linux-kernel - [PATCH v2 06/14] locks: don't walk inode->i_flock list in locks

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:	Tue, 11 Jun 2013 07:09:00 -0400
From:	Jeff Layton <jlayton@...hat.com>
To:	viro@...iv.linux.org.uk, matthew@....cx, bfields@...ldses.org
Cc:	dhowells@...hat.com, sage@...tank.com, smfrench@...il.com,
	swhiteho@...hat.com, Trond.Myklebust@...app.com,
	akpm@...ux-foundation.org, linux-kernel@...r.kernel.org,
	linux-afs@...ts.infradead.org, ceph-devel@...r.kernel.org,
	linux-cifs@...r.kernel.org, samba-technical@...ts.samba.org,
	cluster-devel@...hat.com, linux-nfs@...r.kernel.org,
	linux-fsdevel@...r.kernel.org, piastryyy@...il.com
Subject: [PATCH v2 06/14] locks: don't walk inode->i_flock list in locks_show

When we convert over to using the i_lock to protect the i_flock list,
that will introduce a potential lock inversion problem in locks_show.
When we want to walk the i_flock list, we'll need to take the i_lock.

Rather than do that, just walk the global blocked_locks list and print
out any that are blocked on the given lock.

Signed-off-by: Jeff Layton <jlayton@...hat.com>
---
 fs/locks.c |    6 ++++--
 1 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/fs/locks.c b/fs/locks.c
index e451d18..3fd27f0 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -2249,8 +2249,10 @@ static int locks_show(struct seq_file *f, void *v)
 
 	lock_get_status(f, fl, *((loff_t *)f->private), "");
 
-	list_for_each_entry(bfl, &fl->fl_block, fl_block)
-		lock_get_status(f, bfl, *((loff_t *)f->private), " ->");
+	list_for_each_entry(bfl, &blocked_list, fl_link) {
+		if (bfl->fl_next == fl)
+			lock_get_status(f, bfl, *((loff_t *)f->private), " ->");
+	}
 
 	return 0;
 }
-- 
1.7.1

--
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/