[PATCH RFC 03/20] kasan: document kasan_mempool_poison_object

From: andrey . konovalov
Date: Mon Nov 06 2023 - 15:10:48 EST


From: Andrey Konovalov <andreyknvl@xxxxxxxxxx>

Add documentation comment for kasan_mempool_poison_object.

Signed-off-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx>
---
include/linux/kasan.h | 18 ++++++++++++++++++
1 file changed, 18 insertions(+)

diff --git a/include/linux/kasan.h b/include/linux/kasan.h
index 0d1f925c136d..bbf6e2fa4ffd 100644
--- a/include/linux/kasan.h
+++ b/include/linux/kasan.h
@@ -213,6 +213,24 @@ static __always_inline void * __must_check kasan_krealloc(const void *object,
}

void __kasan_mempool_poison_object(void *ptr, unsigned long ip);
+/**
+ * kasan_mempool_poison_object - Check and poison a mempool slab allocation.
+ * @ptr: Pointer to the slab allocation.
+ *
+ * This function is intended for kernel subsystems that cache slab allocations
+ * to reuse them instead of freeing them back to the slab allocator (e.g.
+ * mempool).
+ *
+ * This function poisons a slab allocation without initializing its memory and
+ * without putting it into the quarantine (for the Generic mode).
+ *
+ * This function also performs checks to detect double-free and invalid-free
+ * bugs and reports them.
+ *
+ * This function operates on all slab allocations including large kmalloc
+ * allocations (the ones returned by kmalloc_large() or by kmalloc() with the
+ * size > KMALLOC_MAX_SIZE).
+ */
static __always_inline void kasan_mempool_poison_object(void *ptr)
{
if (kasan_enabled())
--
2.25.1