uftrace: Fix segfault when using --logfile

This patch is to fix segfault in --logfile. If logfd is NULL, set logfd to stderr before calling pr_err(). Fixed: #853 Signed-off-by: MinJeong Kim <[email protected]>
namhyung · Sep 9, 2019 · 371ea19 · 371ea19
1 parent 66eb586
commit 371ea19
Showing 1 changed file with 3 additions and 1 deletion.
diff --git a/uftrace.c b/uftrace.c
@@ -1082,8 +1082,10 @@ int main(int argc, char *argv[])
 
 	if (opts.logfile) {
 		logfp = fopen(opts.logfile, "a");
-		if (logfp == NULL)
+		if (logfp == NULL) {
+			logfp = stderr;
 			pr_err("cannot open log file");
+		}
 
 		setvbuf(logfp, NULL, _IOLBF, 1024);
 	}