Message ID | CAM_iQpX=Vb-0xMjwOrriYcG38GT+U9zknggVbCb0_pBUh1NMkQ@mail.gmail.com |
---|---|
State | RFC, archived |
Delegated to: | David Miller |
Headers | show |
On Wed, Mar 1, 2017 at 6:18 PM, Cong Wang <xiyou.wangcong@gmail.com> wrote: > On Wed, Mar 1, 2017 at 2:44 AM, Dmitry Vyukov <dvyukov@google.com> wrote: >> Hello, >> >> I've got the following deadlock report while running syzkaller fuzzer >> on linux-next/51788aebe7cae79cb334ad50641347465fc188fd: >> >> ====================================================== >> [ INFO: possible circular locking dependency detected ] >> 4.10.0-next-20170301+ #1 Not tainted >> ------------------------------------------------------- >> syz-executor1/3394 is trying to acquire lock: >> (sk_lock-AF_INET){+.+.+.}, at: [<ffffffff838864cc>] lock_sock >> include/net/sock.h:1460 [inline] >> (sk_lock-AF_INET){+.+.+.}, at: [<ffffffff838864cc>] >> do_ip_setsockopt.isra.12+0x21c/0x3540 net/ipv4/ip_sockglue.c:652 >> >> but task is already holding lock: >> (rtnl_mutex){+.+.+.}, at: [<ffffffff836fbd97>] rtnl_lock+0x17/0x20 >> net/core/rtnetlink.c:70 >> >> which lock already depends on the new lock. >> >> >> the existing dependency chain (in reverse order) is: >> >> -> #1 (rtnl_mutex){+.+.+.}: >> validate_chain kernel/locking/lockdep.c:2265 [inline] >> __lock_acquire+0x2149/0x3430 kernel/locking/lockdep.c:3338 >> lock_acquire+0x2a1/0x630 kernel/locking/lockdep.c:3753 >> __mutex_lock_common kernel/locking/mutex.c:754 [inline] >> __mutex_lock+0x172/0x1730 kernel/locking/mutex.c:891 >> mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:906 >> rtnl_lock+0x17/0x20 net/core/rtnetlink.c:70 >> mrtsock_destruct+0x86/0x2c0 net/ipv4/ipmr.c:1281 >> ip_ra_control+0x459/0x600 net/ipv4/ip_sockglue.c:372 >> do_ip_setsockopt.isra.12+0x1064/0x3540 net/ipv4/ip_sockglue.c:1161 >> ip_setsockopt+0x3a/0xb0 net/ipv4/ip_sockglue.c:1264 >> raw_setsockopt+0xb7/0xd0 net/ipv4/raw.c:839 >> sock_common_setsockopt+0x95/0xd0 net/core/sock.c:2725 >> SYSC_setsockopt net/socket.c:1786 [inline] >> SyS_setsockopt+0x25c/0x390 net/socket.c:1765 >> entry_SYSCALL_64_fastpath+0x1f/0xc2 >> >> -> #0 (sk_lock-AF_INET){+.+.+.}: >> check_prev_add kernel/locking/lockdep.c:1828 [inline] >> check_prevs_add+0xa8f/0x19f0 kernel/locking/lockdep.c:1938 >> validate_chain kernel/locking/lockdep.c:2265 [inline] >> __lock_acquire+0x2149/0x3430 kernel/locking/lockdep.c:3338 >> lock_acquire+0x2a1/0x630 kernel/locking/lockdep.c:3753 >> lock_sock_nested+0xcb/0x120 net/core/sock.c:2530 >> lock_sock include/net/sock.h:1460 [inline] >> do_ip_setsockopt.isra.12+0x21c/0x3540 net/ipv4/ip_sockglue.c:652 >> ip_setsockopt+0x3a/0xb0 net/ipv4/ip_sockglue.c:1264 >> tcp_setsockopt+0x82/0xd0 net/ipv4/tcp.c:2721 >> sock_common_setsockopt+0x95/0xd0 net/core/sock.c:2725 >> SYSC_setsockopt net/socket.c:1786 [inline] >> SyS_setsockopt+0x25c/0x390 net/socket.c:1765 >> entry_SYSCALL_64_fastpath+0x1f/0xc2 >> > > Please try the attached patch (compile only). Pushed the patch to the bots. Thanks
