[dpdk-dev] [PATCH v4 3/9] mem: fix potential double close

[Anatoly Burakov]

We were closing descriptor before checking if mapping has
failed, but if it did, we did a second close afterwards. Fix
it by moving closing descriptor to after we've done all error
checks.

Coverity issue: 272560

Fixes: 2a04139f66b4 ("eal: add single file segments option")
Cc: anatoly.burakov at intel.com

Signed-off-by: Anatoly Burakov <anatoly.burakov at intel.com>
---

Notes:
    v4:
    - Moved fd close to until after all error checks are done

 lib/librte_eal/linuxapp/eal/eal_memalloc.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/lib/librte_eal/linuxapp/eal/eal_memalloc.c b/lib/librte_eal/linuxapp/eal/eal_memalloc.c
index 1f553dd..3391ed1 100644
--- a/lib/librte_eal/linuxapp/eal/eal_memalloc.c
+++ b/lib/librte_eal/linuxapp/eal/eal_memalloc.c
@@ -458,9 +458,6 @@ alloc_seg(struct rte_memseg *ms, void *addr, int socket_id,
 	 */
 	void *va = mmap(addr, alloc_sz, PROT_READ | PROT_WRITE,
 			MAP_SHARED | MAP_POPULATE | MAP_FIXED, fd, map_offset);
-	/* for non-single file segments, we can close fd here */
-	if (!internal_config.single_file_segments)
-		close(fd);
 
 	if (va == MAP_FAILED) {
 		RTE_LOG(DEBUG, EAL, "%s(): mmap() failed: %s\n", __func__,
@@ -502,6 +499,10 @@ alloc_seg(struct rte_memseg *ms, void *addr, int socket_id,
 			(unsigned int)(alloc_sz >> 20));
 		goto mapped;
 	}
+	/* for non-single file segments, we can close fd here */
+	if (!internal_config.single_file_segments)
+		close(fd);
+
 	*(int *)addr = *(int *)addr;
 
 	ms->addr = addr;
-- 
2.7.4