[3.8.y.z extended stable] Patch "inet: fix possible seqlock deadlocks" has been added to staging queue

[Kamal Mostafa]

This is a note to let you know that I have just added a patch titled

    inet: fix possible seqlock deadlocks

to the linux-3.8.y-queue branch of the 3.8.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.8.y-queue

This patch is scheduled to be released in version 3.8.13.15.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.8.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

>From 0949be1b9239355eec12d28ae20ab1c6976f3c34 Mon Sep 17 00:00:00 2001
From: Eric Dumazet <edumazet at google.com>
Date: Thu, 28 Nov 2013 09:51:22 -0800
Subject: inet: fix possible seqlock deadlocks

[ Upstream commit f1d8cba61c3c4b1eb88e507249c4cb8d635d9a76 ]

In commit c9e9042994d3 ("ipv4: fix possible seqlock deadlock") I left
another places where IP_INC_STATS_BH() were improperly used.

udp_sendmsg(), ping_v4_sendmsg() and tcp_v4_connect() are called from
process context, not from softirq context.

This was detected by lockdep seqlock support.

Reported-by: jongman heo <jongman.heo at samsung.com>
Fixes: 584bdf8cbdf6 ("[IPV4]: Fix "ipOutNoRoutes" counter error for TCP and UDP")
Fixes: c319b4d76b9e ("net: ipv4: add IPPROTO_ICMP socket kind")
Signed-off-by: Eric Dumazet <edumazet at google.com>
Cc: Hannes Frederic Sowa <hannes at stressinduktion.org>
Acked-by: Hannes Frederic Sowa <hannes at stressinduktion.org>
Signed-off-by: David S. Miller <davem at davemloft.net>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 net/ipv4/ping.c     | 2 +-
 net/ipv4/tcp_ipv4.c | 2 +-
 net/ipv4/udp.c      | 2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/net/ipv4/ping.c b/net/ipv4/ping.c
index eeaf513..3d8ddd9 100644
--- a/net/ipv4/ping.c
+++ b/net/ipv4/ping.c
@@ -571,7 +571,7 @@ static int ping_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
 		err = PTR_ERR(rt);
 		rt = NULL;
 		if (err == -ENETUNREACH)
-			IP_INC_STATS_BH(net, IPSTATS_MIB_OUTNOROUTES);
+			IP_INC_STATS(net, IPSTATS_MIB_OUTNOROUTES);
 		goto out;
 	}

diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 47b459a..94b273c 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -176,7 +176,7 @@ int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
 	if (IS_ERR(rt)) {
 		err = PTR_ERR(rt);
 		if (err == -ENETUNREACH)
-			IP_INC_STATS_BH(sock_net(sk), IPSTATS_MIB_OUTNOROUTES);
+			IP_INC_STATS(sock_net(sk), IPSTATS_MIB_OUTNOROUTES);
 		return err;
 	}

diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 9de5641..f982418 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -946,7 +946,7 @@ int udp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
 			err = PTR_ERR(rt);
 			rt = NULL;
 			if (err == -ENETUNREACH)
-				IP_INC_STATS_BH(net, IPSTATS_MIB_OUTNOROUTES);
+				IP_INC_STATS(net, IPSTATS_MIB_OUTNOROUTES);
 			goto out;
 		}

--
1.8.3.2