syzbot


WARNING in nsfs_fh_to_dentry

Status: upstream: reported C repro on 2025/09/20 00:13
Subsystems: nfs
[Documentation on labels]
Reported-by: syzbot+9eefe09bedd093f156c2@syzkaller.appspotmail.com
First crash: 5h42m, last: 4h03m
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [nfs?] WARNING in nsfs_fh_to_dentry 0 (1) 2025/09/20 00:13

Sample crash report:
------------[ cut here ]------------
WARNING: fs/nsfs.c:493 at nsfs_fh_to_dentry+0xcc5/0xdc0 fs/nsfs.c:493, CPU#1: syz.0.17/6050
Modules linked in:
CPU: 1 UID: 0 PID: 6050 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:nsfs_fh_to_dentry+0xcc5/0xdc0 fs/nsfs.c:493
Code: 7c 24 60 e9 10 f8 ff ff e8 48 01 79 ff 90 0f 0b 90 e9 09 f6 ff ff e8 3a 01 79 ff 90 0f 0b 90 e9 81 f6 ff ff e8 2c 01 79 ff 90 <0f> 0b 90 e9 d0 f6 ff ff e8 1e 01 79 ff 45 31 ff e9 d9 f7 ff ff e8
RSP: 0018:ffffc90002f97a20 EFLAGS: 00010293
RAX: ffffffff824717f4 RBX: 00000000effffffd RCX: ffff888031990000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000effffffd
RBP: ffffc90002f97b10 R08: ffffffff8fe4db77 R09: 1ffffffff1fc9b6e
R10: dffffc0000000000 R11: fffffbfff1fc9b6f R12: 1ffff920005f2f4c
R13: ffff888028d74894 R14: dffffc0000000000 R15: 0000000000000000
FS:  0000555569cd2500(0000) GS:ffff8881258a2000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b32363fff CR3: 0000000028a1e000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 exportfs_decode_fh_raw+0x178/0x6e0 fs/exportfs/expfs.c:456
 do_handle_to_path+0xa4/0x1a0 fs/fhandle.c:276
 handle_to_path fs/fhandle.c:400 [inline]
 do_handle_open+0x6b4/0x8f0 fs/fhandle.c:415
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1a5d78ec29
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:00007ffff390c9e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000130
RAX: ffffffffffffffda RBX: 00007f1a5d9d5fa0 RCX: 00007f1a5d78ec29
RDX: 0000000000400040 RSI: 0000200000000000 RDI: 0000000000000003
RBP: 00007f1a5d811e41 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1a5d9d5fa0 R14: 00007f1a5d9d5fa0 R15: 0000000000000003
 </TASK>

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/09/19 23:30 linux-next 846bd2225ec3 67c37560 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in nsfs_fh_to_dentry
2025/09/19 22:51 linux-next 846bd2225ec3 67c37560 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in nsfs_fh_to_dentry
2025/09/19 22:22 linux-next 846bd2225ec3 67c37560 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in nsfs_fh_to_dentry
2025/09/19 21:54 linux-next 846bd2225ec3 67c37560 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in nsfs_fh_to_dentry
2025/09/19 21:51 linux-next 846bd2225ec3 67c37560 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in nsfs_fh_to_dentry
* Struck through repros no longer work on HEAD.