[PATCH v5 2/3] tools/mm/page_owner_sort: free per-record allocations

[Yichong Chen]

add_list() allocates comm and txt for each page owner record, but the
cleanup path only frees the outer list array. This leaks both buffers for
every retained record.

Free partial allocations in add_list(), discarded records during
culling, and retained records on exit.

Reviewed-by: Vishal Moola <vishal.moola@xxxxxxxxx>
Signed-off-by: Yichong Chen <chenyichong@xxxxxxxxxxxxx>
---
 tools/mm/page_owner_sort.c | 20 ++++++++++++++++++--
 1 file changed, 18 insertions(+), 2 deletions(-)

diff --git a/tools/mm/page_owner_sort.c b/tools/mm/page_owner_sort.c
index 3c754826cec5..4c9be28abe3b 100644
--- a/tools/mm/page_owner_sort.c
+++ b/tools/mm/page_owner_sort.c
@@ -396,6 +396,12 @@ static char *get_comm(char *buf)
 	return comm_str;
 }
 
+static void free_block_list(struct block_list *block)
+{
+	free(block->comm);
+	free(block->txt);
+}
+
 static int get_arg_type(const char *arg)
 {
 	if (!strcmp(arg, "pid") || !strcmp(arg, "p"))
@@ -502,9 +508,14 @@ static bool add_list(char *buf, int len, char *ext_buf)
 	list[list_size].pid = get_pid(buf);
 	list[list_size].tgid = get_tgid(buf);
 	list[list_size].comm = get_comm(buf);
-	list[list_size].txt = malloc(len+1);
+	if (!list[list_size].comm) {
+		fprintf(stderr, "Out of memory\n");
+		return false;
+	}
+	list[list_size].txt = malloc(len + 1);
 	if (!list[list_size].txt) {
 		fprintf(stderr, "Out of memory\n");
+		free(list[list_size].comm);
 		return false;
 	}
 	memcpy(list[list_size].txt, buf, len);
@@ -863,8 +874,10 @@ int main(int argc, char **argv)
 		} else {
 			list[count-1].num += list[i].num;
 			list[count-1].page_num += list[i].page_num;
+			free_block_list(&list[i]);
 		}
 	}
+	list_size = count;
 
 	qsort(list, count, sizeof(list[0]), compare_sort_condition);
 
@@ -898,8 +911,11 @@ int main(int argc, char **argv)
 		free(ext_buf);
 	if (buf)
 		free(buf);
-	if (list)
+	if (list) {
+		for (i = 0; i < list_size; i++)
+			free_block_list(&list[i]);
 		free(list);
+	}
 out_ts:
 	regfree(&ts_nsec_pattern);
 out_comm:
-- 
2.51.0