On Thu, Mar 2, 2017 at 10:40 AM, Dmitry Vyukov <dvyukov@google.com> wrote: > On Wed, Mar 1, 2017 at 6:18 PM, Cong Wang <xiyou.wangcong@gmail.com> wrote: >> On Wed, Mar 1, 2017 at 2:44 AM, Dmitry Vyukov <dvyukov@google.com> wrote: >>> Hello, >>> >>> I've got the following deadlock report while running syzkaller fuzzer >>> on linux-next/51788aebe7cae79cb334ad50641347465fc188fd: >>> >>> ====================================================== >>> [ INFO: possible circular locking dependency detected ] >>> 4.10.0-next-20170301+ #1 Not tainted >>> ------------------------------------------------------- >>> syz-executor1/3394 is trying to acquire lock: >>> (sk_lock-AF_INET){+.+.+.}, at: [<ffffffff838864cc>] lock_sock >>> include/net/sock.h:1460 [inline] >>> (sk_lock-AF_INET){+.+.+.}, at: [<ffffffff838864cc>] >>> do_ip_setsockopt.isra.12+0x21c/0x3540 net/ipv4/ip_sockglue.c:652 >>> >>> but task is already holding lock: >>> (rtnl_mutex){+.+.+.}, at: [<ffffffff836fbd97>] rtnl_lock+0x17/0x20 >>> net/core/rtnetlink.c:70 >>> >>> which lock already depends on the new lock. >>> >>> >>> the existing dependency chain (in reverse order) is: >>> >>> -> #1 (rtnl_mutex){+.+.+.}: >>> validate_chain kernel/locking/lockdep.c:2265 [inline] >>> __lock_acquire+0x2149/0x3430 kernel/locking/lockdep.c:3338 >>> lock_acquire+0x2a1/0x630 kernel/locking/lockdep.c:3753 >>> __mutex_lock_common kernel/locking/mutex.c:754 [inline] >>> __mutex_lock+0x172/0x1730 kernel/locking/mutex.c:891 >>> mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:906 >>> rtnl_lock+0x17/0x20 net/core/rtnetlink.c:70 >>> mrtsock_destruct+0x86/0x2c0 net/ipv4/ipmr.c:1281 >>> ip_ra_control+0x459/0x600 net/ipv4/ip_sockglue.c:372 >>> do_ip_setsockopt.isra.12+0x1064/0x3540 net/ipv4/ip_sockglue.c:1161 >>> ip_setsockopt+0x3a/0xb0 net/ipv4/ip_sockglue.c:1264 >>> raw_setsockopt+0xb7/0xd0 net/ipv4/raw.c:839 >>> sock_common_setsockopt+0x95/0xd0 net/core/sock.c:2725 >>> SYSC_setsockopt net/socket.c:1786 [inline] >>> SyS_setsockopt+0x25c/0x390 net/socket.c:1765 >>> entry_SYSCALL_64_fastpath+0x1f/0xc2 >>> >>> -> #0 (sk_lock-AF_INET){+.+.+.}: >>> check_prev_add kernel/locking/lockdep.c:1828 [inline] >>> check_prevs_add+0xa8f/0x19f0 kernel/locking/lockdep.c:1938 >>> validate_chain kernel/locking/lockdep.c:2265 [inline] >>> __lock_acquire+0x2149/0x3430 kernel/locking/lockdep.c:3338 >>> lock_acquire+0x2a1/0x630 kernel/locking/lockdep.c:3753 >>> lock_sock_nested+0xcb/0x120 net/core/sock.c:2530 >>> lock_sock include/net/sock.h:1460 [inline] >>> do_ip_setsockopt.isra.12+0x21c/0x3540 net/ipv4/ip_sockglue.c:652 >>> ip_setsockopt+0x3a/0xb0 net/ipv4/ip_sockglue.c:1264 >>> tcp_setsockopt+0x82/0xd0 net/ipv4/tcp.c:2721 >>> sock_common_setsockopt+0x95/0xd0 net/core/sock.c:2725 >>> SYSC_setsockopt net/socket.c:1786 [inline] >>> SyS_setsockopt+0x25c/0x390 net/socket.c:1765 >>> entry_SYSCALL_64_fastpath+0x1f/0xc2 >>> >> >> Please try the attached patch (compile only). > > > Pushed the patch to the bots. > Thanks This patch triggers: [ 57.748990] RTNL: assertion failed at net/ipv4/ipmr.c (1236) [ 57.749022] CPU: 1 PID: 5301 Comm: syz-executor2 Not tainted 4.10.0+ #15 [ 57.749026] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 57.749028] Call Trace: [ 57.749042] dump_stack+0x2ee/0x3ef [ 57.749219] mrtsock_destruct+0x27e/0x2f0 [ 57.749241] ip_ra_control+0x459/0x600 [ 57.749287] raw_close+0x19/0x30 [ 57.749295] inet_release+0xed/0x1c0 [ 57.749303] sock_release+0x8d/0x1e0 [ 57.749316] sock_close+0x16/0x20 [ 57.749323] __fput+0x332/0x7f0 [ 57.749340] ____fput+0x15/0x20 [ 57.749347] task_work_run+0x18a/0x260 [ 57.749372] do_exit+0x18ef/0x28b0 [ 57.749641] do_group_exit+0x149/0x420 [ 57.749656] get_signal+0x7e0/0x1820 [ 57.749697] do_signal+0xd2/0x2190 [ 57.749746] exit_to_usermode_loop+0x200/0x2a0 [ 57.749758] syscall_return_slowpath+0x4d3/0x570 [ 57.749835] entry_SYSCALL_64_fastpath+0xc0/0xc2 [ 57.749840] RIP: 0033:0x44fb79 [ 57.749843] RSP: 002b:00007fbba84d9cf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca [ 57.749850] RAX: fffffffffffffe00 RBX: 0000000000708218 RCX: 000000000044fb79 [ 57.749854] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000708218 [ 57.749857] RBP: 00000000007081f8 R08: 0000000000000000 R09: 0000000000000000 [ 57.749860] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 57.749864] R13: 0000000000a5fc57 R14: 00007fbba84da9c0 R15: 000000000000000c [ 57.749964] [ 57.749966] =============================== [ 57.749967] [ INFO: suspicious RCU usage. ] [ 57.749971] 4.10.0+ #15 Not tainted [ 57.749972] ------------------------------- [ 57.749975] net/ipv4/ipmr.c:1238 suspicious rcu_dereference_protected() usage! [ 57.749977] [ 57.749977] other info that might help us debug this: [ 57.749977] [ 57.749980] [ 57.749980] rcu_scheduler_active = 2, debug_locks = 0 [ 57.749982] no locks held by syz-executor2/5301. [ 57.749984] [ 57.749984] stack backtrace: [ 57.749989] CPU: 1 PID: 5301 Comm: syz-executor2 Not tainted 4.10.0+ #15 [ 57.749993] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 57.749995] Call Trace: [ 57.750001] dump_stack+0x2ee/0x3ef [ 57.750117] lockdep_rcu_suspicious+0x139/0x180 [ 57.750122] mrtsock_destruct+0x167/0x2f0 [ 57.750144] ip_ra_control+0x459/0x600 [ 57.750182] raw_close+0x19/0x30 [ 57.750188] inet_release+0xed/0x1c0 [ 57.750194] sock_release+0x8d/0x1e0 [ 57.750208] sock_close+0x16/0x20 [ 57.750213] __fput+0x332/0x7f0 [ 57.750228] ____fput+0x15/0x20 [ 57.750233] task_work_run+0x18a/0x260 [ 57.750256] do_exit+0x18ef/0x28b0 [ 57.750499] do_group_exit+0x149/0x420 [ 57.750515] get_signal+0x7e0/0x1820 [ 57.750556] do_signal+0xd2/0x2190 [ 57.750604] exit_to_usermode_loop+0x200/0x2a0 [ 57.750616] syscall_return_slowpath+0x4d3/0x570 [ 57.750693] entry_SYSCALL_64_fastpath+0xc0/0xc2 [ 57.750698] RIP: 0033:0x44fb79 [ 57.750701] RSP: 002b:00007fbba84d9cf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca [ 57.750708] RAX: fffffffffffffe00 RBX: 0000000000708218 RCX: 000000000044fb79 [ 57.750712] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000708218 [ 57.750716] RBP: 00000000007081f8 R08: 0000000000000000 R09: 0000000000000000 [ 57.750720] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 57.750724] R13: 0000000000a5fc57 R14: 00007fbba84da9c0 R15: 000000000000000c
On Fri, Mar 3, 2017 at 7:43 PM, Dmitry Vyukov <dvyukov@google.com> wrote: > On Thu, Mar 2, 2017 at 10:40 AM, Dmitry Vyukov <dvyukov@google.com> wrote: >> On Wed, Mar 1, 2017 at 6:18 PM, Cong Wang <xiyou.wangcong@gmail.com> wrote: >>> On Wed, Mar 1, 2017 at 2:44 AM, Dmitry Vyukov <dvyukov@google.com> wrote: >>>> Hello, >>>> >>>> I've got the following deadlock report while running syzkaller fuzzer >>>> on linux-next/51788aebe7cae79cb334ad50641347465fc188fd: >>>> >>>> ====================================================== >>>> [ INFO: possible circular locking dependency detected ] >>>> 4.10.0-next-20170301+ #1 Not tainted >>>> ------------------------------------------------------- >>>> syz-executor1/3394 is trying to acquire lock: >>>> (sk_lock-AF_INET){+.+.+.}, at: [<ffffffff838864cc>] lock_sock >>>> include/net/sock.h:1460 [inline] >>>> (sk_lock-AF_INET){+.+.+.}, at: [<ffffffff838864cc>] >>>> do_ip_setsockopt.isra.12+0x21c/0x3540 net/ipv4/ip_sockglue.c:652 >>>> >>>> but task is already holding lock: >>>> (rtnl_mutex){+.+.+.}, at: [<ffffffff836fbd97>] rtnl_lock+0x17/0x20 >>>> net/core/rtnetlink.c:70 >>>> >>>> which lock already depends on the new lock. >>>> >>>> >>>> the existing dependency chain (in reverse order) is: >>>> >>>> -> #1 (rtnl_mutex){+.+.+.}: >>>> validate_chain kernel/locking/lockdep.c:2265 [inline] >>>> __lock_acquire+0x2149/0x3430 kernel/locking/lockdep.c:3338 >>>> lock_acquire+0x2a1/0x630 kernel/locking/lockdep.c:3753 >>>> __mutex_lock_common kernel/locking/mutex.c:754 [inline] >>>> __mutex_lock+0x172/0x1730 kernel/locking/mutex.c:891 >>>> mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:906 >>>> rtnl_lock+0x17/0x20 net/core/rtnetlink.c:70 >>>> mrtsock_destruct+0x86/0x2c0 net/ipv4/ipmr.c:1281 >>>> ip_ra_control+0x459/0x600 net/ipv4/ip_sockglue.c:372 >>>> do_ip_setsockopt.isra.12+0x1064/0x3540 net/ipv4/ip_sockglue.c:1161 >>>> ip_setsockopt+0x3a/0xb0 net/ipv4/ip_sockglue.c:1264 >>>> raw_setsockopt+0xb7/0xd0 net/ipv4/raw.c:839 >>>> sock_common_setsockopt+0x95/0xd0 net/core/sock.c:2725 >>>> SYSC_setsockopt net/socket.c:1786 [inline] >>>> SyS_setsockopt+0x25c/0x390 net/socket.c:1765 >>>> entry_SYSCALL_64_fastpath+0x1f/0xc2 >>>> >>>> -> #0 (sk_lock-AF_INET){+.+.+.