Hello, syzbot found the following issue on: HEAD commit: 7cb1b4663150 Merge tag 'locking_urgent_for_v6.13_rc3' of g.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=1617eb30580000 kernel config: https://syzkaller.appspot.com/x/.config?x=99a5586995ec03b2 dashboard link: https://syzkaller.appspot.com/bug?extid=95ba71e75926e4a97806 compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/1d137a327f35/disk-7cb1b466.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/14581a57cb27/vmlinux-7cb1b466.xz kernel image: https://storage.googleapis.com/syzbot-assets/22586b0e9bbc/bzImage-7cb1b466.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+95ba71e75926e4a97806@xxxxxxxxxxxxxxxxxxxxxxxxx ====================================================== WARNING: possible circular locking dependency detected 6.13.0-rc2-syzkaller-00018-g7cb1b4663150 #0 Not tainted ------------------------------------------------------ syz.5.1757/14440 is trying to acquire lock: ffff88807f80c658 (sk_lock-AF_INET/1){+.+.}-{0:0}, at: sctp_sock_migrate+0x987/0x1270 net/sctp/socket.c:9655 but task is already holding lock: ffff88807f80dfd8 (sk_lock-AF_INET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1617 [inline] ffff88807f80dfd8 (sk_lock-AF_INET){+.+.}-{0:0}, at: sctp_accept+0x90/0x800 net/sctp/socket.c:4863 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (sk_lock-AF_INET){+.+.}-{0:0}: lock_sock_nested+0x3a/0xf0 net/core/sock.c:3622 lock_sock include/net/sock.h:1617 [inline] sockopt_lock_sock net/core/sock.c:1126 [inline] sockopt_lock_sock+0x54/0x70 net/core/sock.c:1117 do_ip_getsockopt+0x115c/0x2bf0 net/ipv4/ip_sockglue.c:1703 ip_getsockopt+0x9c/0x1e0 net/ipv4/ip_sockglue.c:1765 raw_getsockopt+0x4d/0x1e0 net/ipv4/raw.c:865 do_sock_getsockopt+0x3fe/0x870 net/socket.c:2374 __sys_getsockopt+0x12f/0x260 net/socket.c:2403 __do_sys_getsockopt net/socket.c:2410 [inline] __se_sys_getsockopt net/socket.c:2407 [inline] __x64_sys_getsockopt+0xbd/0x160 net/socket.c:2407 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 -> #2 (rtnl_mutex){+.+.}-{4:4}: __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x19b/0xa60 kernel/locking/mutex.c:735 smc_vlan_by_tcpsk+0x251/0x620 net/smc/smc_core.c:1898 __smc_connect+0x466/0x4890 net/smc/af_smc.c:1517 smc_connect+0x2fc/0x760 net/smc/af_smc.c:1693 __sys_connect_file+0x13e/0x1a0 net/socket.c:2055 __sys_connect+0x14f/0x170 net/socket.c:2074 __do_sys_connect net/socket.c:2080 [inline] __se_sys_connect net/socket.c:2077 [inline] __x64_sys_connect+0x72/0xb0 net/socket.c:2077 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_SMC){+.+.}-{0:0}: lock_sock_nested+0x3a/0xf0 net/core/sock.c:3622 lock_sock include/net/sock.h:1617 [inline] smc_close_non_accepted+0x80/0x200 net/smc/af_smc.c:1832 smc_close_cleanup_listen net/smc/smc_close.c:45 [inline] smc_close_active+0xc3c/0x1070 net/smc/smc_close.c:225 __smc_release+0x634/0x880 net/smc/af_smc.c:277 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 exit_task_work include/linux/task_work.h:43 [inline] do_exit+0xadd/0x2d70 kernel/exit.c:938 do_group_exit+0xd3/0x2a0 kernel/exit.c:1087 get_signal+0x2576/0x2610 kernel/signal.c:3017 arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [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+0x150/0x2a0 kernel/entry/common.c:218 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (sk_lock-AF_INET/1){+.+.}-{0:0}: 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 lock_sock_nested+0x3a/0xf0 net/core/sock.c:3622 sctp_sock_migrate+0x987/0x1270 net/sctp/socket.c:9655 sctp_accept+0x654/0x800 net/sctp/socket.c:4899 inet_accept+0xc4/0x180 net/ipv4/af_inet.c:781 do_accept+0x337/0x530 net/socket.c:1941 __sys_accept4_file net/socket.c:1981 [inline] __sys_accept4+0xfe/0x1b0 net/socket.c:2010 __do_sys_accept net/socket.c:2023 [inline] __se_sys_accept net/socket.c:2020 [inline] __x64_sys_accept+0x74/0xb0 net/socket.c:2020 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 other info that might help us debug this: Chain exists of: sk_lock-AF_INET/1 --> rtnl_mutex --> sk_lock-AF_INET Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(sk_lock-AF_INET); lock(rtnl_mutex); lock(sk_lock-AF_INET); lock(sk_lock-AF_INET/1); *** DEADLOCK *** 1 lock held by syz.5.1757/14440: #0: ffff88807f80dfd8 (sk_lock-AF_INET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1617 [inline] #0: ffff88807f80dfd8 (sk_lock-AF_INET){+.+.}-{0:0}, at: sctp_accept+0x90/0x800 net/sctp/socket.c:4863 stack backtrace: CPU: 1 UID: 0 PID: 14440 Comm: syz.5.1757 Not tainted 6.13.0-rc2-syzkaller-00018-g7cb1b4663150 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: <TASK> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_circular_bug+0x41c/0x610 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 lock_sock_nested+0x3a/0xf0 net/core/sock.c:3622 sctp_sock_migrate+0x987/0x1270 net/sctp/socket.c:9655 sctp_accept+0x654/0x800 net/sctp/socket.c:4899 inet_accept+0xc4/0x180 net/ipv4/af_inet.c:781 do_accept+0x337/0x530 net/socket.c:1941 __sys_accept4_file net/socket.c:1981 [inline] __sys_accept4+0xfe/0x1b0 net/socket.c:2010 __do_sys_accept net/socket.c:2023 [inline] __se_sys_accept net/socket.c:2020 [inline] __x64_sys_accept+0x74/0xb0 net/socket.c:2020 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 RIP: 0033:0x7f530297ff19 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:00007f530381f058 EFLAGS: 00000246 ORIG_RAX: 000000000000002b RAX: ffffffffffffffda RBX: 00007f5302b46080 RCX: 00007f530297ff19 RDX: 0000000020000140 RSI: 0000000020000100 RDI: 0000000000000003 RBP: 00007f53029f3cc8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f5302b46080 R15: 00007fff22fccd28 </TASK> can: request_module (can-proto-4) failed. --- This report is generated by a bot. 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