| From foo@baz Thu Jun 29 19:45:34 CEST 2017 |
| From: WANG Cong <xiyou.wangcong@gmail.com> |
| Date: Tue, 20 Jun 2017 10:46:27 -0700 |
| Subject: igmp: add a missing spin_lock_init() |
| |
| From: WANG Cong <xiyou.wangcong@gmail.com> |
| |
| |
| [ 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 <andreyknvl@google.com> |
| Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> |
| Signed-off-by: David S. Miller <davem@davemloft.net> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| net/ipv4/igmp.c | 1 + |
| 1 file changed, 1 insertion(+) |
| |
| --- a/net/ipv4/igmp.c |
| +++ b/net/ipv4/igmp.c |
| @@ -1080,6 +1080,7 @@ static void igmpv3_add_delrec(struct in_ |
| 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); |
