syzbot


possible deadlock in rds_wake_sk_sleep (4)

Status: upstream: reported C repro on 2022/05/19 03:35
Reported-by: syzbot+dcd73ff9291e6d34b3ab@syzkaller.appspotmail.com
First crash: 40d, last: 10d

Cause bisection: the issue happens on the oldest tested release (bisect log)
Crash: possible deadlock in rds_wake_sk_sleep (log)
Repro: C syz .config
similar bugs (4):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream possible deadlock in rds_wake_sk_sleep (2) 1 874d 872d 0/22 auto-closed as invalid on 2020/05/31 18:56
linux-4.19 possible deadlock in rds_wake_sk_sleep C error 1 192d 192d 0/1 upstream: reported C repro on 2021/12/15 07:20
upstream possible deadlock in rds_wake_sk_sleep (3) 3 661d 732d 0/22 auto-closed as invalid on 2020/12/31 09:16
upstream possible deadlock in rds_wake_sk_sleep 8 1318d 1417d 0/22 auto-closed as invalid on 2019/05/14 04:22
Patch testing requests:
Created Duration User Patch Repo Result
2022/05/19 11:52 18m hdanton@sina.com patch https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/ 1e1b28b936ae OK

Sample crash report:
======================================================
WARNING: possible circular locking dependency detected
5.18.0-rc7-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor423/5373 is trying to acquire lock:
ffff8880502af2a8 (&rs->rs_recv_lock){...-}-{2:2}, at: rds_wake_sk_sleep+0x2a/0xd0 net/rds/af_rds.c:109

but task is already holding lock:
ffff88807c7cc900 (&rm->m_rs_lock){..-.}-{2:2}, at: rds_send_remove_from_sock+0x14b/0x8c0 net/rds/send.c:628

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&rm->m_rs_lock){..-.}-{2:2}:
       lock_acquire+0x1a7/0x400 kernel/locking/lockdep.c:5641
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162
       rds_message_purge net/rds/message.c:138 [inline]
       rds_message_put+0x13c/0xab0 net/rds/message.c:180
       rds_inc_put net/rds/recv.c:82 [inline]
       rds_clear_recv_queue+0x2bb/0x390 net/rds/recv.c:767
       rds_release+0xbe/0x2d0 net/rds/af_rds.c:73
       __sock_release net/socket.c:650 [inline]
       sock_close+0xd7/0x260 net/socket.c:1318
       __fput+0x3b9/0x820 fs/file_table.c:317
       task_work_run+0x146/0x1c0 kernel/task_work.c:164
       ptrace_notify+0x29f/0x350 kernel/signal.c:2361
       ptrace_report_syscall include/linux/ptrace.h:427 [inline]
       ptrace_report_syscall_exit include/linux/ptrace.h:489 [inline]
       syscall_exit_work+0x8c/0xe0 kernel/entry/common.c:249
       syscall_exit_to_user_mode_prepare+0x62/0x80 kernel/entry/common.c:276
       __syscall_exit_to_user_mode_work kernel/entry/common.c:281 [inline]
       syscall_exit_to_user_mode+0xa/0x70 kernel/entry/common.c:294
       entry_SYSCALL_64_after_hwframe+0x44/0xae

-> #0 (&rs->rs_recv_lock){...-}-{2:2}:
       check_prev_add kernel/locking/lockdep.c:3065 [inline]
       check_prevs_add kernel/locking/lockdep.c:3188 [inline]
       validate_chain+0x185c/0x65c0 kernel/locking/lockdep.c:3803
       __lock_acquire+0x129a/0x1f80 kernel/locking/lockdep.c:5029
       lock_acquire+0x1a7/0x400 kernel/locking/lockdep.c:5641
       __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline]
       _raw_read_lock_irqsave+0xd9/0x120 kernel/locking/spinlock.c:236
       rds_wake_sk_sleep+0x2a/0xd0 net/rds/af_rds.c:109
       rds_send_remove_from_sock+0x1fd/0x8c0 net/rds/send.c:634
       rds_send_path_drop_acked+0x380/0x3c0 net/rds/send.c:710
       rds_tcp_write_space+0x192/0x520 net/rds/tcp_send.c:198
       tcp_new_space net/ipv4/tcp_input.c:5455 [inline]
       tcp_check_space+0x35d/0x4f0 net/ipv4/tcp_input.c:5474
       tcp_data_snd_check net/ipv4/tcp_input.c:5483 [inline]
       tcp_rcv_established+0xa60/0x1a50 net/ipv4/tcp_input.c:5981
       tcp_v4_do_rcv+0x479/0xa60 net/ipv4/tcp_ipv4.c:1660
       sk_backlog_rcv include/net/sock.h:1051 [inline]
       __release_sock+0x1d8/0x4c0 net/core/sock.c:2794
       release_sock+0x5d/0x1c0 net/core/sock.c:3327
       rds_send_xmit+0x1e5d/0x2690 net/rds/send.c:422
       rds_sendmsg+0x1bdf/0x2290 net/rds/send.c:1382
       sock_sendmsg_nosec net/socket.c:705 [inline]
       sock_sendmsg net/socket.c:725 [inline]
       __sys_sendto+0x42e/0x5b0 net/socket.c:2040
       __do_sys_sendto net/socket.c:2052 [inline]
       __se_sys_sendto net/socket.c:2048 [inline]
       __x64_sys_sendto+0xda/0xf0 net/socket.c:2048
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x44/0xae

