Message ID | 20220426132011.25418-1-wanghai38@huawei.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | [net] SUNRPC: Fix local socket leak in xs_local_setup_socket() | expand |
On Tue, 2022-04-26 at 21:20 +0800, Wang Hai wrote: > If the connection to a local endpoint in xs_local_setup_socket() > fails, > fput() is missing in the error path, which will result in a socket > leak. > It can be reproduced in simple script below. > > while true > do > systemctl stop rpcbind.service > systemctl stop rpc-statd.service > systemctl stop nfs-server.service > > systemctl restart rpcbind.service > systemctl restart rpc-statd.service > systemctl restart nfs-server.service > done > > When executing the script, you can observe that the > "cat /proc/net/unix | wc -l" count keeps growing. > > Add the missing fput(), and restore transport to old socket. > > Signed-off-by: Wang Hai <wanghai38@huawei.com> > --- > net/sunrpc/xprtsock.c | 20 ++++++++++++++++++-- > 1 file changed, 18 insertions(+), 2 deletions(-) > > diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c > index 0f39e08ee580..7219c545385e 100644 > --- a/net/sunrpc/xprtsock.c > +++ b/net/sunrpc/xprtsock.c > @@ -1819,6 +1819,9 @@ static int xs_local_finish_connecting(struct > rpc_xprt *xprt, > { > struct sock_xprt *transport = container_of(xprt, struct > sock_xprt, > > xprt); > + struct socket *trans_sock = NULL; > + struct sock *trans_inet = NULL; > + int ret; > > if (!transport->inet) { > struct sock *sk = sock->sk; > @@ -1835,6 +1838,9 @@ static int xs_local_finish_connecting(struct > rpc_xprt *xprt, > > xprt_clear_connected(xprt); > > + trans_sock = transport->sock; > + trans_inet = transport->inet; > + Both values are NULL here > /* Reset to new socket */ > transport->sock = sock; > transport->inet = sk; > @@ -1844,7 +1850,14 @@ static int xs_local_finish_connecting(struct > rpc_xprt *xprt, > > xs_stream_start_connect(transport); > > - return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0); > + ret = kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0); > + /* Restore to old socket */ > + if (ret && trans_inet) { > + transport->sock = trans_sock; > + transport->inet = trans_inet; > + } > + > + return ret; > } > > /** > @@ -1887,7 +1900,7 @@ static int xs_local_setup_socket(struct > sock_xprt *transport) > xprt->stat.connect_time += (long)jiffies - > xprt->stat.connect_start; > xprt_set_connected(xprt); > - break; > + goto out; > case -ENOBUFS: > break; > case -ENOENT: > @@ -1904,6 +1917,9 @@ static int xs_local_setup_socket(struct > sock_xprt *transport) > xprt- > >address_strings[RPC_DISPLAY_ADDR]); > } > > + transport->file = NULL; > + fput(filp); Please just call xprt_force_disconnect() so that this can be cleaned up from a safe context. > + > out: > xprt_clear_connecting(xprt); > xprt_wake_pending_tasks(xprt, status);
在 2022/4/27 2:51, Trond Myklebust 写道: > On Tue, 2022-04-26 at 21:20 +0800, Wang Hai wrote: >> If the connection to a local endpoint in xs_local_setup_socket() >> fails, >> fput() is missing in the error path, which will result in a socket >> leak. >> It can be reproduced in simple script below. >> >> while true >> do >> systemctl stop rpcbind.service >> systemctl stop rpc-statd.service >> systemctl stop nfs-server.service >> >> systemctl restart rpcbind.service >> systemctl restart rpc-statd.service >> systemctl restart nfs-server.service >> done >> >> When executing the script, you can observe that the >> "cat /proc/net/unix | wc -l" count keeps growing. >> >> Add the missing fput(), and restore transport to old socket. >> >> Signed-off-by: Wang Hai <wanghai38@huawei.com> >> --- >> net/sunrpc/xprtsock.c | 20 ++++++++++++++++++-- >> 1 file changed, 18 insertions(+), 2 deletions(-) >> >> diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c >> index 