}: >>>> check_prev_add kernel/locking/lockdep.c:1828 [inline] >>>> check_prevs_add+0xa8f/0x19f0 kernel/locking/lockdep.c:1938 >>>> validate_chain kernel/locking/lockdep.c:2265 [inline] >>>> __lock_acquire+0x2149/0x3430 kernel/locking/lockdep.c:3338 >>>> lock_acquire+0x2a1/0x630 kernel/locking/lockdep.c:3753 >>>> lock_sock_nested+0xcb/0x120 net/core/sock.c:2530 >>>> lock_sock include/net/sock.h:1460 [inline] >>>> do_ip_setsockopt.isra.12+0x21c/0x3540 net/ipv4/ip_sockglue.c:652 >>>> ip_setsockopt+0x3a/0xb0 net/ipv4/ip_sockglue.c:1264 >>>> tcp_setsockopt+0x82/0xd0 net/ipv4/tcp.c:2721 >>>> sock_common_setsockopt+0x95/0xd0 net/core/sock.c:2725 >>>> SYSC_setsockopt net/socket.c:1786 [inline] >>>> SyS_setsockopt+0x25c/0x390 net/socket.c:1765 >>>> entry_SYSCALL_64_fastpath+0x1f/0xc2 >>>> >>> >>> Please try the attached patch (compile only). >> >> >> Pushed the patch to the bots. >> Thanks > > > This patch triggers: > > [ 57.748990] RTNL: assertion failed at net/ipv4/ipmr.c (1236) > [ 57.749022] CPU: 1 PID: 5301 Comm: syz-executor2 Not tainted 4.10.0+ #15 > [ 57.749026] Hardware name: Google Google Compute Engine/Google > Compute Engine, BIOS Google 01/01/2011 > [ 57.749028] Call Trace: > [ 57.749042] dump_stack+0x2ee/0x3ef > [ 57.749219] mrtsock_destruct+0x27e/0x2f0 > [ 57.749241] ip_ra_control+0x459/0x600 > [ 57.749287] raw_close+0x19/0x30 > [ 57.749295] inet_release+0xed/0x1c0 > [ 57.749303] sock_release+0x8d/0x1e0 > [ 57.749316] sock_close+0x16/0x20 > [ 57.749323] __fput+0x332/0x7f0 > [ 57.749340] ____fput+0x15/0x20 > [ 57.749347] task_work_run+0x18a/0x260 > [ 57.749372] do_exit+0x18ef/0x28b0 > [ 57.749641] do_group_exit+0x149/0x420 > [ 57.749656] get_signal+0x7e0/0x1820 > [ 57.749697] do_signal+0xd2/0x2190 > [ 57.749746] exit_to_usermode_loop+0x200/0x2a0 > [ 57.749758] syscall_return_slowpath+0x4d3/0x570 > [ 57.749835] entry_SYSCALL_64_fastpath+0xc0/0xc2 > [ 57.749840] RIP: 0033:0x44fb79 > [ 57.749843] RSP: 002b:00007fbba84d9cf8 EFLAGS: 00000246 ORIG_RAX: > 00000000000000ca > [ 57.749850] RAX: fffffffffffffe00 RBX: 0000000000708218 RCX: 000000000044fb79 > [ 57.749854] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000708218 > [ 57.749857] RBP: 00000000007081f8 R08: 0000000000000000 R09: 0000000000000000 > [ 57.749860] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 > [ 57.749864] R13: 0000000000a5fc57 R14: 00007fbba84da9c0 R15: 000000000000000c > [ 57.749964] > [ 57.749966] =============================== > [ 57.749967] [ INFO: suspicious RCU usage. ] > [ 57.749971] 4.10.0+ #15 Not tainted > [ 57.749972] ------------------------------- > [ 57.749975] net/ipv4/ipmr.c:1238 suspicious > rcu_dereference_protected() usage! > [ 57.749977] > [ 57.749977] other info that might help us debug this: > [ 57.749977] > [ 57.749980] > [ 57.749980] rcu_scheduler_active = 2, debug_locks = 0 > [ 57.749982] no locks held by syz-executor2/5301. > [ 57.749984] > [ 57.749984] stack backtrace: > [ 57.749989] CPU: 1 PID: 5301 Comm: syz-executor2 Not tainted 4.10.0+ #15 > [ 57.749993] Hardware name: Google Google Compute Engine/Google > Compute Engine, BIOS Google 01/01/2011 > [ 57.749995] Call Trace: > [ 