| Title | Replies (including bot) | Last reply |
|---|---|---|
| [syzbot] [net?] possible deadlock in ipv6_sock_mc_close (3) | 0 (1) | 2025/01/06 08:05 |
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| Title | Replies (including bot) | Last reply |
|---|---|---|
| [syzbot] [net?] possible deadlock in ipv6_sock_mc_close (3) | 0 (1) | 2025/01/06 08:05 |
| Kernel | Title | Rank 🛈 | Repro | Cause bisect | Fix bisect | Count | Last | Reported | Patched | Status |
|---|---|---|---|---|---|---|---|---|---|---|
| upstream | possible deadlock in ipv6_sock_mc_close (2) net | 4 | 1 | 464d | 462d | 0/29 | auto-obsoleted due to no activity on 2024/12/10 03:31 | |||
| upstream | possible deadlock in ipv6_sock_mc_close net | 4 | C | done | unreliable | 6 | 1705d | 1743d | 0/29 | closed as invalid on 2023/08/03 10:00 |
| upstream | possible deadlock in ipv6_sock_mc_close (4) net | 4 | C | done | 7 | 3d06h | 1d00h | 0/29 | upstream: reported C repro on 2025/12/08 13:22 |
======================================================
WARNING: possible circular locking dependency detected
6.13.0-rc5-syzkaller-00006-g56e6a3499e14 #0 Not tainted
------------------------------------------------------
syz.2.174/6655 is trying to acquire lock:
ffffffff8fedc988 (rtnl_mutex){+.+.}-{4:4}, at: ipv6_sock_mc_close+0xdb/0x120 net/ipv6/mcast.c:354
but task is already holding lock:
ffff888051730aa8 (&smc->clcsock_release_lock){+.+.}-{4:4}, at: smc_clcsock_release+0x75/0xe0 net/smc/smc_close.c:30
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #2 (&smc->clcsock_release_lock){+.+.}-{4:4}:
__mutex_lock_common kernel/locking/mutex.c:585 [inline]
__mutex_lock+0x19b/0xa60 kernel/locking/mutex.c:735
smc_switch_to_fallback+0x2d/0xa00 net/smc/af_smc.c:903
smc_sendmsg+0x13d/0x520 net/smc/af_smc.c:2778
sock_sendmsg_nosec net/socket.c:711 [inline]
__sock_sendmsg net/socket.c:726 [inline]
____sys_sendmsg+0xaaf/0xc90 net/socket.c:2583
___sys_sendmsg+0x135/0x1e0 net/socket.c:2637
__sys_sendmsg+0x16e/0x220 net/socket.c:2669
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
-> #1 (sk_lock-AF_INET6){+.+.}-{0:0}:
lock_sock_nested+0x3a/0xf0 net/core/sock.c:3622
lock_sock include/net/sock.h:1623 [inline]
sockopt_lock_sock net/core/sock.c:1126 [inline]
sockopt_lock_sock+0x54/0x70 net/core/sock.c:1117
do_ipv6_setsockopt+0x2160/0x4520 net/ipv6/ipv6_sockglue.c:567
ipv6_setsockopt+0xcb/0x170 net/ipv6/ipv6_sockglue.c:993
rawv6_setsockopt+0xd7/0x680 net/ipv6/raw.c:1054
do_sock_setsockopt+0x222/0x480 net/socket.c:2313
__sys_setsockopt+0x1a0/0x230 net/socket.c:2338
__do_sys_setsockopt net/socket.c:2344 [inline]
__se_sys_setsockopt net/socket.c:2341 [inline]
__x64_sys_setsockopt+0xbd/0x160 net/socket.c:2341
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
-> #0 (rtnl_mutex){+.+.}-{4:4}:
check_prev_add kernel/locking/lockdep.c:3161 [inline]
check_prevs_add kernel/locking/lockdep.c:3280 [inline]
validate_chain kernel/locking/lockdep.c:3904 [inline]
__lock_acquire+0x249e/0x3c40 kernel/locking/lockdep.c:5226
lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5849
__mutex_lock_common kernel/locking/mutex.c:585 [inline]
__mutex_lock+0x19b/0xa60 kernel/locking/mutex.c:735
ipv6_sock_mc_close+0xdb/0x120 net/ipv6/mcast.c:354
inet6_release+0x3f/0x70 net/ipv6/af_inet6.c:482
__sock_release net/socket.c:640 [inline]
sock_release+0x8e/0x1d0 net/socket.c:668
smc_clcsock_release+0xb7/0xe0 net/smc/smc_close.c:34
__smc_release+0x5c2/0x880 net/smc/af_smc.c:301
smc_release+0x1fc/0x5f0 net/smc/af_smc.c:344
__sock_release+0xb0/0x270 net/socket.c:640
sock_close+0x1c/0x30 net/socket.c:1408
__fput+0x3f8/0xb60 fs/file_table.c:450
task_work_run+0x14e/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
other info that might help us debug this:
Chain exists of:
rtnl_mutex --> sk_lock-AF_INET6 -->
&smc->clcsock_release_lock
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&smc->clcsock_release_lock);
lock(sk_lock-AF_INET6);
lock(&smc->clcsock_release_lock);
lock(rtnl_mutex);
*** DEADLOCK ***
2 locks held by syz.2.174/6655:
#0: ffff88804b71be08 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:818 [inline]
#0: ffff88804b71be08 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: __sock_release+0x86/0x270 net/socket.c:639
#1: ffff888051730aa8 (&smc->clcsock_release_lock){+.+.}-{4:4}, at: smc_clcsock_release+0x75/0xe0 net/smc/smc_close.c:30
stack backtrace:
CPU: 3 UID: 0 PID: 6655 Comm: syz.2.174 Not tainted 6.13.0-rc5-syzkaller-00006-g56e6a3499e14 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_circular_bug+0x419/0x5d0 kernel/locking/lockdep.c:2074
check_noncircular+0x31a/0x400 kernel/locking/lockdep.c:2206
check_prev_add kernel/locking/lockdep.c:3161 [inline]
check_prevs_add kernel/locking/lockdep.c:3280 [inline]
validate_chain kernel/locking/lockdep.c:3904 [inline]
__lock_acquire+0x249e/0x3c40 kernel/locking/lockdep.c:5226
lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5849
__mutex_lock_common kernel/locking/mutex.c:585 [inline]
__mutex_lock+0x19b/0xa60 kernel/locking/mutex.c:735
ipv6_sock_mc_close+0xdb/0x120 net/ipv6/mcast.c:354
inet6_release+0x3f/0x70 net/ipv6/af_inet6.c:482
__sock_release net/socket.c:640 [inline]
sock_release+0x8e/0x1d0 net/socket.c:668
smc_clcsock_release+0xb7/0xe0 net/smc/smc_close.c:34
__smc_release+0x5c2/0x880 net/smc/af_smc.c:301
smc_release+0x1fc/0x5f0 net/smc/af_smc.c:344
__sock_release+0xb0/0x270 net/socket.c:640
sock_close+0x1c/0x30 net/socket.c:1408
__fput+0x3f8/0xb60 fs/file_table.c:450
task_work_run+0x14e/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe2ec385d29
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffc27879538 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 000000000000e61f RCX: 00007fe2ec385d29
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007fe2ec577ba0 R08: 0000000000000001 R09: 00007ffc2787982f
R10: 00007fe2ec200000 R11: 0000000000000246 R12: 000000000000e688
R13: 00007fe2ec575fa0 R14: 0000000000000032 R15: ffffffffffffffff
</TASK>
| Time | Kernel | Commit | Syzkaller | Config | Log | Report | Syz repro | C repro | VM info | Assets (help?) | Manager | Title |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2025/01/02 07:56 | upstream | 56e6a3499e14 | d3ccff63 | .config | console log | report | info | [disk image (non-bootable)] [vmlinux] [kernel image] | ci-qemu-upstream | possible deadlock in ipv6_sock_mc_close |