0f39e08ee580..7219c545385e 100644 >> --- a/net/sunrpc/xprtsock.c >> +++ b/net/sunrpc/xprtsock.c >> @@ -1819,6 +1819,9 @@ static int xs_local_finish_connecting(struct >> rpc_xprt *xprt, >> { >> struct sock_xprt *transport = container_of(xprt, struct >> sock_xprt, >> >> xprt); >> + struct socket *trans_sock = NULL; >> + struct sock *trans_inet = NULL; >> + int ret; >> >> if (!transport->inet) { >> struct sock *sk = sock->sk; >> @@ -1835,6 +1838,9 @@ static int xs_local_finish_connecting(struct >> rpc_xprt *xprt, >> >> xprt_clear_connected(xprt); >> >> + trans_sock = transport->sock; >> + trans_inet = transport->inet; >> + > Both values are NULL here Got it, thanks > >> /* Reset to new socket */ >> transport->sock = sock; >> transport->inet = sk; >> @@ -1844,7 +1850,14 @@ static int xs_local_finish_connecting(struct >> rpc_xprt *xprt, >> >> xs_stream_start_connect(transport); >> >> - return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0); >> + ret = kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0); >> + /* Restore to old socket */ >> + if (ret && trans_inet) { >> + transport->sock = trans_sock; >> + transport->inet = trans_inet; >> + } >> + >> + return ret; >> } >> >> /** >> @@ -1887,7 +1900,7 @@ static int xs_local_setup_socket(struct >> sock_xprt *transport) >> xprt->stat.connect_time += (long)jiffies - >> xprt->stat.connect_start; >> xprt_set_connected(xprt); >> - break; >> + goto out; >> case -ENOBUFS: >> break; >> case -ENOENT: >> @@ -1904,6 +1917,9 @@ static int xs_local_setup_socket(struct >> sock_xprt *transport) >> xprt- >>> address_strings[RPC_DISPLAY_ADDR]); >> } >> >> + transport->file = NULL; >> + fput(filp); > Please just call xprt_force_disconnect() so that this can be cleaned up > from a safe context. Hi, Trond Thank you for your advice, I tried this, but it doesn't seem to work and an error is reported. I'll analyze why this happens diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c index 0f39e08ee580..3d1387b2cfbf 100644 --- a/net/sunrpc/xprtsock.c +++ b/net/sunrpc/xprtsock.c @@ -1887,7 +1887,7 @@ static int xs_local_setup_socket(struct sock_xprt *transport) xprt->stat.connect_time += (long)jiffies - xprt->stat.connect_start; xprt_set_connected(xprt); - break; + goto out; case -ENOBUFS: break; case -ENOENT: @@ -1904,6 +1904,8 @@ static int xs_local_setup_socket(struct sock_xprt *transport) xprt->address_strings[RPC_DISPLAY_ADDR]); } + xprt_force_disconnect(xprt); + out: xprt_clear_connecting(xprt); xprt_wake_pending_tasks(xprt, status); [ 2541.763895][ T8289] ------------[ cut here ]------------ [ 2541.765829][ T8289] WARNING: CPU: 0 PID: 8289 at kernel/workqueue.c:1499 __queue_work+0x72a/0x810 [ 2541.768862][ T8289] Modules linked in: [ 2541.770085][ T8289] CPU: 0 PID: 8289 Comm: gssproxy Tainted: G W 5.17.0+ #762 [ 2541.772724][ T8289] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014 [ 2541.773788][ T8289] RIP: 0010:__queue_work+0x72a/0x810 [ 2541.773788][ T8289] Code: 48 c7 c7 f8 7b b8 84 c6 05 b1 f4 39 04 01 e8 ad 65 05 00 e9 7f fe ff ff e8 33 94 11 00 4c 8b 33 e9 ff f9 ff ff e8 26 94 11 00 <0f> 0b e9 d2 fa ff ff e8 1a 94 11 00 4c 8d 7b 68 41 83 cc 02 e9 aa [ 2541.773788][ T8289] RSP: 0018:ffffc900083dfb20 EFLAGS: 00010093 [ 2541.773788][ T8289] RAX: 0000000000000000 RBX: ffff8881002a7900 RCX: 0000000000000000 [ 2541.773788][ T8289] RDX: ffff88824e091b40 RSI: ffffffff8119be6a RDI: ffffc900083dfb07 [ 2541.773788][ T8289] RBP: ffffc900083dfb60 R08: 0000000000000001 R09: 0000000000000000 [ 2541.773788][ T8289] R10: 0000000000000000 R11: 6e75732f74656e5b R12: 0000000000000000 [ 2541.773788][ T8289] R13: ffff88811a284668 R14: ffff888237c2d440 R15: ffff888243141c00 [ 2541.773788][ T8289] FS: 00007f3bb3f9dc40(0000) GS:ffff888237c00000(0000) knlGS:0000000000000000 [ 2541.773788][ T8289] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 2541.773788][ T8289] CR2: 00007f3bb04a72e0 CR3: 00000002602c5000 CR4: 00000000000006f0 [ 2541.773788][ T8289] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 2541.773788][ T8289] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 2541.773788][ T8289] Call Trace: [ 2541.773788][ T8289] <TASK> [ 2541.773788][ T8289] queue_work_on+0x88/0x90 [ 2541.773788][ T8289] xprt_schedule_autoclose_locked+0x7a/0xb0 [ 2541.773788][ T8289] xprt_force_disconnect+0x53/0x150 [ 2541.773788][ T8289] xs_local_setup_socket+0x131/0x3e0 [ 2541.823215][ T8289] xs_setup_local+0x24b/0x280 [ 2541.823215][ T8289] xprt_create_transport+0xb0/0x340 [ 2541.823215][ T8289] rpc_create+0x104/0x2b0 [ 2541.823215][ T8289] gssp_rpc_create+0x93/0xe0 [ 2541.823215][ T8289] set_gssp_clnt+0xd9/0x230 [ 2541.823215][ T8289] write_gssp+0xb9/0x130 [ 2541.823215][ T8289] ? lock_acquire+0x1de/0x2f0 [ 2541.823215][ T8289] proc_reg_write+0xd2/0x110 [ 2541.823215][ T8289] ? set_gss_proxy+0x1d0/0x1d0 [ 2541.823215][ T8289] ? proc_reg_compat_ioctl+0x100/0x100 [ 2541.823215][ T8289] vfs_write+0x11d/0x4b0 [ 2541.841496][ T8289] ksys_write+0xe0/0x130 [ 2541.841496][ T8289] __x64_sys_write+0x23/0x30 [ 2541.841496][ T8289] do_syscall_64+0x34/0xb0 [ 2541.841496][ T8289] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 2541.841496][ T8289] RIP: 0033:0x7f3bb0811280 [ 2541.841496][ T8289] Code: 00 c3 0f 1f 84 00 00 00 00 00 48 8b 05 c1 8c 20 00 c3 0f 1f 84 00 00 00 00 00 83 3d 09 cf 20 00 00 75 10 b8 01 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 6e fd ff ff 48 89 04 24 [ 2541.841496][ T8289] RSP: 002b:00007ffc59024c98 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 [ 2541.841496][ T8289] RAX: ffffffffffffffda RBX: 0000000000000009 RCX: 00007f3bb0811280 [ 2541.841496][ T8289] RDX: 0000000000000001 RSI: 00007ffc59024ca6 RDI: 0000000000000009 [ 2541.841496][ T8289] RBP: 0000000000000000 R08: 0000000000000020 R09: 0000000000000060 [ 2541.841496][ T8289] R10: 0000561545627900 R11: 0000000000000246 R12: 0000561545630580 [ 2541.841496][ T8289] R13: 00007ffc59024fd0 R14: 0000000000000000 R15: 0000000000000000 [ 2541.841496][ T8289] </TASK> [ 2541.841496][ T8289] irq event stamp: 0 [ 2541.841496][ T8289] hardirqs last enabled at (0): [<0000000000000000>] 0x0 [ 2541.841496][ T8289] hardirqs last disabled at (0): [<ffffffff81165e25>] copy_process+0xb35/0x2410 [ 2541.841496][ T8289] softirqs last enabled at (0): [<ffffffff81165e25>] copy_process+0xb35/0x2410 [ 2541.841496][ T8289] softirqs last disabled at (0): [<0000000000000000>] 0x0 [ 2541.841496][ T8289] ---[ end trace 0000000000000000 ]--- >> + >> out: >> xprt_clear_connecting(xprt); >> xprt_wake_pending_tasks(xprt, status);
在 2022/4/27 15:15, wanghai (M) 写道: > > 在 2022/4/27 2:51, Trond Myklebust 写道: >> On Tue, 2022-04-26 at 21:20 +0800, Wang Hai wrote: >>> If the connection to a local endpoint in xs_local_setup_socket() >>> fails, >>> fput() is missing in the error path, which will result in a socket >>> leak. >>> It can be reproduced in simple script below. >>> >>> while true >>> do >>> systemctl stop rpcbind.service >>> systemctl stop rpc-statd.service >>> systemctl stop nfs-server.service >>> >>> systemctl restart rpcbind.service >>> systemctl restart rpc-statd.service >>> systemctl restart nfs-server.service >>> done >>> >>> When executing the script, you can observe that the >>> "cat /proc/net/unix | wc -l" count keeps growing. >>> >>> Add the missing fput(), and restore transport to old socket. >>> >>> Signed-off-by: Wang Hai <wanghai38@huawei.com> >>> --- >>> net/sunrpc/xprtsock.c | 20 ++++++++++++++++++-- >>> 1 file changed, 18 insertions(+), 2 deletions(-) >>> >>> diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c >>> index 0f39e08ee580..7219c545385e 100644 >>> --- a/net/sunrpc/xprtsock.c >>> +++ b/net/sunrpc/xprtsock.c >>> @@ -1819,6 +1819,9 @@ static int xs_local_finish_connecting(struct >>> rpc_xprt *xprt, >>> { >>> struct sock_xprt *transport = container_of(xprt, struct >>> sock_xprt, >>> xprt); >>> + struct socket *trans_sock = NULL; >>> + struct sock *trans_inet = NULL; >>> + int ret; >>> if (!transport->inet) { >>> struct sock *sk = sock->sk; >>> @@ -1835,6 +1838,9 @@ static int xs_local_finish_connecting(struct >>> rpc_xprt *xprt, >>> xprt_clear_connected(xprt); >>> + trans_sock = transport->sock; >>> + trans_inet = transport->inet; >>> + >> Both values are NULL here > Got it, thanks >> >>> /* Reset to new socket */ >>> transport->sock = sock; >>> transport->inet = sk; >>> @@ -1844,7 +1850,14 @@ static int xs_local_finish_connecting(struct >>> rpc_xprt *xprt, >>> xs_stream_start_connect(transport); >>> - return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0); >>> + ret = kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0); >>> + /* Restore to old socket */ >>> + if (ret && trans_inet) { >>> + transport->sock = trans_sock; >>> + transport->inet = trans_inet; >>> + } >>> + >>> + return ret; >>> } >>> /** >>> @@ -1887,7 +1900,7 @@ static int xs_local_setup_socket(struct >>> sock_xprt *transport) >>> xprt->stat.connect_time += (long)jiffies - >>> xprt->stat.connect_start; >>> xprt_set_connected(xprt); >>> - break; >>> + goto out; >>> case -ENOBUFS: >>> break; >>> case -ENOENT: >>> @@ -1904,6 +1917,9 @@ static int xs_local_setup_socket(struct >>> sock_xprt *transport) >>> xprt- >>>> address_strings[RPC_DISPLAY_ADDR]); >>> } >>> + transport->file = NULL; >>> + fput(filp); >> Please just call xprt_force_disconnect() so that this can be cleaned up >> from a safe context. > > Hi, Trond > > Thank you for your advice, I tried this, but it doesn't seem to > > work and an error is reported. I'll analyze why this happens > > Hi, Trond. If I call xprt_force_disconnect(), it reports the following error, I spent a long time but couldn't find the cause of the error. If I call xs_close(), it works, is it possible to call xs_close() here? [ 107.147326][ T7128] ====================================================== [ 107.147329][ T7128] WARNING: possible circular locking dependency detected [ 107.147333][ T7128] 5.17.0+ #10 Not tainted [ 107.147340][ T7128] ------------------------------------------------------ [ 107.147343][ T7128] rpc.nfsd/7128 is trying to acquire lock: [ 107.147349][ T7128] ffffffff850f4960 (console_owner){..-.}-{0:0}, at: console_unlock+0x1d7/0x790 [ 107.147384][ T7128] [ 107.147384][ T7128] but task is already holding lock: [ 107.147387][ T7128] ffff88824010b418 (&pool->lock/1){-.-.}-{2:2}, at: __queue_work+0x450/0x810 [ 107.147420][ T7128] [ 107.147420][ T7128] which lock already depends on the new lock. [ 107.147420][ T7128] [ 107.147423][ T7128] [ 107.147423][ T7128] the existing dependency chain (in reverse order) is: [ 107.147426][ T7128] [ 107.147426][ T7128] -> #2 (&pool->lock/1){-.-.}-{2:2}: [ 107.147444][ T7128] _raw_spin_lock+0x32/0x50 [ 107.147482][ T7128] __queue_work+0x131/0x810 [ 107.147496][ T7128] queue_work_on+0x88/0x90 [ 107.147509][ T7128] tty_flip_buffer_push+0x34/0x40 [ 107.147525][ T7128] serial8250_rx_chars+0x73/0x80 [ 107.147537][ T7128] serial8250_handle_irq.part.21+0x124/0x160 [ 107.147552][ T7128] serial8250_default_handle_irq+0x79/0x90 [ 107.147566][ T7128] serial8250_interrupt+0x73/0xd0 [ 107.147581][ T7128] __handle_irq_event_percpu+0x54/0x3c0 [ 107.147597][ T7128] handle_irq_event_percpu+0x1c/0x50 [ 107.147611][ T7128] handle_irq_event+0x3e/0x60 [ 107.147624][ T7128] handle_edge_irq+0xc3/0x250 [ 107.147636][ T7128] __common_interrupt+0x71/0x140 [ 107.147649][ T7128] common_interrupt+0xbc/0xe0 [ 107.147664][ T7128] asm_common_interrupt+0x1e/0x40 [ 107.147677][ T7128] default_idle+0x14/0x20 [ 107.147687][ T7128] arch_cpu_idle+0xf/0x20 [ 107.147698][ T7128] default_idle_call+0x6f/0x230 [ 107.147709][ T7128] do_idle+0x1c4/0x250 [ 107.147722][ T7128] cpu_startup_entry+0x1d/0x20 [ 107.147736][ T7128] start_secondary+0xe6/0xf0 [ 107.147751][ T7128] secondary_startup_64_no_verify+0xc3/0xcb [ 107.147767][ T7128] [ 107.147767][ T7128] -> #1 (&port_lock_key){-.