57.750001] dump_stack+0x2ee/0x3ef > [ 57.750117] lockdep_rcu_suspicious+0x139/0x180 > [ 57.750122] mrtsock_destruct+0x167/0x2f0 > [ 57.750144] ip_ra_control+0x459/0x600 > [ 57.750182] raw_close+0x19/0x30 > [ 57.750188] inet_release+0xed/0x1c0 > [ 57.750194] sock_release+0x8d/0x1e0 > [ 57.750208] sock_close+0x16/0x20 > [ 57.750213] __fput+0x332/0x7f0 > [ 57.750228] ____fput+0x15/0x20 > [ 57.750233] task_work_run+0x18a/0x260 > [ 57.750256] do_exit+0x18ef/0x28b0 > [ 57.750499] do_group_exit+0x149/0x420 > [ 57.750515] get_signal+0x7e0/0x1820 > [ 57.750556] do_signal+0xd2/0x2190 > [ 57.750604] exit_to_usermode_loop+0x200/0x2a0 > [ 57.750616] syscall_return_slowpath+0x4d3/0x570 > [ 57.750693] entry_SYSCALL_64_fastpath+0xc0/0xc2 > [ 57.750698] RIP: 0033:0x44fb79 > [ 57.750701] RSP: 002b:00007fbba84d9cf8 EFLAGS: 00000246 ORIG_RAX: > 00000000000000ca > [ 57.750708] RAX: fffffffffffffe00 RBX: 0000000000708218 RCX: 000000000044fb79 > [ 57.750712] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000708218 > [ 57.750716] RBP: 00000000007081f8 R08: 0000000000000000 R09: 0000000000000000 > [ 57.750720] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 > [ 57.750724] R13: 0000000000a5fc57 R14: 00007fbba84da9c0 R15: 000000000000000c Humm... but only on mmotm (git://git.kernel.org/pub/scm/linux/kernel/git/mhocko/mm.git auto-latest branch) linux-next and upstream seem to be fine
diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c index ebd953b..bda318a 100644 --- a/net/ipv4/ip_sockglue.c +++ b/net/ipv4/ip_sockglue.c @@ -591,6 +591,7 @@ static bool setsockopt_needs_rtnl(int optname) case MCAST_LEAVE_GROUP: case MCAST_LEAVE_SOURCE_GROUP: case MCAST_UNBLOCK_SOURCE: + case IP_ROUTER_ALERT: return true; } return false; diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c index beacd02..932321b 100644 --- a/net/ipv4/ipmr.c +++ b/net/ipv4/ipmr.c @@ -1278,7 +1278,7 @@ static void mrtsock_destruct(struct sock *sk) struct net *net = sock_net(sk); struct mr_table *mrt; - rtnl_lock(); + ASSERT_RTNL(); ipmr_for_each_table(mrt, net) { if (sk == rtnl_dereference(mrt->mroute_sk)) { IPV4_DEVCONF_ALL(net, MC_FORWARDING)--; @@ -1289,7 +1289,6 @@ static void mrtsock_destruct(struct sock *sk) mroute_clean_tables(mrt, false); } } - rtnl_unlock(); } /* Socket options and virtual interface manipulation. The whole @@ -1353,13 +1352,8 @@ int ip_mroute_setsockopt(struct sock *sk, int optname, char __user *optval, if (sk != rcu_access_pointer(mrt->mroute_sk)) { ret = -EACCES; } else { - /* We need to unlock here because mrtsock_destruct takes - * care of rtnl itself and we can't change that due to - * the IP_ROUTER_ALERT setsockopt which runs without it. - */ - rtnl_unlock(); ret = ip_ra_control(sk, 0, NULL); - goto out; + goto out_unlock; } break; case MRT_ADD_VIF: @@ -1470,7 +1464,6 @@ int ip_mroute_setsockopt(struct sock *sk, int optname, char __user *optval, } out_unlock: rtnl_unlock(); -out: return ret; }