The patch titled
Subject: kasan: clean up and rename ____kasan_kmalloc
has been added to the -mm mm-unstable branch. Its filename is
kasan-clean-up-and-rename-____kasan_kmalloc.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/kasan-clean-up-and-rename-____kasan_kmalloc.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Andrey Konovalov <andreyknvl@xxxxxxxxxx>
Subject: kasan: clean up and rename ____kasan_kmalloc
Date: Tue, 19 Dec 2023 23:28:54 +0100
Introduce a new poison_kmalloc_redzone helper function that poisons the
redzone for kmalloc object.
Drop the confusingly named ____kasan_kmalloc function and instead use
poison_kmalloc_redzone along with the other required parts of
____kasan_kmalloc in the callers' code.
This is a preparatory change for the following patches in this series.
Link: https://lkml.kernel.org/r/5881232ad357ec0d59a5b1aefd9e0673a386399a.1703024586.git.andreyknvl@xxxxxxxxxx
Signed-off-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx>
Cc: Alexander Lobakin <alobakin@xxxxx>
Cc: Alexander Potapenko <glider@xxxxxxxxxx>
Cc: Andrey Ryabinin <ryabinin.a.a@xxxxxxxxx>
Cc: Breno Leitao <leitao@xxxxxxxxxx>
Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx>
Cc: Evgenii Stepanov <eugenis@xxxxxxxxxx>
Cc: Marco Elver <elver@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/kasan/common.c | 42 ++++++++++++++++++++++--------------------
1 file changed, 22 insertions(+), 20 deletions(-)
--- a/mm/kasan/common.c~kasan-clean-up-and-rename-____kasan_kmalloc
+++ a/mm/kasan/common.c
@@ -312,26 +312,12 @@ void * __must_check __kasan_slab_alloc(s
return tagged_object;
}
-static inline void *____kasan_kmalloc(struct kmem_cache *cache,
+static inline void poison_kmalloc_redzone(struct kmem_cache *cache,
const void *object, size_t size, gfp_t flags)
{
unsigned long redzone_start;
unsigned long redzone_end;
- if (gfpflags_allow_blocking(flags))
- kasan_quarantine_reduce();
-
- if (unlikely(object == NULL))
- return NULL;
-
- if (is_kfence_address(kasan_reset_tag(object)))
- return (void *)object;
-
- /*
- * The object has already been unpoisoned by kasan_slab_alloc() for
- * kmalloc() 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
@@ -355,14 +341,25 @@ static inline void *____kasan_kmalloc(st
if (kasan_stack_collection_enabled() && is_kmalloc_cache(cache))
kasan_save_alloc_info(cache, (void *)object, flags);
- /* Keep the tag that was set by kasan_slab_alloc(). */
- return (void *)object;
}
void * __must_check __kasan_kmalloc(struct kmem_cache *cache, const void *object,
size_t size, gfp_t flags)
{
- return ____kasan_kmalloc(cache, object, size, flags);
+ if (gfpflags_allow_blocking(flags))
+ kasan_quarantine_reduce();
+
+ if (unlikely(object == NULL))
+ return NULL;
+
+ if (is_kfence_address(kasan_reset_tag(object)))
+ return (void *)object;
+
+ /* The object has already been unpoisoned by kasan_slab_alloc(). */
+ poison_kmalloc_redzone(cache, object, size, flags);
+
+ /* Keep the tag that was set by kasan_slab_alloc(). */
+ return (void *)object;
}
EXPORT_SYMBOL(__kasan_kmalloc);
@@ -408,6 +405,9 @@ void * __must_check __kasan_krealloc(con
if (unlikely(object == ZERO_SIZE_PTR))
return (void *)object;
+ if (is_kfence_address(kasan_reset_tag(object)))
+ return (void *)object;
+
/*
* Unpoison the object's data.
* Part of it might already have been unpoisoned, but it's unknown
@@ -420,8 +420,10 @@ void * __must_check __kasan_krealloc(con
/* Piggy-back on kmalloc() instrumentation to poison the redzone. */
if (unlikely(!slab))
return __kasan_kmalloc_large(object, size, flags);
- else
- return ____kasan_kmalloc(slab->slab_cache, object, size, flags);
+ else {
+ poison_kmalloc_redzone(slab->slab_cache, object, size, flags);
+ return (void *)object;
+ }
}
bool __kasan_mempool_poison_pages(struct page *page, unsigned int order,
_
Patches currently in -mm which might be from andreyknvl@xxxxxxxxxx are
kasan-rename-kasan_slab_free_mempool-to-kasan_mempool_poison_object.patch
kasan-move-kasan_mempool_poison_object.patch
kasan-document-kasan_mempool_poison_object.patch
kasan-add-return-value-for-kasan_mempool_poison_object.patch
kasan-introduce-kasan_mempool_unpoison_object.patch
kasan-introduce-kasan_mempool_poison_pages.patch
kasan-introduce-kasan_mempool_unpoison_pages.patch
kasan-clean-up-__kasan_mempool_poison_object.patch
kasan-save-free-stack-traces-for-slab-mempools.patch
kasan-clean-up-and-rename-____kasan_kmalloc.patch
kasan-introduce-poison_kmalloc_large_redzone.patch
kasan-save-alloc-stack-traces-for-mempool.patch
mempool-skip-slub_debug-poisoning-when-kasan-is-enabled.patch
mempool-use-new-mempool-kasan-hooks.patch
mempool-introduce-mempool_use_prealloc_only.patch
kasan-add-mempool-tests.patch
kasan-rename-pagealloc-tests.patch
kasan-reorder-tests.patch
kasan-rename-and-document-kasan_unpoison_object_data.patch
skbuff-use-mempool-kasan-hooks.patch
io_uring-use-mempool-kasan-hook.patch
