panic: ffs_fsync: not dirty

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: d11f3b71804f When rewriting an ELF header (i.e. in strip a..
git tree: openbsd
console output: https://syzkaller.appspot.com/x/log.txt?x=16a390cb180000
kernel config: https://syzkaller.appspot.com/x/.config?x=7058272de1526588
dashboard link: https://syzkaller.appspot.com/bug?extid=b51d6659984cb432d4ee

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/283412e0304a/disk-d11f3b71.raw.xz
bsd.gdb: https://storage.googleapis.com/syzbot-assets/4e826862c479/bsd-d11f3b71.gdb.xz
kernel image: https://storage.googleapis.com/syzbot-assets/be10a8cba7b2/kernel-d11f3b71.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+b51d66...@syzkaller.appspotmail.com

login: panic: ffs_fsync: not dirty
Starting stack trace...
panic(ffffffff8293126f) at panic+0x16f sys/kern/subr_prf.c:229
ffs_fsync(ffff800037452670) at ffs_fsync+0x387 sys/ufs/ffs/ffs_vnops.c:447
VOP_FSYNC(fffffd80598ccce0,fffffd807f7d7548,2,ffff8000fffec2c8) at VOP_FSYNC+0xcf sys/kern/vfs_vops.c:311
ffs_sync_vnode(fffffd80598ccce0,ffff8000374527a8) at ffs_sync_vnode+0x16b sys/ufs/ffs/ffs_vfsops.c:1081
vfs_mount_foreach_vnode(ffff8000006d2400,ffffffff826716b0,ffff8000374527a8) at vfs_mount_foreach_vnode+0x55 sys/kern/vfs_subr.c:910
ffs_sync(ffff8000006d2400,2,0,fffffd807f7d7548,ffff8000fffec2c8) at ffs_sync+0x104 sys/ufs/ffs/ffs_vfsops.c:1131
sys_sync(ffff8000fffec2c8,ffff800037452990,ffff8000374528e0) at sys_sync+0xbc sys/kern/vfs_syscalls.c:536
syscall(ffff800037452990) at syscall+0x854 mi_syscall sys/sys/syscall_mi.h:180 [inline]
syscall(ffff800037452990) at syscall+0x854 sys/arch/amd64/amd64/trap.c:577
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0xa7c5d2717b0, count: 248
End of stack trace.


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