Hello, syzbot found the following issue on: HEAD commit: 7ee983c850b4 Merge tag 'drm-fixes-2025-02-08' of https://g.. git tree: upstream console+strace: https://syzkaller.appspot.com/x/log.txt?x=107e4bdf980000 kernel config: https://syzkaller.appspot.com/x/.config?x=ec3c160c5cabe70b dashboard link: https://syzkaller.appspot.com/bug?extid=2ff67872645e5b5ebdd5 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=12d1e1b0580000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=14f1ddf8580000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/52091eb5b16c/disk-7ee983c8.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/4aa605b3aa80/vmlinux-7ee983c8.xz kernel image: https://storage.googleapis.com/syzbot-assets/af16dc4bb19a/bzImage-7ee983c8.xz mounted in repro: https://storage.googleapis.com/syzbot-assets/115f05fb40e2/mount_0.gz fsck result: failed (log: https://syzkaller.appspot.com/x/fsck.log?x=10f1ddf8580000) The issue was bisected to: commit 37d11cfc63604b3886308e2111d845d148ced8bc Author: Mateusz Guzik <mjguzik@xxxxxxxxx> Date: Tue Feb 4 21:32:07 2025 +0000 vfs: sanity check the length passed to inode_set_cached_link() bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=12073df8580000 final oops: https://syzkaller.appspot.com/x/report.txt?x=11073df8580000 console output: https://syzkaller.appspot.com/x/log.txt?x=16073df8580000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+2ff67872645e5b5ebdd5@xxxxxxxxxxxxxxxxxxxxxxxxx Fixes: 37d11cfc6360 ("vfs: sanity check the length passed to inode_set_cached_link()") ------------[ cut here ]------------ bad length passed for symlink [/tmp/syz-imagegen2884317625/] (got 39, expected 29) WARNING: CPU: 0 PID: 5828 at ./include/linux/fs.h:802 inode_set_cached_link include/linux/fs.h:802 [inline] WARNING: CPU: 0 PID: 5828 at ./include/linux/fs.h:802 __ext4_iget+0x3aa2/0x4310 fs/ext4/inode.c:5012 Modules linked in: CPU: 0 UID: 0 PID: 5828 Comm: syz-executor385 Not tainted 6.14.0-rc1-syzkaller-00181-g7ee983c850b4 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 RIP: 0010:inode_set_cached_link include/linux/fs.h:802 [inline] RIP: 0010:__ext4_iget+0x3aa2/0x4310 fs/ext4/inode.c:5012 Code: e8 63 19 49 ff c6 05 e9 1a da 0d 01 90 8b 95 10 ff ff ff 44 89 e1 48 c7 c7 40 4b 85 8b 48 8b b5 f8 fe ff ff e8 8f 57 09 ff 90 <0f> 0b 90 90 e9 2d fd ff ff e8 30 57 ab ff e9 f6 e6 ff ff e8 06 56 RSP: 0018:ffffc90003ca7810 EFLAGS: 00010286 RAX: 0000000000000000 RBX: ffff888077bd8ca4 RCX: ffffffff817a1159 RDX: ffff888034e01e00 RSI: ffffffff817a1166 RDI: 0000000000000001 RBP: ffffc90003ca7960 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000001 R12: 000000000000001d R13: 0000000000000000 R14: 0000000000002000 R15: ffff888077bd8c98 FS: 00005555696a5380(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005555696be778 CR3: 00000000743ae000 CR4: 0000000000350ef0 Call Trace: <TASK> ext4_lookup+0x37e/0x730 fs/ext4/namei.c:1813 __lookup_slow+0x252/0x470 fs/namei.c:1793 lookup_slow fs/namei.c:1810 [inline] walk_component+0x350/0x5b0 fs/namei.c:2114 lookup_last fs/namei.c:2612 [inline] path_lookupat+0x17f/0x770 fs/namei.c:2636 filename_lookup+0x221/0x5f0 fs/namei.c:2665 user_path_at+0x3a/0x60 fs/namei.c:3072 ksys_umount fs/namespace.c:2071 [inline] __do_sys_umount fs/namespace.c:2079 [inline] __se_sys_umount fs/namespace.c:2077 [inline] __x64_sys_umount+0x10b/0x1a0 fs/namespace.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 RIP: 0033:0x7fd6ca0f8487 Code: 07 00 48 83 c4 08 5b 5d c3 66 2e 0f 1f 84 00 00 00 00 00 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 b8 ff ff ff f7 d8 64 89 02 b8 RSP: 002b:00007ffd3ce25b68 EFLAGS: 00000202 ORIG_RAX: 00000000000000a6 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fd6ca0f8487 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffd3ce25c20 RBP: 00007ffd3ce25c20 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000202 R12: 00007ffd3ce26d10 R13: 00005555696b6740 R14: 0000000000000001 R15: 431bde82d7b634db </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. 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
