[PATCH] tools: hv: kvp: fix memory leak in realloc failure handling

From: Kuan-Wei Chiu
Date: Sun Sep 24 2023 - 02:09:59 EST


In the previous code, there was a memory leak issue where the
previously allocated memory was not freed upon a failed realloc
operation. This patch addresses the problem by releasing the old memory
before setting the pointer to NULL in case of a realloc failure. This
ensures that memory is properly managed and avoids potential memory
leaks.

Signed-off-by: Kuan-Wei Chiu <visitorckw@xxxxxxxxx>
---
tools/hv/hv_kvp_daemon.c | 16 +++++++++++-----
1 file changed, 11 insertions(+), 5 deletions(-)

diff --git a/tools/hv/hv_kvp_daemon.c b/tools/hv/hv_kvp_daemon.c
index 27f5e7dfc2f7..af180278d56d 100644
--- a/tools/hv/hv_kvp_daemon.c
+++ b/tools/hv/hv_kvp_daemon.c
@@ -209,11 +209,13 @@ static void kvp_update_mem_state(int pool)
* We have more data to read.
*/
num_blocks++;
- record = realloc(record, alloc_unit * num_blocks);
+ struct kvp_record *record_tmp =
+ realloc(record, alloc_unit * num_blocks);

- if (record == NULL) {
+ if (record_tmp == NULL) {
syslog(LOG_ERR, "malloc failed");
kvp_release_lock(pool);
+ free(record);
exit(EXIT_FAILURE);
}
continue;
@@ -345,11 +347,15 @@ static int kvp_key_add_or_modify(int pool, const __u8 *key, int key_size,
*/
if (num_records == (ENTRIES_PER_BLOCK * num_blocks)) {
/* Need to allocate a larger array for reg entries. */
- record = realloc(record, sizeof(struct kvp_record) *
- ENTRIES_PER_BLOCK * (num_blocks + 1));
+ struct kvp_record *record_tmp = realloc(
+ record, sizeof(struct kvp_record) * ENTRIES_PER_BLOCK *
+ (num_blocks + 1));

- if (record == NULL)
+ if (record_tmp == NULL) {
+ free(record);
return 1;
+ }
+ record = record_tmp;
kvp_file_info[pool].num_blocks++;

}
--
2.25.1