Hello, syzbot found the following issue on: HEAD commit: 65d6e954e378 Merge tag 'gfs2-v6.5-rc5-fixes' of git://git... git tree: upstream console+strace: https://syzkaller.appspot.com/x/log.txt?x=142177f4680000 kernel config: https://syzkaller.appspot.com/x/.config?x=b273cdfbc13e9a4b dashboard link: https://syzkaller.appspot.com/bug?extid=62cbf263225ae13ff153 compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=11f37a0c680000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=10034f3fa80000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/74df7181e630/disk-65d6e954.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/8455d5988dfe/vmlinux-65d6e954.xz kernel image: https://storage.googleapis.com/syzbot-assets/8ee7b79f0dfd/bzImage-65d6e954.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+62cbf263225ae13ff153@xxxxxxxxxxxxxxxxxxxxxxxxx ------------[ cut here ]------------ WARNING: CPU: 1 PID: 5042 at net/ipv6/ip6_output.c:1800 __ip6_append_data.isra.0+0x1be8/0x47f0 net/ipv6/ip6_output.c:1800 Modules linked in: CPU: 1 PID: 5042 Comm: syz-executor133 Not tainted 6.5.0-syzkaller-11938-g65d6e954e378 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023 RIP: 0010:__ip6_append_data.isra.0+0x1be8/0x47f0 net/ipv6/ip6_output.c:1800 Code: db f6 ff ff e8 09 d5 97 f8 49 8d 44 24 ff 48 89 44 24 60 49 8d 6c 24 07 e9 c2 f6 ff ff 4c 8b b4 24 90 01 00 00 e8 e8 d4 97 f8 <0f> 0b 48 8b 44 24 10 45 89 f4 48 8d 98 74 02 00 00 e8 d2 d4 97 f8 RSP: 0018:ffffc90003a1f3b8 EFLAGS: 00010293 RAX: 0000000000000000 RBX: 0000000000001004 RCX: 0000000000000000 RDX: ffff88801fe70000 RSI: ffffffff88efcf18 RDI: 0000000000000006 RBP: 0000000000001000 R08: 0000000000000006 R09: 0000000000001004 R10: 0000000000001000 R11: 0000000000000000 R12: 0000000000000001 R13: dffffc0000000000 R14: 0000000000001004 R15: ffff888019f31000 FS: 0000555557280380(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000045ad50 CR3: 0000000072666000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> ip6_append_data+0x1e6/0x510 net/ipv6/ip6_output.c:1895 l2tp_ip6_sendmsg+0xdf9/0x1cc0 net/l2tp/l2tp_ip6.c:631 inet_sendmsg+0x9d/0xe0 net/ipv4/af_inet.c:840 sock_sendmsg_nosec net/socket.c:730 [inline] sock_sendmsg+0xd9/0x180 net/socket.c:753 splice_to_socket+0xade/0x1010 fs/splice.c:881 do_splice_from fs/splice.c:933 [inline] direct_splice_actor+0x118/0x180 fs/splice.c:1142 splice_direct_to_actor+0x347/0xa30 fs/splice.c:1088 do_splice_direct+0x1af/0x280 fs/splice.c:1194 do_sendfile+0xb88/0x1390 fs/read_write.c:1254 __do_sys_sendfile64 fs/read_write.c:1322 [inline] __se_sys_sendfile64 fs/read_write.c:1308 [inline] __x64_sys_sendfile64+0x1d6/0x220 fs/read_write.c:1308 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f6b11150469 Code: 48 83 c4 28 c3 e8 37 17 00 00 0f 1f 80 00 00 00 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fffd14e71a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007fffd14e7378 RCX: 00007f6b11150469 RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000005 RBP: 00007f6b111c3610 R08: 00007fffd14e7378 R09: 00007fffd14e7378 R10: 000000010000a006 R11: 0000000000000246 R12: 0000000000000001 R13: 00007fffd14e7368 R14: 0000000000000001 R15: 0000000000000001 </TASK> --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. If the bug is already fixed, let syzbot know by replying with: #syz fix: exact-commit-title If you want syzbot to run the reproducer, reply with: #syz test: git://repo/address.git branch-or-commit-hash If you attach or paste a git patch, syzbot will apply it before testing. If you want to overwrite bug's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the bug is a duplicate of another bug, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup