Hello, syzbot found the following issue on: HEAD commit: 185d72112b95 net: xilinx: axienet: Enable multicast by def.. git tree: net-next console output: https://syzkaller.appspot.com/x/log.txt?x=13e0ec8e980000 kernel config: https://syzkaller.appspot.com/x/.config?x=e78fc116033e0ab7 dashboard link: https://syzkaller.appspot.com/bug?extid=c75d1de73d3b8b76272f compiler: Debian clang version 15.0.6, 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/e84f50e44254/disk-185d7211.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/df64b575cc01/vmlinux-185d7211.xz kernel image: https://storage.googleapis.com/syzbot-assets/16ad5d1d433b/bzImage-185d7211.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+c75d1de73d3b8b76272f@xxxxxxxxxxxxxxxxxxxxxxxxx syz-executor.2[7759] is installing a program with bpf_probe_write_user helper that may corrupt user memory! syz-executor.2[7759] is installing a program with bpf_probe_write_user helper that may corrupt user memory! ====================================================== WARNING: possible circular locking dependency detected 6.10.0-rc4-syzkaller-00869-g185d72112b95 #0 Not tainted ------------------------------------------------------ syz-executor.2/7759 is trying to acquire lock: ffffffff8f5e6f48 (rtnl_mutex){+.+.}-{3:3}, at: smc_vlan_by_tcpsk+0x399/0x4e0 net/smc/smc_core.c:1853 but task is already holding lock: ffff88801bed0258 (sk_lock-AF_INET6){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1602 [inline] ffff88801bed0258 (sk_lock-AF_INET6){+.+.}-{0:0}, at: smc_connect+0xb7/0xde0 net/smc/af_smc.c:1650 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (sk_lock-AF_INET6){+.+.}-{0:0}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 lock_sock_nested+0x48/0x100 net/core/sock.c:3543 do_ipv6_setsockopt+0xbf3/0x3630 net/ipv6/ipv6_sockglue.c:567 ipv6_setsockopt+0x5c/0x1a0 net/ipv6/ipv6_sockglue.c:993 do_sock_setsockopt+0x3af/0x720 net/socket.c:2312 __sys_setsockopt+0x1ae/0x250 net/socket.c:2335 __do_sys_setsockopt net/socket.c:2344 [inline] __se_sys_setsockopt net/socket.c:2341 [inline] __x64_sys_setsockopt+0xb5/0xd0 net/socket.c:2341 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (rtnl_mutex){+.+.}-{3:3}: check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain+0x18e0/0x5900 kernel/locking/lockdep.c:3869 __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 __mutex_lock_common kernel/locking/mutex.c:608 [inline] __mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752 smc_vlan_by_tcpsk+0x399/0x4e0 net/smc/smc_core.c:1853 __smc_connect+0x2a4/0x1890 net/smc/af_smc.c:1522 smc_connect+0x868/0xde0 net/smc/af_smc.c:1702 __sys_connect_file net/socket.c:2049 [inline] __sys_connect+0x2df/0x310 net/socket.c:2066 __do_sys_connect net/socket.c:2076 [inline] __se_sys_connect net/socket.c:2073 [inline] __x64_sys_connect+0x7a/0x90 net/socket.c:2073 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(sk_lock-AF_INET6); lock(rtnl_mutex); lock(sk_lock-AF_INET6); lock(rtnl_mutex); *** DEADLOCK *** 1 lock held by syz-executor.2/7759: #0: ffff88801bed0258 (sk_lock-AF_INET6){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1602 [inline] #0: ffff88801bed0258 (sk_lock-AF_INET6){+.+.}-{0:0}, at: smc_connect+0xb7/0xde0 net/smc/af_smc.c:1650 stack backtrace: CPU: 1 PID: 7759 Comm: syz-executor.2 Not tainted 6.10.0-rc4-syzkaller-00869-g185d72112b95 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2187 check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain+0x18e0/0x5900 kernel/locking/lockdep.c:3869 __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 __mutex_lock_common kernel/locking/mutex.c:608 [inline] __mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752 smc_vlan_by_tcpsk+0x399/0x4e0 net/smc/smc_core.c:1853 __smc_connect+0x2a4/0x1890 net/smc/af_smc.c:1522 smc_connect+0x868/0xde0 net/smc/af_smc.c:1702 __sys_connect_file net/socket.c:2049 [inline] __sys_connect+0x2df/0x310 net/socket.c:2066 __do_sys_connect net/socket.c:2076 [inline] __se_sys_connect net/socket.c:2073 [inline] __x64_sys_connect+0x7a/0x90 net/socket.c:2073 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f0b3687d0a9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 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 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f0b3764b0c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002a RAX: ffffffffffffffda RBX: 00007f0b369b3f80 RCX: 00007f0b3687d0a9 RDX: 000000000000001c RSI: 00000000200000c0 RDI: 000000000000000a RBP: 00007f0b368ec074 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f0b369b3f80 R15: 00007fff165a7738 </TASK> --- This report is generated by a bot. 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