages() for
- * alloc_pages() or by kasan_krealloc() for krealloc().
- */
-
/*
* The redzone has byte-level precision for the generic mode.
* Partially poison the last object granule to cover the unaligned
@@ -389,12 +378,25 @@ void * __must_check __kasan_kmalloc_large(const void *ptr, size_t size,
kasan_poison_last_granule(ptr, size);
/* Poison the aligned part of the redzone. */
- redzone_start = round_up((unsigned long)(ptr + size),
- KASAN_GRANULE_SIZE);
+ redzone_start = round_up((unsigned long)(ptr + size), KASAN_GRANULE_SIZE);
redzone_end = (unsigned long)ptr + page_size(virt_to_page(ptr));
kasan_poison((void *)redzone_start, redzone_end - redzone_start,
KASAN_PAGE_REDZONE, false);
+}
+void * __must_check __kasan_kmalloc_large(const void *ptr, size_t size,
+ gfp_t flags)
+{
+ if (gfpflags_allow_blocking(flags))
+ kasan_quarantine_reduce();
+
+ if (unlikely(ptr == NULL))
+ return NULL;
+
+ /* The object has already been unpoisoned by kasan_unpoison_pages(). */
+ poison_kmalloc_large_redzone(ptr, size, flags);
+
+ /* Keep the tag that was set by alloc_pages(). */
return (void *)ptr;
}
@@ -402,6 +404,9 @@ void * __must_check __kasan_krealloc(const void *object, size_t size, gfp_t flag
{
struct slab *slab;
+ if (gfpflags_allow_blocking(flags))
+ kasan_quarantine_reduce();
+
if (unlikely(object == ZERO_SIZE_PTR))
return (void *)object;
@@ -419,11 +424,11 @@ void * __must_check __kasan_krealloc(const void *object, size_t size, gfp_t flag
/* Piggy-back on kmalloc() instrumentation to poison the redzone. */
if (unlikely(!slab))
- return __kasan_kmalloc_large(object, size, flags);
- else {
+ poison_kmalloc_large_redzone(object, size, flags);
+ else
poison_kmalloc_redzone(slab->slab_cache, object, size, flags);
- return (void *)object;
- }
+
+ return (void *)object;
}
bool __kasan_mempool_poison_pages(struct page *page, unsigned int order,