From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jamie Lavigne Subject: [PATCH v3] mem: fix malloc_elem resize with padding Date: Thu, 8 Jun 2017 19:12:17 +0000 Message-ID: <1496949137-8106-1-git-send-email-lavignen@amazon.com> References: <1496189818-2307-1-git-send-email-lavignen@amazon.com> Mime-Version: 1.0 Content-Type: text/plain Cc: , Jamie Lavigne To: Return-path: Received: from smtp-fw-33001.amazon.com (smtp-fw-33001.amazon.com [207.171.190.10]) by dpdk.org (Postfix) with ESMTP id 60DF0271 for ; Thu, 8 Jun 2017 21:13:10 +0200 (CEST) In-Reply-To: <1496189818-2307-1-git-send-email-lavignen@amazon.com> List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" Currently when a malloc_elem is split after resizing, any padding present in the elem is ignored. This causes the resized elem to be too small when padding is present, and user data can overwrite the beginning of the following malloc_elem. Solve this by including the size of the padding when computing where to split the malloc_elem. Fixes: af75078fece3 ("first public release") Signed-off-by: Jamie Lavigne --- lib/librte_eal/common/malloc_elem.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/lib/librte_eal/common/malloc_elem.c b/lib/librte_eal/common/malloc_elem.c index 42568e1..08516af 100644 --- a/lib/librte_eal/common/malloc_elem.c +++ b/lib/librte_eal/common/malloc_elem.c @@ -314,17 +314,16 @@ malloc_elem_free(struct malloc_elem *elem) int malloc_elem_resize(struct malloc_elem *elem, size_t size) { - const size_t new_size = size + MALLOC_ELEM_OVERHEAD; + const size_t new_size = size + elem->pad + MALLOC_ELEM_OVERHEAD; /* if we request a smaller size, then always return ok */ - const size_t current_size = elem->size - elem->pad; - if (current_size >= new_size) + if (elem->size >= new_size) return 0; struct malloc_elem *next = RTE_PTR_ADD(elem, elem->size); rte_spinlock_lock(&elem->heap->lock); if (next ->state != ELEM_FREE) goto err_return; - if (current_size + next->size < new_size) + if (elem->size + next->size < new_size) goto err_return; /* we now know the element fits, so remove from free list, @@ -333,7 +332,7 @@ malloc_elem_resize(struct malloc_elem *elem, size_t size) elem_free_list_remove(next); join_elem(elem, next); - if (elem->size - new_size >= MIN_DATA_SIZE + MALLOC_ELEM_OVERHEAD){ + if (elem->size - new_size >= MIN_DATA_SIZE + MALLOC_ELEM_OVERHEAD) { /* now we have a big block together. Lets cut it down a bit, by splitting */ struct malloc_elem *split_pt = RTE_PTR_ADD(elem, new_size); split_pt = RTE_PTR_ALIGN_CEIL(split_pt, RTE_CACHE_LINE_SIZE); -- 2.7.3.AMZN