From: Karel Zak <kzak@redhat.com>
Date: Tue, 6 Aug 2013 08:29:04 +0000 (+0200)
Subject: blkdiscard: use fstat() rather than stat() [coverity scan]
X-Git-Tag: v2.24-rc1~398
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=777519226d033fdea9bcad043c01aa6539c8b71d;p=thirdparty%2Futil-linux.git

blkdiscard: use fstat() rather than stat() [coverity scan]

 Calling function "open(char const *, int, ...)" that uses "path" after
 a check function. This can cause a time-of-check, time-of-use race
 condition.

.. well, in blkdiscard context it's mostly cosmetic change.

Signed-off-by: Karel Zak <kzak@redhat.com>
---

diff --git a/sys-utils/blkdiscard.c b/sys-utils/blkdiscard.c
index 0e15c01b08..af9ed66305 100644
--- a/sys-utils/blkdiscard.c
+++ b/sys-utils/blkdiscard.c
@@ -130,18 +130,17 @@ int main(int argc, char **argv)
 		usage(stderr);
 	}
 
-	if (stat(path, &sb) == -1)
-		err(EXIT_FAILURE, _("stat failed %s"), path);
-	if (!S_ISBLK(sb.st_mode))
-		errx(EXIT_FAILURE, _("%s: not a block device"), path);
-
 	fd = open(path, O_WRONLY);
 	if (fd < 0)
 		err(EXIT_FAILURE, _("cannot open %s"), path);
 
+	if (fstat(fd, &sb) == -1)
+		err(EXIT_FAILURE, _("stat failed %s"), path);
+	if (!S_ISBLK(sb.st_mode))
+		errx(EXIT_FAILURE, _("%s: not a block device"), path);
+
 	if (ioctl(fd, BLKGETSIZE64, &blksize))
 		err(EXIT_FAILURE, _("%s: BLKGETSIZE64 ioctl failed"), path);
-
 	if (ioctl(fd, BLKSSZGET, &secsize))
 		err(EXIT_FAILURE, _("%s: BLKSSZGET ioctl failed"), path);