dma_pool_destroy() does not tolerate a NULL dma_pool pointer argument and performs a NULL-pointer dereference. This requires additional attention and effort from developers/reviewers and forces all dma_pool_destroy() callers to do a NULL check if (pool) dma_pool_destroy(pool); Or, otherwise, be invalid dma_pool_destroy() users. Tweak dma_pool_destroy() and NULL-check the pointer there. Proposed by Andrew Morton. Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@xxxxxxxxx> Reported-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> LKML-reference: https://lkml.org/lkml/2015/6/8/583 --- mm/dmapool.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/mm/dmapool.c b/mm/dmapool.c index fd5fe43..5f2cffc 100644 --- a/mm/dmapool.c +++ b/mm/dmapool.c @@ -271,6 +271,9 @@ void dma_pool_destroy(struct dma_pool *pool) { bool empty = false; + if (unlikely(!pool)) + return; + mutex_lock(&pools_reg_lock); mutex_lock(&pools_lock); list_del(&pool->pools); -- 2.4.3.368.g7974889 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>