From: Dave Jones <davej@redhat.com>
To: netdev@vger.kernel.org
Cc: Linux Kernel <linux-kernel@vger.kernel.org>
Subject: fix locking unbalance in irda_sendmsg
Date: Tue, 12 Apr 2011 18:12:55 -0400 [thread overview]
Message-ID: <20110412221254.GA23906@redhat.com> (raw)
5b40964eadea40509d353318d2c82e8b7bf5e8a5 introduced a path where
we have a locking unbalance. If we pass invalid flags, we unlock
a socket we never locked, resulting in this...
=====================================
[ BUG: bad unlock balance detected! ]
-------------------------------------
trinity/20101 is trying to release lock (sk_lock-AF_IRDA) at:
[<ffffffffa057f001>] irda_sendmsg+0x207/0x21d [irda]
but there are no more locks to release!
other info that might help us debug this:
no locks held by trinity/20101.
stack backtrace:
Pid: 20101, comm: trinity Not tainted 2.6.39-rc3+ #3
Call Trace:
[<ffffffffa057f001>] ? irda_sendmsg+0x207/0x21d [irda]
[<ffffffff81085041>] print_unlock_inbalance_bug+0xc7/0xd2
[<ffffffffa057f001>] ? irda_sendmsg+0x207/0x21d [irda]
[<ffffffff81086aca>] lock_release+0xcf/0x18e
[<ffffffff813ed190>] release_sock+0x2d/0x155
[<ffffffffa057f001>] irda_sendmsg+0x207/0x21d [irda]
[<ffffffff813e9f8c>] __sock_sendmsg+0x69/0x75
[<ffffffff813ea105>] sock_sendmsg+0xa1/0xb6
[<ffffffff81100ca3>] ? might_fault+0x5c/0xac
[<ffffffff81086b7c>] ? lock_release+0x181/0x18e
[<ffffffff81100cec>] ? might_fault+0xa5/0xac
[<ffffffff81100ca3>] ? might_fault+0x5c/0xac
[<ffffffff81133b94>] ? fcheck_files+0xb9/0xf0
[<ffffffff813f387a>] ? copy_from_user+0x2f/0x31
[<ffffffff813f3b70>] ? verify_iovec+0x52/0xa6
[<ffffffff813eb4e3>] sys_sendmsg+0x23a/0x2b8
[<ffffffff81086b7c>] ? lock_release+0x181/0x18e
[<ffffffff810773c6>] ? up_read+0x28/0x2c
[<ffffffff814bec3d>] ? do_page_fault+0x360/0x3b4
[<ffffffff81087043>] ? trace_hardirqs_on_caller+0x10b/0x12f
[<ffffffff810458aa>] ? finish_task_switch+0xb2/0xe3
[<ffffffff8104583e>] ? finish_task_switch+0x46/0xe3
[<ffffffff8108364a>] ? trace_hardirqs_off_caller+0x33/0x90
[<ffffffff814bbaf9>] ? retint_swapgs+0x13/0x1b
[<ffffffff81087043>] ? trace_hardirqs_on_caller+0x10b/0x12f
[<ffffffff810a9dd3>] ? audit_syscall_entry+0x11c/0x148
[<ffffffff8125609e>] ? trace_hardirqs_on_thunk+0x3a/0x3f
[<ffffffff814c22c2>] system_call_fastpath+0x16/0x1b
Signed-off-by: Dave Jones <davej@redhat.com>
diff --git a/net/irda/af_irda.c b/net/irda/af_irda.c
index c9890e2..cc61697 100644
--- a/net/irda/af_irda.c
+++ b/net/irda/af_irda.c
@@ -1297,8 +1297,7 @@ static int irda_sendmsg(struct kiocb *iocb, struct socket *sock,
/* Note : socket.c set MSG_EOR on SEQPACKET sockets */
if (msg->msg_flags & ~(MSG_DONTWAIT | MSG_EOR | MSG_CMSG_COMPAT |
MSG_NOSIGNAL)) {
- err = -EINVAL;
- goto out;
+ return -EINVAL;
}
lock_sock(sk);
next reply other threads:[~2011-04-12 22:12 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-04-12 22:12 Dave Jones [this message]
2011-04-12 22:30 ` fix locking unbalance in irda_sendmsg David Miller
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20110412221254.GA23906@redhat.com \
--to=davej@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=netdev@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.