slab: Return NULL for oversized allocations
The inline path seems to have changed the SLAB behavior for very large
kmalloc allocations with commit e3366016 ("slab: Use common
kmalloc_index/kmalloc_size functions"). This patch restores the old
behavior but also adds diagnostics so that we can figure where in the
code these large allocations occur.
Reported-and-tested-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Christoph Lameter <cl@linux.com>
Link: http://lkml.kernel.org/r/201305040348.CIF81716.OStQOHFJMFLOVF@I-love.SAKURA.ne.jp
[ penberg@kernel.org: use WARN_ON_ONCE ]
Signed-off-by: Pekka Enberg <penberg@kernel.org>
diff --git a/mm/slab_common.c b/mm/slab_common.c
index 2f0e7d5..c5d352e 100644
--- a/mm/slab_common.c
+++ b/mm/slab_common.c
@@ -373,6 +373,9 @@
{
int index;
+ if (WARN_ON_ONCE(size > KMALLOC_MAX_SIZE))
+ return NULL;
+
if (size <= 192) {
if (!size)
return ZERO_SIZE_PTR;