Hello, syzbot found the following issue on: HEAD commit: 69b8923f5003 Merge tag 'for-linus-6.14-ofs4' of git://git... git tree: upstream console+strace: https://syzkaller.appspot.com/x/log.txt?x=14fbdddf980000 kernel config: https://syzkaller.appspot.com/x/.config?x=57ab43c279fa614d dashboard link: https://syzkaller.appspot.com/bug?extid=ab57f676a518849a8d57 compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=15da95f8580000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=165f8b24580000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/ea84ac864e92/disk-69b8923f.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/6a465997b4e0/vmlinux-69b8923f.xz kernel image: https://storage.googleapis.com/syzbot-assets/d72b67b2bd15/bzImage-69b8923f.xz mounted in repro: https://storage.googleapis.com/syzbot-assets/7d96d510aa23/mount_0.gz The issue was bisected to: commit 30d61efe118cad1a73ad2ad66a3298e4abdf9f41 Author: Al Viro <viro@xxxxxxxxxxxxxxxxxx> Date: Mon Jan 6 02:33:17 2025 +0000 9p: fix ->rename_sem exclusion bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=148b7b64580000 final oops: https://syzkaller.appspot.com/x/report.txt?x=168b7b64580000 console output: https://syzkaller.appspot.com/x/log.txt?x=128b7b64580000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+ab57f676a518849a8d57@xxxxxxxxxxxxxxxxxxxxxxxxx Fixes: 30d61efe118c ("9p: fix ->rename_sem exclusion") Oops: general protection fault, probably for non-canonical address 0xdffffc000000000d: 0000 [#1] PREEMPT SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000068-0x000000000000006f] CPU: 0 UID: 0 PID: 5821 Comm: syz-executor287 Not tainted 6.13.0-syzkaller-09793-g69b8923f5003 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 RIP: 0010:__d_unalias+0x199/0x2a0 fs/dcache.c:2969 Code: 98 00 00 00 4c 89 fb 48 c1 eb 03 49 89 ed 80 3c 2b 00 74 08 4c 89 ff e8 65 62 e7 ff 49 8b 2f 48 83 c5 68 48 89 e8 48 c1 e8 03 <42> 80 3c 28 00 74 08 48 89 ef e8 48 62 e7 ff 4c 8b 5d 00 4d 85 db RSP: 0018:ffffc90003d9fa98 EFLAGS: 00010202 RAX: 000000000000000d RBX: 1ffff1100996cb61 RCX: ffff88804d821e00 RDX: 0000000000000000 RSI: ffff88804cb65a70 RDI: ffff88804cb658f8 RBP: 0000000000000068 R08: ffff88804e530f6b R09: 1ffff11009ca61ed R10: dffffc0000000000 R11: ffffed1009ca61ee R12: ffff88804cb65a70 R13: dffffc0000000000 R14: 0000000000000000 R15: ffff88804cb65b08 FS: 000055555b892380(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffe074ff000 CR3: 0000000078440000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> d_splice_alias+0x1e6/0x330 fs/dcache.c:3037 nilfs_lookup+0x1c2/0x2a0 fs/nilfs2/namei.c:77 lookup_one_qstr_excl+0x126/0x2b0 fs/namei.c:1693 do_renameat2+0x706/0x13f0 fs/namei.c:5176 __do_sys_rename fs/namei.c:5273 [inline] __se_sys_rename fs/namei.c:5271 [inline] __x64_sys_rename+0x82/0x90 fs/namei.c:5271 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: 0033:0x7f7cc482fad9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 17 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:00007ffe074fe328 EFLAGS: 00000246 ORIG_RAX: 0000000000000052 RAX: ffffffffffffffda RBX: 00007f7cc4878fc8 RCX: 00007f7cc482fad9 RDX: 0000000000000000 RSI: 0000000020000800 RDI: 00000000200001c0 RBP: 00007f7cc48a35f0 R08: 000055555b8934c0 R09: 000055555b8934c0 R10: 000055555b8934c0 R11: 0000000000000246 R12: 00007ffe074fe350 R13: 00007ffe074fe578 R14: 431bde82d7b634db R15: 00007f7cc487803b </TASK> Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:__d_unalias+0x199/0x2a0 fs/dcache.c:2969 Code: 98 00 00 00 4c 89 fb 48 c1 eb 03 49 89 ed 80 3c 2b 00 74 08 4c 89 ff e8 65 62 e7 ff 49 8b 2f 48 83 c5 68 48 89 e8 48 c1 e8 03 <42> 80 3c 28 00 74 08 48 89 ef e8 48 62 e7 ff 4c 8b 5d 00 4d 85 db RSP: 0018:ffffc90003d9fa98 EFLAGS: 00010202 RAX: 000000000000000d RBX: 1ffff1100996cb61 RCX: ffff88804d821e00 RDX: 0000000000000000 RSI: ffff88804cb65a70 RDI: ffff88804cb658f8 RBP: 0000000000000068 R08: ffff88804e530f6b R09: 1ffff11009ca61ed R10: dffffc0000000000 R11: ffffed1009ca61ee R12: ffff88804cb65a70 R13: dffffc0000000000 R14: 0000000000000000 R15: ffff88804cb65b08 FS: 000055555b892380(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffe074ff000 CR3: 0000000078440000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 98 cwtl 1: 00 00 add %al,(%rax) 3: 00 4c 89 fb add %cl,-0x5(%rcx,%rcx,4) 7: 48 c1 eb 03 shr $0x3,%rbx b: 49 89 ed mov %rbp,%r13 e: 80 3c 2b 00 cmpb $0x0,(%rbx,%rbp,1) 12: 74 08 je 0x1c 14: 4c 89 ff mov %r15,%rdi 17: e8 65 62 e7 ff call 0xffe76281 1c: 49 8b 2f mov (%r15),%rbp 1f: 48 83 c5 68 add $0x68,%rbp 23: 48 89 e8 mov %rbp,%rax 26: 48 c1 e8 03 shr $0x3,%rax * 2a: 42 80 3c 28 00 cmpb $0x0,(%rax,%r13,1) <-- trapping instruction 2f: 74 08 je 0x39 31: 48 89 ef mov %rbp,%rdi 34: e8 48 62 e7 ff call 0xffe76281 39: 4c 8b 5d 00 mov 0x0(%rbp),%r11 3d: 4d 85 db test %r11,%r11 --- 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. For information about bisection process see: https://goo.gl/tpsmEJ#bisection If the report is already addressed, 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 report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup
