[for-next][PATCH 09/11] recordmcount: Fix memory leaks in the uwrite function

Steven Rostedt posted 11 patches 2 years, 9 months ago
[for-next][PATCH 09/11] recordmcount: Fix memory leaks in the uwrite function
Posted by Steven Rostedt 2 years, 9 months ago
From: Hao Zeng <zenghao@kylinos.cn>

Common realloc mistake: 'file_append' nulled but not freed upon failure

Link: https://lkml.kernel.org/r/20230426010527.703093-1-zenghao@kylinos.cn

Signed-off-by: Hao Zeng <zenghao@kylinos.cn>
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
---
 scripts/recordmcount.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/scripts/recordmcount.c b/scripts/recordmcount.c
index e30216525325..40ae6b2c7a6d 100644
--- a/scripts/recordmcount.c
+++ b/scripts/recordmcount.c
@@ -110,6 +110,7 @@ static ssize_t uwrite(void const *const buf, size_t const count)
 {
 	size_t cnt = count;
 	off_t idx = 0;
+	void *p = NULL;
 
 	file_updated = 1;
 
@@ -117,7 +118,10 @@ static ssize_t uwrite(void const *const buf, size_t const count)
 		off_t aoffset = (file_ptr + count) - file_end;
 
 		if (aoffset > file_append_size) {
-			file_append = realloc(file_append, aoffset);
+			p = realloc(file_append, aoffset);
+			if (!p)
+				free(file_append);
+			file_append = p;
 			file_append_size = aoffset;
 		}
 		if (!file_append) {
-- 
2.39.2