4.9-stable review patch. If anyone has any objections, please let me know.
------------------
From: Eric Dumazet <edumazet@xxxxxxxxxx>
[ Upstream commit e70ac171658679ecf6bea4bbd9e9325cd6079d2b ]
tcp_rcv_established() can now run in process context.
We need to disable BH while acquiring tcp probe spinlock,
or risk a deadlock.
Fixes: 5413d1babe8f ("net: do not block BH while processing socket backlog")
Signed-off-by: Eric Dumazet <edumazet@xxxxxxxxxx>
Reported-by: Ricardo Nabinger Sanchez <rnsanchez@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/ipv4/tcp_probe.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
--- a/net/ipv4/tcp_probe.c
+++ b/net/ipv4/tcp_probe.c
@@ -117,7 +117,7 @@ static void jtcp_rcv_established(struct
(fwmark > 0 && skb->mark == fwmark)) &&
(full || tp->snd_cwnd != tcp_probe.lastcwnd)) {
- spin_lock(&tcp_probe.lock);
+ spin_lock_bh(&tcp_probe.lock);
/* If log fills, just silently drop */
if (tcp_probe_avail() > 1) {
struct tcp_log *p = tcp_probe.log + tcp_probe.head;
@@ -157,7 +157,7 @@ static void jtcp_rcv_established(struct
tcp_probe.head = (tcp_probe.head + 1) & (bufsize - 1);
}
tcp_probe.lastcwnd = tp->snd_cwnd;
- spin_unlock(&tcp_probe.lock);
+ spin_unlock_bh(&tcp_probe.lock);
wake_up(&tcp_probe.wait);
}