From cac2a9bb4034f2395bdbe1ad2bd3f29a470e14f0 Mon Sep 17 00:00:00 2001 From: WANG Cong Date: Tue, 20 Jun 2017 10:46:27 -0700 Subject: [PATCH] igmp: add a missing spin_lock_init() [ Upstream commit b4846fc3c8559649277e3e4e6b5cec5348a8d208 ] Andrey reported a lockdep warning on non-initialized spinlock: INFO: trying to register non-static key. the code is fine but needs lockdep annotation. turning off the locking correctness validator. CPU: 1 PID: 4099 Comm: a.out Not tainted 4.12.0-rc6+ #9 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:16 dump_stack+0x292/0x395 lib/dump_stack.c:52 register_lock_class+0x717/0x1aa0 kernel/locking/lockdep.c:755 ? 0xffffffffa0000000 __lock_acquire+0x269/0x3690 kernel/locking/lockdep.c:3255 lock_acquire+0x22d/0x560 kernel/locking/lockdep.c:3855 __raw_spin_lock_bh ./include/linux/spinlock_api_smp.h:135 _raw_spin_lock_bh+0x36/0x50 kernel/locking/spinlock.c:175 spin_lock_bh ./include/linux/spinlock.h:304 ip_mc_clear_src+0x27/0x1e0 net/ipv4/igmp.c:2076 igmpv3_clear_delrec+0xee/0x4f0 net/ipv4/igmp.c:1194 ip_mc_destroy_dev+0x4e/0x190 net/ipv4/igmp.c:1736 We miss a spin_lock_init() in igmpv3_add_delrec(), probably because previously we never use it on this code path. Since we already unlink it from the global mc_tomb list, it is probably safe not to acquire this spinlock here. It does not harm to have it although, to avoid conditional locking. Fixes: c38b7d327aaf ("igmp: acquire pmc lock for ip_mc_clear_src()") Reported-by: Andrey Konovalov Signed-off-by: Cong Wang Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/ipv4/igmp.c | 1 + 1 file changed, 1 insertion(+) diff --git a/net/ipv4/igmp.c b/net/ipv4/igmp.c index 8520eff4a5cc..19930da56b0a 100644 --- a/net/ipv4/igmp.c +++ b/net/ipv4/igmp.c @@ -1112,6 +1112,7 @@ static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im) pmc = kzalloc(sizeof(*pmc), GFP_KERNEL); if (!pmc) return; + spin_lock_init(&pmc->lock); spin_lock_bh(&im->lock); pmc->interface = im->interface; in_dev_hold(in_dev); -- 2.11.4.GIT