fix bug introduced with fixing path_check_prereq()

This fixes a bug introduced with:

commit 74c36329c3531acf59d76a09cd0c4cf11ce6b6a0
Author: Antony Pavlov <antonynpavlov@gmail.com>
Date:   Tue Oct 18 13:48:44 2011 +0400

    fs: fix path_check_prereq()

    This patch makes impossible the situations than path_check_prereq() can make
    'return 0' without changing errno.

    Signed-off-by: Antony Pavlov <antonynpavlov@gmail.com>
    Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

path_check_prereq is supposed to return 0 when a file does
not exist and S_UB_DOES_NOT_EXIST is given. stat() changes
errno, so we have to set errno back to 0 before returning.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

1 files changed, 6 insertions, 2 deletions

diff --git a/fs/fs.c b/fs/fs.c
index f42ca36078..51a7411b69 100644
--- a/fs/fs.c
+++ b/fs/fs.c
@@ -296,8 +296,10 @@ static int path_check_prereq(const char *path, unsigned int flags)
 	errno = 0;
 
 	if (stat(path, &s)) {
-		if (flags & S_UB_DOES_NOT_EXIST)
+		if (flags & S_UB_DOES_NOT_EXIST) {
+			errno = 0;
 			goto out;
+		}
 		errno = -ENOENT;
 		goto out;
 	}
@@ -307,8 +309,10 @@ static int path_check_prereq(const char *path, unsigned int flags)
 		goto out;
 	}
 
-	if (flags == S_UB_EXISTS)
+	if (flags == S_UB_EXISTS) {
+		errno = 0;
 		goto out;
+	}
 
 	m = s.st_mode;