linux-kernel - [PATCH 6/9] sysfs: use check_submounts_and

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

Date:	Thu,  8 Aug 2013 17:24:47 +0200
From:	Miklos Szeredi <miklos@...redi.hu>
To:	rwheeler@...hat.com, avati@...hat.com, viro@...IV.linux.org.uk
Cc:	bfoster@...hat.com, dhowells@...hat.com, eparis@...hat.com,
	linux-fsdevel@...r.kernel.org, linux-kernel@...r.kernel.org,
	mszeredi@...e.cz
Subject: [PATCH 6/9] sysfs: use check_submounts_and_drop()

From: Miklos Szeredi <mszeredi@...e.cz>

Do have_submounts(), shrink_dcache_parent() and d_drop() atomically.

check_submounts_and_drop() can deal with negative dentries and
non-directories as well.

Non-directories can also be mounted on.  And just like directories we don't
want these to disappear with invalidation.

Signed-off-by: Miklos Szeredi <mszeredi@...e.cz>
---
 fs/sysfs/dir.c | 20 ++++++++------------
 1 file changed, 8 insertions(+), 12 deletions(-)

diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c
index e068e74..fde8856 100644
--- a/fs/sysfs/dir.c
+++ b/fs/sysfs/dir.c
@@ -297,7 +297,6 @@ static int sysfs_dentry_delete(const struct dentry *dentry)
 static int sysfs_dentry_revalidate(struct dentry *dentry, unsigned int flags)
 {
 	struct sysfs_dirent *sd;
-	int is_dir;
 	int type;
 
 	if (flags & LOOKUP_RCU)
@@ -341,18 +340,15 @@ out_bad:
 	 * is performed at its new name the dentry will be readded
 	 * to the dcache hashes.
 	 */
-	is_dir = (sysfs_type(sd) == SYSFS_DIR);
 	mutex_unlock(&sysfs_mutex);
-	if (is_dir) {
-		/* If we have submounts we must allow the vfs caches
-		 * to lie about the state of the filesystem to prevent
-		 * leaks and other nasty things.
-		 */
-		if (have_submounts(dentry))
-			goto out_valid;
-		shrink_dcache_parent(dentry);
-	}
-	d_drop(dentry);
+
+	/* If we have submounts we must allow the vfs caches
+	 * to lie about the state of the filesystem to prevent
+	 * leaks and other nasty things.
+	 */
+	if (check_submounts_and_drop(dentry) != 0)
+		goto out_valid;
+
 	return 0;
 }
 
-- 
1.8.1.4

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/