-.}-{2:2}: [ 107.147783][ T7128] _raw_spin_lock_irqsave+0x42/0x60 [ 107.147795][ T7128] serial8250_console_write+0x31b/0x380 [ 107.147808][ T7128] univ8250_console_write+0x3a/0x50 [ 107.147820][ T7128] console_unlock+0x51d/0x790 [ 107.147832][ T7128] vprintk_emit+0x252/0x320 [ 107.147844][ T7128] vprintk_default+0x2b/0x30 [ 107.147856][ T7128] vprintk+0x71/0x80 [ 107.147868][ T7128] _printk+0x63/0x82 [ 107.147879][ T7128] register_console+0x233/0x400 [ 107.147892][ T7128] univ8250_console_init+0x35/0x3f [ 107.147907][ T7128] console_init+0x233/0x345 [ 107.147920][ T7128] start_kernel+0xa70/0xbf8 [ 107.147931][ T7128] x86_64_start_reservations+0x2a/0x2c [ 107.147947][ T7128] x86_64_start_kernel+0x90/0x95 [ 107.147961][ T7128] secondary_startup_64_no_verify+0xc3/0xcb [ 107.147975][ T7128] [ 107.147975][ T7128] -> #0 (console_owner){..-.}-{0:0}: [ 107.147990][ T7128] __lock_acquire+0x1552/0x1a30 [ 107.148002][ T7128] lock_acquire+0x25e/0x2f0 [ 107.148014][ T7128] console_unlock+0x22e/0x790 [ 107.148026][ T7128] vprintk_emit+0x252/0x320 [ 107.148038][ T7128] vprintk_default+0x2b/0x30 [ 107.148050][ T7128] vprintk+0x71/0x80 [ 107.148061][ T7128] _printk+0x63/0x82 [ 107.148072][ T7128] report_bug+0x1a6/0x1c0 [ 107.148085][ T7128] handle_bug+0x43/0x70 [ 107.148098][ T7128] exc_invalid_op+0x18/0x70 [ 107.148111][ T7128] asm_exc_invalid_op+0x12/0x20 [ 107.148123][ T7128] __queue_work+0x72a/0x810 [ 107.148136][ T7128] queue_work_on+0x88/0x90 [ 107.148149][ T7128] xprt_schedule_autoclose_locked+0x7a/0xb0 [ 107.148162][ T7128] xprt_force_disconnect+0x53/0x150 [ 107.148173][ T7128] xs_local_setup_socket+0x2b2/0x480 [ 107.148188][ T7128] xs_setup_local+0x24b/0x280 [ 107.148200][ T7128] xprt_create_transport+0xb0/0x340 [ 107.148212][ T7128] rpc_create+0x104/0x2b0 [ 107.148226][ T7128] rpcb_create_local_unix+0xb2/0x2c0 [ 107.148242][ T7128] rpcb_create_local+0x79/0x90 [ 107.148256][ T7128] svc_bind+0x92/0xd0 [ 107.148267][ T7128] nfsd_create_serv+0x131/0x3a0 [ 107.148280][ T7128] write_ports+0x2d4/0x8d0 [ 107.148292][ T7128] nfsctl_transaction_write+0x70/0xb0 [ 107.148305][ T7128] vfs_write+0x11d/0x4b0 [ 107.148319][ T7128] ksys_write+0xe0/0x130 [ 107.148330][ T7128] __x64_sys_write+0x23/0x30 [ 107.148343][ T7128] do_syscall_64+0x34/0xb0 [ 107.148356][ T7128] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 107.148369][ T7128] [ 107.148369][ T7128] other info that might help us debug this: [ 107.148369][ T7128] [ 107.148372][ T7128] Chain exists of: [ 107.148372][ T7128] console_owner --> &port_lock_key --> &pool->lock/1 [ 107.148372][ T7128] [ 107.148392][ T7128] Possible unsafe locking scenario: [ 107.148392][ T7128] [ 107.148395][ T7128] CPU0 CPU1 [ 107.148397][ T7128] ---- ---- [ 107.148399][ T7128] lock(&pool->lock/1); [ 107.148409][ T7128] lock(&port_lock_key); [ 107.148416][ T7128] lock(&pool->lock/1); [ 107.148426][ T7128] lock(console_owner); [ 107.148432][ T7128] [ 107.148432][ T7128] *** DEADLOCK *** [ 107.148432][ T7128] [ 107.148434][ T7128] 7 locks held by rpc.nfsd/7128: [ 107.148442][ T7128] #0: ffff8882480a4460 (sb_writers#12){.+.+}-{0:0}, at: ksys_write+0xe0/0x130 [ 107.148474][ T7128] #1: ffffffff8526ee88 (nfsd_mutex){+.+.}-{3:3}, at: write_ports+0x41/0x8d0 [ 107.148503][ T7128] #2: ffffffff854cdc88 (rpcb_create_local_mutex){+.+.}-{3:3}, at: rpcb_create_local+0x43/0x90 [ 107.148534][ T7128] #3: ffff888243f14740 (&xprt->transport_lock){+.