[v2,13/21] trace-cmd library: Fix possible memory leak in read_and_parse_cmdlines()

Commit Message

Tzvetomir Stoyanov (VMware) Sept. 13, 2021, 12:27 p.m. UTC

Some error paths in read_and_parse_cmdlines() may lead to a memory leak.
Improved the error handling of this internal function to avoid it.

Signed-off-by: Tzvetomir Stoyanov (VMware) <[e-mail]>
---
 lib/trace-cmd/trace-input.c | 20 +++++++++++++-------
 1 file changed, 13 insertions(+), 7 deletions(-)

Patch

diff --git a/lib/trace-cmd/trace-input.c b/lib/trace-cmd/trace-input.c
index 60d75d47..9fd7e6e8 100644
--- a/lib/trace-cmd/trace-input.c
+++ b/lib/trace-cmd/trace-input.c
@@ -2999,20 +2999,26 @@  static int read_and_parse_cmdlines(struct tracecmd_input *handle)
 {
 	struct tep_handle *pevent = handle->pevent;
 	unsigned long long size;
-	char *cmdlines;
+	char *cmdlines = NULL;
+	int ret;
 
 	if (handle->file_state >= TRACECMD_FILE_CMD_LINES)
 		return 0;
 
-	if (read_data_and_size(handle, &cmdlines, &size) < 0)
-		return -1;
+	ret = read_data_and_size(handle, &cmdlines, &size);
+	if (ret < 0)
+		goto out;
+	if (!size) {
+		handle->file_state = TRACECMD_FILE_CMD_LINES;
+		goto out;
+	}
 	cmdlines[size] = 0;
 	tep_parse_saved_cmdlines(pevent, cmdlines);
-	free(cmdlines);
-
 	handle->file_state = TRACECMD_FILE_CMD_LINES;
-
-	return 0;
+	ret = 0;
+out:
+	free(cmdlines);
+	return ret;
 }
 
 static void extract_trace_clock(struct tracecmd_input *handle, char *line)