diff mbox

[dpdk-dev] malloc: fix pad erasing

Message ID 9342b8f957343940a9a957a64853bd185db5b3c8.1527784022.git.anatoly.burakov@intel.com (mailing list archive)
State Accepted, archived
Delegated to: Thomas Monjalon
Headers

Checks

Context Check Description
ci/checkpatch success coding style OK
ci/Intel-compilation success Compilation OK

Commit Message

Anatoly Burakov May 31, 2018, 5:05 p.m. UTC 
  Previously, when joining adjacent free elements, we were erasing
trailer and header, but did not erase the padding. Fix this by
accounting for padding on erase, and do not erase padding twice
by adjusting data pointer and data len to not include padding.

Fixes: bb372060dad4 ("malloc: make heap a doubly-linked list")
Cc: stable@dpdk.org

Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>
---
 lib/librte_eal/common/malloc_elem.c | 16 ++++++++++------
 1 file changed, 10 insertions(+), 6 deletions(-)

Comments

Thomas Monjalon July 13, 2018, 9:22 a.m. UTC | #1 
31/05/2018 19:05, Anatoly Burakov:
> Previously, when joining adjacent free elements, we were erasing
> trailer and header, but did not erase the padding. Fix this by
> accounting for padding on erase, and do not erase padding twice
> by adjusting data pointer and data len to not include padding.
> 
> Fixes: bb372060dad4 ("malloc: make heap a doubly-linked list")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>

Applied, thanks
diff mbox

Patch

diff --git a/lib/librte_eal/common/malloc_elem.c b/lib/librte_eal/common/malloc_elem.c
index 9bfe9b9b4..944587bc5 100644
--- a/lib/librte_eal/common/malloc_elem.c
+++ b/lib/librte_eal/common/malloc_elem.c
@@ -386,16 +386,18 @@  malloc_elem_join_adjacent_free(struct malloc_elem *elem)
 	if (elem->next != NULL && elem->next->state == ELEM_FREE &&
 			next_elem_is_adjacent(elem)) {
 		void *erase;
+		size_t erase_len;
 
 		/* we will want to erase the trailer and header */
 		erase = RTE_PTR_SUB(elem->next, MALLOC_ELEM_TRAILER_LEN);
+		erase_len = MALLOC_ELEM_OVERHEAD + elem->next->pad;
 
 		/* remove from free list, join to this one */
 		malloc_elem_free_list_remove(elem->next);
 		join_elem(elem, elem->next);
 
-		/* erase header and trailer */
-		memset(erase, 0, MALLOC_ELEM_OVERHEAD);
+		/* erase header, trailer and pad */
+		memset(erase, 0, erase_len);
 	}
 
 	/*
@@ -406,9 +408,11 @@  malloc_elem_join_adjacent_free(struct malloc_elem *elem)
 			prev_elem_is_adjacent(elem)) {
 		struct malloc_elem *new_elem;
 		void *erase;
+		size_t erase_len;
 
 		/* we will want to erase trailer and header */
 		erase = RTE_PTR_SUB(elem, MALLOC_ELEM_TRAILER_LEN);
+		erase_len = MALLOC_ELEM_OVERHEAD + elem->pad;
 
 		/* remove from free list, join to this one */
 		malloc_elem_free_list_remove(elem->prev);
@@ -416,8 +420,8 @@  malloc_elem_join_adjacent_free(struct malloc_elem *elem)
 		new_elem = elem->prev;
 		join_elem(new_elem, elem);
 
-		/* erase header and trailer */
-		memset(erase, 0, MALLOC_ELEM_OVERHEAD);
+		/* erase header, trailer and pad */
+		memset(erase, 0, erase_len);
 
 		elem = new_elem;
 	}
@@ -436,8 +440,8 @@  malloc_elem_free(struct malloc_elem *elem)
 	void *ptr;
 	size_t data_len;
 
-	ptr = RTE_PTR_ADD(elem, sizeof(*elem));
-	data_len = elem->size - MALLOC_ELEM_OVERHEAD;
+	ptr = RTE_PTR_ADD(elem, MALLOC_ELEM_HEADER_LEN + elem->pad);
+	data_len = elem->size - elem->pad - MALLOC_ELEM_OVERHEAD;
 
 	elem = malloc_elem_join_adjacent_free(elem);