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&rm->m_rs_lock);
                               lock(&rs->rs_recv_lock);
                               lock(&rm->m_rs_lock);
  lock(&rs->rs_recv_lock);

 *** DEADLOCK ***

3 locks held by syz-executor423/5373:
 #0: ffff888074c4ed30 (k-sk_lock-AF_INET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1682 [inline]
 #0: ffff888074c4ed30 (k-sk_lock-AF_INET){+.+.}-{0:0}, at: tcp_sock_set_cork+0x29/0x1b0 net/ipv4/tcp.c:3236
 #1: ffff888074c4efc0 (k-clock-AF_INET){++.-}-{2:2}, at: rds_tcp_write_space+0x30/0x520 net/rds/tcp_send.c:184
 #2: ffff88807c7cc900 (&rm->m_rs_lock){..-.}-{2:2}, at: rds_send_remove_from_sock+0x14b/0x8c0 net/rds/send.c:628

stack backtrace:
CPU: 1 PID: 5373 Comm: syz-executor423 Not tainted 5.18.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 check_noncircular+0x2f7/0x3b0 kernel/locking/lockdep.c:2145
 check_prev_add kernel/locking/lockdep.c:3065 [inline]
 check_prevs_add kernel/locking/lockdep.c:3188 [inline]
 validate_chain+0x185c/0x65c0 kernel/locking/lockdep.c:3803
 __lock_acquire+0x129a/0x1f80 kernel/locking/lockdep.c:5029
 lock_acquire+0x1a7/0x400 kernel/locking/lockdep.c:5641
 __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline]
 _raw_read_lock_irqsave+0xd9/0x120 kernel/locking/spinlock.c:236
 rds_wake_sk_sleep+0x2a/0xd0 net/rds/af_rds.c:109
 rds_send_remove_from_sock+0x1fd/0x8c0 net/rds/send.c:634
 rds_send_path_drop_acked+0x380/0x3c0 net/rds/send.c:710
 rds_tcp_write_space+0x192/0x520 net/rds/tcp_send.c:198
 tcp_new_space net/ipv4/tcp_input.c:5455 [inline]
 tcp_check_space+0x35d/0x4f0 net/ipv4/tcp_input.c:5474
 tcp_data_snd_check net/ipv4/tcp_input.c:5483 [inline]
 tcp_rcv_established+0xa60/0x1a50 net/ipv4/tcp_input.c:5981
 tcp_v4_do_rcv+0x479/0xa60 net/ipv4/tcp_ipv4.c:1660
 sk_backlog_rcv include/net/sock.h:1051 [inline]
 __release_sock+0x1d8/0x4c0 net/core/sock.c:2794
 release_sock+0x5d/0x1c0 net/core/sock.c:3327
 rds_send_xmit+0x1e5d/0x2690 net/rds/send.c:422
 rds_sendmsg+0x1bdf/0x2290 net/rds/send.c:1382
 sock_sendmsg_nosec net/socket.c:705 [inline]
 sock_sendmsg net/socket.c:725 [inline]
 __sys_sendto+0x42e/0x5b0 net/socket.c:2040
 __do_sys_sendto net/socket.c:2052 [inline]
 __se_sys_sendto net/socket.c:2048 [inline]
 __x64_sys_sendto+0xda/0xf0 net/socket.c:2048
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f10e1fc1129
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 15 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f10e1f6e308 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f10e204a4c8 RCX: 00007f10e1fc1129
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000005
RBP: 00007f10e204a4c0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f10e20175c8
R13: 00007fff67bbfe4f R14: 00007f10e1f6e400 R15: 0000000000022000
 </TASK>

Crashes (3):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci-upstream-kasan-gce-smack-root 2022/05/17 09:18 upstream 42226c989789 744a39e2 .config log report syz C possible deadlock in rds_wake_sk_sleep
ci-upstream-linux-next-kasan-gce-root 2022/05/15 21:52 linux-next 1e1b28b936ae 744a39e2 .config log report syz C possible deadlock in rds_wake_sk_sleep
ci-upstream-net-this-kasan-gce 2022/06/15 08:52 net d7dd6eccfbc9 127d1faf .config log report info possible deadlock in rds_wake_sk_sleep