linux-kernel - [PATCH] utimensat: AT_EMPTY

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <20181107091552.17100-1-mszeredi@redhat.com>
Date:   Wed,  7 Nov 2018 10:15:52 +0100
From:   Miklos Szeredi <mszeredi@...hat.com>
To:     Al Viro <viro@...iv.linux.org.uk>
Cc:     Vivek Goyal <vgoyal@...hat.com>, linux-fsdevel@...r.kernel.org,
        linux-kernel@...r.kernel.org
Subject: [PATCH] utimensat: AT_EMPTY_PATH support

This makes it possible to use utimensat on an O_PATH file (including
symlinks).

It supersedes the nonstandard utimensat(fd, NULL, ...) form.

Signed-off-by: Miklos Szeredi <mszeredi@...hat.com>
---
 fs/utimes.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/fs/utimes.c b/fs/utimes.c
index bdcf2daf39c1..f9c7ebad19d7 100644
--- a/fs/utimes.c
+++ b/fs/utimes.c
@@ -97,13 +97,13 @@ long do_utimes(int dfd, const char __user *filename, struct timespec64 *times,
 		goto out;
 	}
 
-	if (flags & ~AT_SYMLINK_NOFOLLOW)
+	if (flags & ~(AT_SYMLINK_NOFOLLOW | AT_EMPTY_PATH))
 		goto out;
 
 	if (filename == NULL && dfd != AT_FDCWD) {
 		struct fd f;
 
-		if (flags & AT_SYMLINK_NOFOLLOW)
+		if (flags)
 			goto out;
 
 		f = fdget(dfd);
@@ -119,6 +119,8 @@ long do_utimes(int dfd, const char __user *filename, struct timespec64 *times,
 
 		if (!(flags & AT_SYMLINK_NOFOLLOW))
 			lookup_flags |= LOOKUP_FOLLOW;
+		if (flags & AT_EMPTY_PATH)
+			lookup_flags |= LOOKUP_EMPTY;
 retry:
 		error = user_path_at(dfd, filename, lookup_flags, &path);
 		if (error)
-- 
2.14.3