From 4e3ca3e033d1eea62fa16c3fdbef4f20427bd0de Mon Sep 17 00:00:00 2001 From: Sergey Senozhatsky Date: Tue, 8 Sep 2015 15:00:53 -0700 Subject: [PATCH] mm/mempool: allow NULL `pool' pointer in mempool_destroy() mempool_destroy() does not tolerate a NULL mempool_t pointer argument and performs a NULL-pointer dereference. This requires additional attention and effort from developers/reviewers and forces all mempool_destroy() callers to do a NULL check if (pool) mempool_destroy(pool); Or, otherwise, be invalid mempool_destroy() users. Tweak mempool_destroy() and NULL-check the pointer there. Proposed by Andrew Morton. Link: https://lkml.org/lkml/2015/6/8/583 Signed-off-by: Sergey Senozhatsky Acked-by: David Rientjes Cc: Julia Lawall Cc: Joe Perches Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/mempool.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/mm/mempool.c b/mm/mempool.c index 2cc08de8b1db..4c533bc51d73 100644 --- a/mm/mempool.c +++ b/mm/mempool.c @@ -150,6 +150,9 @@ static void *remove_element(mempool_t *pool) */ void mempool_destroy(mempool_t *pool) { + if (unlikely(!pool)) + return; + while (pool->curr_nr) { void *element = remove_element(pool); pool->free(element, pool->pool_data); -- 2.39.5