From: Jens Axboe <axboe@fb.com>
Date: Mon, 14 Apr 2014 17:36:01 +0000 (-0600)
Subject: backend: better NULL termination fix for IO scheduler switching
X-Git-Tag: fio-2.1.9~41
X-Git-Url: https://git.kernel.dk/?p=fio.git;a=commitdiff_plain;h=49c6f33d1739f96c16a0ab54cde3dc4ef64b90e9

backend: better NULL termination fix for IO scheduler switching

Signed-off-by: Jens Axboe <axboe@fb.com>
---

diff --git a/backend.c b/backend.c
index c1c8f967..62bca291 100644
--- a/backend.c
+++ b/backend.c
@@ -1114,13 +1114,14 @@ static int switch_ioscheduler(struct thread_data *td)
 	/*
 	 * Read back and check that the selected scheduler is now the default.
 	 */
-	memset(tmp, 0, sizeof(tmp));
-	ret = fread(tmp, 1, sizeof(tmp) - 1, f);
+	ret = fread(tmp, sizeof(tmp), 1, f);
 	if (ferror(f) || ret < 0) {
 		td_verror(td, errno, "fread");
 		fclose(f);
 		return 1;
 	}
+	tmp[sizeof(tmp) - 1] = '\0';
+
 
 	sprintf(tmp2, "[%s]", td->o.ioscheduler);
 	if (!strstr(tmp, tmp2)) {