[dpdk-dev] [PATCH v3] mem: fix memory leaks of hugedir and replace snprintf

[Yangchao Zhou]

The hugedir returned by get_hugepage_dir is allocated by strdup
 but not released. Replace snprintf with a more suitable strlcpy.

Coverity issue: 272585
Fixes: cb97d93e9d3b ("mem: share hugepage info primary and secondary")

Signed-off-by: Yangchao Zhou <zhouyates at gmail.com>
Acked-by: Anatoly Burakov <anatoly.burakov at intel.com>
---
 lib/librte_eal/bsdapp/eal/eal_hugepage_info.c   |    2 +-
 lib/librte_eal/linuxapp/eal/eal_hugepage_info.c |   18 +++++++++---------
 lib/librte_eal/linuxapp/eal/eal_memory.c        |    4 ++--
 3 files changed, 12 insertions(+), 12 deletions(-)

diff --git a/lib/librte_eal/bsdapp/eal/eal_hugepage_info.c b/lib/librte_eal/bsdapp/eal/eal_hugepage_info.c
index 38d143c..836feb6 100644
--- a/lib/librte_eal/bsdapp/eal/eal_hugepage_info.c
+++ b/lib/librte_eal/bsdapp/eal/eal_hugepage_info.c
@@ -96,7 +96,7 @@
 		RTE_LOG(INFO, EAL, "Contigmem driver has %d buffers, each of size %dKB\n",
 				num_buffers, (int)(buffer_size>>10));
 
-	snprintf(hpi->hugedir, sizeof(hpi->hugedir), "%s", CONTIGMEM_DEV);
+	strlcpy(hpi->hugedir, CONTIGMEM_DEV, sizeof(hpi->hugedir));
 	hpi->hugepage_sz = buffer_size;
 	hpi->num_pages[0] = num_buffers;
 	hpi->lock_descriptor = fd;
diff --git a/lib/librte_eal/linuxapp/eal/eal_hugepage_info.c b/lib/librte_eal/linuxapp/eal/eal_hugepage_info.c
index fb4b667..db5aabd 100644
--- a/lib/librte_eal/linuxapp/eal/eal_hugepage_info.c
+++ b/lib/librte_eal/linuxapp/eal/eal_hugepage_info.c
@@ -169,8 +169,8 @@
 	return size;
 }
 
-static const char *
-get_hugepage_dir(uint64_t hugepage_sz)
+static int
+get_hugepage_dir(uint64_t hugepage_sz, char *hugedir, int len)
 {
 	enum proc_mount_fieldnames {
 		DEVICE = 0,
@@ -188,7 +188,7 @@
 	const char split_tok = ' ';
 	char *splitstr[_FIELDNAME_MAX];
 	char buf[BUFSIZ];
-	char *retval = NULL;
+	int retval = -1;
 
 	FILE *fd = fopen(proc_mounts, "r");
 	if (fd == NULL)
@@ -215,7 +215,8 @@
 			/* if no explicit page size, the default page size is compared */
 			if (pagesz_str == NULL){
 				if (hugepage_sz == default_size){
-					retval = strdup(splitstr[MOUNTPT]);
+					strlcpy(hugedir, splitstr[MOUNTPT], len);
+					retval = 0;
 					break;
 				}
 			}
@@ -223,7 +224,8 @@
 			else {
 				uint64_t pagesz = rte_str_to_size(&pagesz_str[pagesize_opt_len]);
 				if (pagesz == hugepage_sz) {
-					retval = strdup(splitstr[MOUNTPT]);
+					strlcpy(hugedir, splitstr[MOUNTPT], len);
+					retval = 0;
 					break;
 				}
 			}
@@ -351,7 +353,6 @@
 
 	for (dirent = readdir(dir); dirent != NULL; dirent = readdir(dir)) {
 		struct hugepage_info *hpi;
-		const char *hugedir;
 
 		if (strncmp(dirent->d_name, dirent_start_text,
 			    dirent_start_len) != 0)
@@ -363,10 +364,10 @@
 		hpi = &internal_config.hugepage_info[num_sizes];
 		hpi->hugepage_sz =
 			rte_str_to_size(&dirent->d_name[dirent_start_len]);
-		hugedir = get_hugepage_dir(hpi->hugepage_sz);
 
 		/* first, check if we have a mountpoint */
-		if (hugedir == NULL) {
+		if (get_hugepage_dir(hpi->hugepage_sz,
+			hpi->hugedir, sizeof(hpi->hugedir)) < 0) {
 			uint32_t num_pages;
 
 			num_pages = get_num_hugepages(dirent->d_name);
@@ -378,7 +379,6 @@
 					num_pages, hpi->hugepage_sz);
 			continue;
 		}
-		snprintf(hpi->hugedir, sizeof(hpi->hugedir), "%s", hugedir);
 
 		/* try to obtain a writelock */
 		hpi->lock_descriptor = open(hpi->hugedir, O_RDONLY);
diff --git a/lib/librte_eal/linuxapp/eal/eal_memory.c b/lib/librte_eal/linuxapp/eal/eal_memory.c
index b7a2e95..fadc1de 100644
--- a/lib/librte_eal/linuxapp/eal/eal_memory.c
+++ b/lib/librte_eal/linuxapp/eal/eal_memory.c
@@ -1160,8 +1160,8 @@ void numa_error(char *where)
 	for (socket = 0; socket < RTE_MAX_NUMA_NODES && total_mem != 0; socket++) {
 		/* skips if the memory on specific socket wasn't requested */
 		for (i = 0; i < num_hp_info && memory[socket] != 0; i++){
-			snprintf(hp_used[i].hugedir, sizeof(hp_used[i].hugedir),
-					"%s", hp_info[i].hugedir);
+			strlcpy(hp_used[i].hugedir, hp_info[i].hugedir,
+				sizeof(hp_used[i].hugedir));
 			hp_used[i].num_pages[socket] = RTE_MIN(
 					memory[socket] / hp_info[i].hugepage_sz,
 					hp_info[i].num_pages[socket]);
-- 
1.7.1