+.}-{2:2}, at: xprt_force_disconnect+0x4b/0x150 [ 107.148562][ T7128] #4: ffffffff851d7a60 (rcu_read_lock){....}-{1:2}, at: __queue_work+0x5a/0x810 [ 107.148592][ T7128] #5: ffff88824010b418 (&pool->lock/1){-.-.}-{2:2}, at: __queue_work+0x450/0x810 [ 107.148625][ T7128] #6: ffffffff851d4d60 (console_lock){+.+.}-{0:0}, at: vprintk_emit+0x114/0x320 [ 107.148653][ T7128] [ 107.148653][ T7128] stack backtrace: [ 107.148656][ T7128] CPU: 3 PID: 7128 Comm: rpc.nfsd Not tainted 5.17.0+ #10 [ 107.148670][ T7128] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014 [ 107.148677][ T7128] Call Trace: [ 107.148680][ T7128] <TASK> [ 107.148685][ T7128] dump_stack_lvl+0x6c/0x8b [ 107.148702][ T7128] dump_stack+0x15/0x17 [ 107.148715][ T7128] print_circular_bug.isra.46+0x261/0x2c0 [ 107.148767][ T7128] check_noncircular+0x105/0x120 [ 107.148787][ T7128] __lock_acquire+0x1552/0x1a30 [ 107.148800][ T7128] ? __lock_acquire+0x1552/0x1a30 [ 107.148820][ T7128] lock_acquire+0x25e/0x2f0 [ 107.148833][ T7128] ? console_unlock+0x1d7/0x790 [ 107.148848][ T7128] ? lock_release+0x204/0x2c0 [ 107.148865][ T7128] console_unlock+0x22e/0x790 [ 107.148878][ T7128] ? console_unlock+0x1d7/0x790 [ 107.148900][ T7128] vprintk_emit+0x252/0x320 [ 107.148916][ T7128] vprintk_default+0x2b/0x30 [ 107.148931][ T7128] vprintk+0x71/0x80 [ 107.148945][ T7128] _printk+0x63/0x82 [ 107.148959][ T7128] ? report_bug+0x19a/0x1c0 [ 107.148974][ T7128] ? __queue_work+0x72a/0x810 [ 107.148988][ T7128] report_bug+0x1a6/0x1c0 [ 107.149004][ T7128] handle_bug+0x43/0x70 [ 107.149019][ T7128] exc_invalid_op+0x18/0x70 [ 107.149034][ T7128] asm_exc_invalid_op+0x12/0x20 [ 107.149047][ T7128] RIP: 0010:__queue_work+0x72a/0x810 [ 107.149063][ T7128] Code: 48 c7 c7 78 7b b8 84 c6 05 b1 f4 39 04 01 e8 ad 65 05 00 e9 7f fe ff ff e8 33 94 11 00 4c 8b 33 e9 ff f9 ff ff e8 26 94 11 00 <0f> 0b e9 d2 fa ff ff e8 1a 94 11 00 4c 8d 7b 68 41 83 cc 02 e9 aa [ 107.149077][ T7128] RSP: 0018:ffffc900042efa88 EFLAGS: 00010093 [ 107.149087][ T7128] RAX: 0000000000000000 RBX: ffff88824013c100 RCX: 0000000000000000 [ 107.149096][ T7128] RDX: ffff888111b15140 RSI: ffffffff8119be6a RDI: ffffffff84c6fd9e [ 107.149104][ T7128] RBP: ffffc900042efac8 R08: 0000000000000001 R09: 0000000000000000 [ 107.149112][ T7128] R10: 0000000000000002 R11: 000000000000f2ce R12: 0000000000000000 [ 107.149120][ T7128] R13: ffff888243f14668 R14: ffff888237c2d440 R15: ffff888240ffc000 [ 107.149134][ T7128] ? __queue_work+0x72a/0x810 [ 107.149151][ T7128] ? __queue_work+0x72a/0x810 [ 107.149169][ T7128] queue_work_on+0x88/0x90 [ 107.149185][ T7128] xprt_schedule_autoclose_locked+0x7a/0xb0 [ 107.149200][ T7128] xprt_force_disconnect+0x53/0x150 [ 107.149213][ T7128] xs_local_setup_socket+0x2b2/0x480 [ 107.149230][ T7128] xs_setup_local+0x24b/0x280 [ 107.149245][ T7128] xprt_create_transport+0xb0/0x340 [ 107.149259][ T7128] rpc_create+0x104/0x2b0 [ 107.149278][ T7128] ? __this_cpu_preempt_check+0x1c/0x20 [ 107.149293][ T7128] ? lock_is_held_type+0xde/0x130 [ 107.149307][ T7128] rpcb_create_local_unix+0xb2/0x2c0 [ 107.149332][ T7128] rpcb_create_local+0x79/0x90 [ 107.149348][ T7128] svc_bind+0x92/0xd0 [ 107.149363][ T7128] nfsd_create_serv+0x131/0x3a0 [ 107.149378][ T7128] write_ports+0x2d4/0x8d0 [ 107.149392][ T7128] ? _copy_from_user+0x8b/0xe0 [ 107.149411][ T7128] ? nfsd_init_net+0x2d0/0x2d0 [ 107.149425][ T7128] nfsctl_transaction_write+0x70/0xb0 [ 107.149439][ T7128] ? export_features_show+0x30/0x30 [ 107.149454][ T7128] vfs_write+0x11d/0x4b0 [ 107.149470][ T7128] ksys_write+0xe0/0x130 [ 107.149486][ T7128] __x64_sys_write+0x23/0x30 [ 107.149501][ T7128] do_syscall_64+0x34/0xb0 [ 107.149515][ T7128] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 107.149530][ T7128] RIP: 0033:0x7feb99b00130 [ 107.149540][ T7128] Code: 73 01 c3 48 8b 0d 58 ed 2c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d b9 45 2d 00 00 75 10 b8 01 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 3e f3 01 00 48 89 04 24 [ 107.149553][ T7128] RSP: 002b:00007ffc849b68e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 [ 107.149565][ T7128] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007feb99b00130 [ 107.149574][ T7128] RDX: 0000000000000002 RSI: 000055d532e09620 RDI: 0000000000000003 [ 107.149581][ T7128] RBP: 0000000000000003 R08: 000055d532c06704 R09: 0000000000000000 [ 107.149589][ T7128] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000004 [ 107.149597][ T7128] R13: 000055d532e09620 R14: 000055d532c066bf R15: 000055d533474730 [ 107.149614][ T7128] </TASK> [ 107.283659][ T7128] WARNING: CPU: 3 PID: 7128 at kernel/workqueue.c:1499 __queue_work+0x72a/0x810 [ 107.283659][ T7128] Modules linked in: [ 107.283659][ T7128] CPU: 3 PID: 7128 Comm: rpc.nfsd Not tainted 5.17.0+ #10 [ 107.283659][ T7128] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014 [ 107.283659][ T7128] RIP: 0010:__queue_work+0x72a/0x810 [ 107.283659][ T7128] Code: 48 c7 c7 78 7b b8 84 c6 05 b1 f4 39 04 01 e8 ad 65 05 00 e9 7f fe ff ff e8 33 94 11 00 4c 8b 33 e9 ff f9 ff ff e8 26 94 11 00 <0f> 0b e9 d2 fa ff ff e8 1a 94 11 00 4c 8d 7b 68 41 83 cc 02 e9 aa [ 107.283659][ T7128] RSP: 0018:ffffc900042efa88 EFLAGS: 00010093 [ 107.283659][ T7128] RAX: 0000000000000000 RBX: ffff88824013c100 RCX: 0000000000000000 [ 107.283659][ T7128] RDX: ffff888111b15140 RSI: ffffffff8119be6a RDI: ffffffff84c6fd9e [ 107.283659][ T7128] RBP: ffffc900042efac8 R08: 0000000000000001 R09: 0000000000000000 [ 107.283659][ T7128] R10: 0000000000000002 R11: 000000000000f2ce R12: 0000000000000000 [ 107.283659][ T7128] R13: ffff888243f14668 R14: ffff888237c2d440 R15: ffff888240ffc000 [ 107.283659][ T7128] FS: 00007feb9a89ac80(0000) GS:ffff888437c80000(0000) knlGS:0000000000000000 [ 107.283659][ T7128] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 107.283659][ T7128] CR2: 00007ffc849ba084 CR3: 0000000247402000 CR4: 00000000000006e0 [ 107.283659][ T7128] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 107.283659][ T7128] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 107.283659][ T7128] Call Trace: [ 107.283659][ T7128] <TASK> [ 107.283659][ T7128] queue_work_on+0x88/0x90 [ 107.283659][ T7128] xprt_schedule_autoclose_locked+0x7a/0xb0 [ 107.283659][ T7128] xprt_force_disconnect+0x53/0x150 [ 107.283659][ T7128] xs_local_setup_socket+0x2b2/0x480 [ 107.283659][ T7128] xs_setup_local+0x24b/0x280 [ 107.283659][ T7128] xprt_create_transport+0xb0/0x340 [ 107.283659][ T7128] rpc_create+0x104/0x2b0 [ 107.283659][ T7128] ? __this_cpu_preempt_check+0x1c/0x20 [ 107.283659][ T7128] ? lock_is_held_type+0xde/0x130 [ 107.283659][ T7128] rpcb_create_local_unix+0xb2/0x2c0 [ 107.283659][ T7128] rpcb_create_local+0x79/0x90 [ 107.283659][ T7128] svc_bind+0x92/0xd0 [ 107.283659][ T7128] nfsd_create_serv+0x131/0x3a0 [ 107.283659][ T7128] write_ports+0x2d4/0x8d0 [ 107.283659][ T7128] ? _copy_from_user+0x8b/0xe0 [ 107.283659][ T7128] ? nfsd_init_net+0x2d0/0x2d0 [ 107.283659][ T7128] nfsctl_transaction_write+0x70/0xb0 [ 107.283659][ T7128] ? export_features_show+0x30/0x30 [ 107.283659][ T7128] vfs_write+0x11d/0x4b0 [ 107.283659][ T7128] ksys_write+0xe0/0x130 [ 107.283659][ T7128] __x64_sys_write+0x23/0x30 [ 107.283659][ T7128] do_syscall_64+0x34/0xb0 [ 107.283659][ T7128] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 107.283659][ T7128] RIP: 0033:0x7feb99b00130 [ 107.283659][ T7128] Code: 73 01 c3 48 8b 0d 58 ed 2c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d b9 45 2d 00 00 75 10 b8 01 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 3e f3 01 00 48 89 04 24 [ 107.283659][ T7128] RSP: 002b:00007ffc849b68e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 [ 107.283659][ T7128] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007feb99b00130 [ 107.283659][ T7128] RDX: 0000000000000002 RSI: 000055d532e09620 RDI: 0000000000000003 [ 107.283659][ T7128] RBP: 0000000000000003 R08: 000055d532c06704 R09: 0000000000000000 [ 107.283659][ T7128] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000004 [ 107.283659][ T7128] R13: 000055d532e09620 R14: 000055d532c066bf R15: 000055d533474730 [ 107.283659][ T7128] </TASK> [ 107.283659][ T7128] irq event stamp: 33702 [ 107.283659][ T7128] hardirqs last enabled at (33701): [<ffffffff814c2288>] cmpxchg_double_slab.isra.52+0xe8/0x220 [ 107.283659][ T7128] hardirqs last disabled at (33702): [<ffffffff8119bfc3>] queue_work_on+0x73/0x90 [ 107.283659][ T7128] softirqs last enabled at (33670): [<ffffffff8367b7cc>] unix_release_sock+0xfc/0x540 [ 107.283659][ T7128] softirqs last disabled at (33668): [<ffffffff8367b7a8>] unix_release_sock+0xd8/0x540 [ 107.283659][ T7128] ---[ end trace 0000000000000000 ]--- [ 107.622086][ T7128] svc: failed to register nfsdv2 RPC service (errno 111). [ 107.627373][ T7128] svc: failed to register nfsaclv2 RPC service (errno 111). Job for nfs-server.service canceled. [ 109.560632][ T7174] NFSD: Using UMH upcall client tracking operations. [ 109.564229][ T7174] NFSD: starting 90-second grace period (net f0000000) >>> + >>> out: >>> xprt_clear_connecting(xprt); >>> xprt_wake_pending_tasks(xprt, status); >
diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c index 0f39e08ee580..7219c545385e 100644 --- a/net/sunrpc/xprtsock.c +++ b/net/sunrpc/xprtsock.c @@ -1819,6 +1819,9 @@ static int xs_local_finish_connecting(struct rpc_xprt *xprt, { struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); + struct socket *trans_sock = NULL; + struct sock *trans_inet = NULL; + int ret; if (!transport->inet) { struct sock *sk = sock->sk; @@ -1835,6 +1838,9 @@ static int xs_local_finish_connecting(struct rpc_xprt *xprt, xprt_clear_connected(xprt); + trans_sock = transport->sock; + trans_inet = transport->inet; + /* Reset to new socket */ transport->sock = sock; transport->inet = sk; @@ -1844,7 +1850,14 @@ static int xs_local_finish_connecting(struct rpc_xprt *xprt, xs_stream_start_connect(transport); - return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0); + ret = kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0); + /* Restore to old socket */ + if (ret && trans_inet) { + transport->sock = trans_sock; + transport->inet = trans_inet; + } + + return ret; } /** @@ -1887,7 +1900,7 @@ static int xs_local_setup_socket(struct sock_xprt *transport) xprt->stat.connect_time += (long)jiffies - xprt->stat.connect_start; xprt_set_connected(xprt); - break; + goto out; case -ENOBUFS: break; case -ENOENT: @@ -1904,6 +1917,9 @@ static int xs_local_setup_socket(struct sock_xprt *transport) xprt->address_strings[RPC_DISPLAY_ADDR]); } + transport->file = NULL; + fput(filp); + out: xprt_clear_connecting(xprt); xprt_wake_pending_tasks(xprt, status);
If the connection to a local endpoint in xs_local_setup_socket() fails, fput() is missing in the error path, which will result in a socket leak. It can be reproduced in simple script below. while true do systemctl stop rpcbind.service systemctl stop rpc-statd.service systemctl stop nfs-server.service systemctl restart rpcbind.service systemctl restart rpc-statd.service systemctl restart nfs-server.service done When executing the script, you can observe that the "cat /proc/net/unix | wc -l" count keeps growing. Add the missing fput(), and restore transport to old socket. Signed-off-by: Wang Hai <wanghai38@huawei.com> --- net/sunrpc/xprtsock.c | 20 ++++++++++++++++++-- 1 file changed, 18 insertions(+), 2 deletions(-)