[dpdk-dev] [PATCH] eal/malloc: fix malloc cookie check

Xueming Li xuemingl at mellanox.com
Wed Aug 23 04:29:26 CEST 2017


From: xuemingl <xuemingl at mellanox.com>

DPDK uses it's own memory management, few regular memory profiler tool
support DPDK now. Malloc cookie check provides limited memory corruption
check, better than nothing. This patch fixes the following:
1. Replace broken generated configuration macro RTE_LIBRTE_MALLOC_DEBUG
with RTE_MALLOC_DEBUG
2. Fix malloc size calculation when RTE_MALLOC_DEBUG cookie check
enabled.

>From real test, it IS very helpful to detect memory corruption.

A better designed DPDK application should quit nicely with resoure
releasing so that all allocated memory could be checked against cookie.

Fixes: af75078 ("first public release")
Cc: Sergio Gonzalez Monroy <sergio.gonzalez.monroy at intel.com>

Signed-off-by: Xueming Li <xuemingl at mellanox.com>
---
 lib/librte_eal/common/malloc_elem.c |  8 ++++----
 lib/librte_eal/common/malloc_elem.h |  4 ++--
 test/test/test_malloc.c             | 10 +++++-----
 3 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/lib/librte_eal/common/malloc_elem.c b/lib/librte_eal/common/malloc_elem.c
index 150769057..889dffd21 100644
--- a/lib/librte_eal/common/malloc_elem.c
+++ b/lib/librte_eal/common/malloc_elem.c
@@ -275,14 +275,14 @@ malloc_elem_free(struct malloc_elem *elem)
 		return -1;
 
 	rte_spinlock_lock(&(elem->heap->lock));
-	size_t sz = elem->size - sizeof(*elem);
+	size_t sz = elem->size - sizeof(*elem) - MALLOC_ELEM_TRAILER_LEN;
 	uint8_t *ptr = (uint8_t *)&elem[1];
 	struct malloc_elem *next = RTE_PTR_ADD(elem, elem->size);
 	if (next->state == ELEM_FREE){
 		/* remove from free list, join to this one */
 		elem_free_list_remove(next);
 		join_elem(elem, next);
-		sz += sizeof(*elem);
+		sz += (sizeof(*elem) + MALLOC_ELEM_TRAILER_LEN);
 	}
 
 	/* check if previous element is free, if so join with it and return,
@@ -291,8 +291,8 @@ malloc_elem_free(struct malloc_elem *elem)
 	if (elem->prev != NULL && elem->prev->state == ELEM_FREE) {
 		elem_free_list_remove(elem->prev);
 		join_elem(elem->prev, elem);
-		sz += sizeof(*elem);
-		ptr -= sizeof(*elem);
+		sz += (sizeof(*elem) + MALLOC_ELEM_TRAILER_LEN);
+		ptr -= (sizeof(*elem) + MALLOC_ELEM_TRAILER_LEN);
 		elem = elem->prev;
 	}
 	malloc_elem_free_list_insert(elem);
diff --git a/lib/librte_eal/common/malloc_elem.h b/lib/librte_eal/common/malloc_elem.h
index f04b2d1e4..ce39129d9 100644
--- a/lib/librte_eal/common/malloc_elem.h
+++ b/lib/librte_eal/common/malloc_elem.h
@@ -53,13 +53,13 @@ struct malloc_elem {
 	volatile enum elem_state state;
 	uint32_t pad;
 	size_t size;
-#ifdef RTE_LIBRTE_MALLOC_DEBUG
+#ifdef RTE_MALLOC_DEBUG
 	uint64_t header_cookie;         /* Cookie marking start of data */
 	                                /* trailer cookie at start + size */
 #endif
 } __rte_cache_aligned;
 
-#ifndef RTE_LIBRTE_MALLOC_DEBUG
+#ifndef RTE_MALLOC_DEBUG
 static const unsigned MALLOC_ELEM_TRAILER_LEN = 0;
 
 /* dummy function - just check if pointer is non-null */
diff --git a/test/test/test_malloc.c b/test/test/test_malloc.c
index 013fd4407..5558acda4 100644
--- a/test/test/test_malloc.c
+++ b/test/test/test_malloc.c
@@ -108,7 +108,7 @@ test_align_overlap_per_lcore(__attribute__((unused)) void *arg)
 		}
 		for(j = 0; j < 1000 ; j++) {
 			if( *(char *)p1 != 0) {
-				printf("rte_zmalloc didn't zero"
+				printf("rte_zmalloc didn't zero "
 				       "the allocated memory\n");
 				ret = -1;
 			}
@@ -180,7 +180,7 @@ test_reordered_free_per_lcore(__attribute__((unused)) void *arg)
 		}
 		for(j = 0; j < 1000 ; j++) {
 			if( *(char *)p1 != 0) {
-				printf("rte_zmalloc didn't zero"
+				printf("rte_zmalloc didn't zero "
 				       "the allocated memory\n");
 				ret = -1;
 			}
@@ -293,7 +293,7 @@ test_multi_alloc_statistics(void)
 	struct rte_malloc_socket_stats pre_stats, post_stats ,first_stats, second_stats;
 	size_t size = 2048;
 	int align = 1024;
-#ifndef RTE_LIBRTE_MALLOC_DEBUG
+#ifndef RTE_MALLOC_DEBUG
 	int trailer_size = 0;
 #else
 	int trailer_size = RTE_CACHE_LINE_SIZE;
@@ -623,7 +623,7 @@ test_rte_malloc_validate(void)
 	const size_t request_size = 1024;
 	size_t allocated_size;
 	char *data_ptr = rte_malloc(NULL, request_size, RTE_CACHE_LINE_SIZE);
-#ifdef RTE_LIBRTE_MALLOC_DEBUG
+#ifdef RTE_MALLOC_DEBUG
 	int retval;
 	char *over_write_vals = NULL;
 #endif
@@ -645,7 +645,7 @@ test_rte_malloc_validate(void)
 	if (allocated_size < request_size)
 		err_return();
 
-#ifdef RTE_LIBRTE_MALLOC_DEBUG
+#ifdef RTE_MALLOC_DEBUG
 
 	/****** change the header to be bad */
 	char save_buf[64];
-- 
2.13.3



More information about the dev mailing list