panic: Most recently used by ip6opt

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 0d62ce24 Colemak Mod DH keyboard layout
git tree: freebsd
console output: https://syzkaller.appspot.com/x/log.txt?x=139d4044a00000
dashboard link: https://syzkaller.appspot.com/bug?extid=97a8da4c64ca7b3f1305

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

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+97a8da...@syzkaller.appspotmail.com

panic: Most recently used by ip6opt

cpuid = 0
time = 1000000464
KDB: stack backtrace:
db_trace_self_wrapper() at db_trace_self_wrapper+0x47/frame
0xfffffe00293ee0c0
vpanic() at vpanic+0x1e0/frame 0xfffffe00293ee120
panic() at panic+0x43/frame 0xfffffe00293ee180
mtrash_ctor() at mtrash_ctor+0xed/frame 0xfffffe00293ee1c0
uma_zalloc_arg() at uma_zalloc_arg+0x1036/frame 0xfffffe00293ee270
malloc() at malloc+0xe1/frame 0xfffffe00293ee2e0
softdep_disk_io_initiation() at softdep_disk_io_initiation+0xf56/frame
0xfffffe00293ee390
ffs_geom_strategy() at ffs_geom_strategy+0x23c/frame 0xfffffe00293ee3d0
bufwrite() at bufwrite+0x30f/frame 0xfffffe00293ee420
ffs_update() at ffs_update+0x42d/frame 0xfffffe00293ee4a0
ffs_syncvnode() at ffs_syncvnode+0x6f7/frame 0xfffffe00293ee530
ffs_truncate() at ffs_truncate+0xa71/frame 0xfffffe00293ee720
ufs_setattr() at ufs_setattr+0x918/frame 0xfffffe00293ee7c0
VOP_SETATTR_APV() at VOP_SETATTR_APV+0xc2/frame 0xfffffe00293ee7f0
vn_truncate() at vn_truncate+0x23f/frame 0xfffffe00293ee930
kern_ftruncate() at kern_ftruncate+0x13b/frame 0xfffffe00293ee980
amd64_syscall() at amd64_syscall+0x436/frame 0xfffffe00293eeab0
fast_syscall_common() at fast_syscall_common+0x101/frame 0xfffffe00293eeab0
--- syscall (198, FreeBSD ELF64, nosys), rip = 0x41309a, rsp =
0x7fffdfffdf38, rbp = 0x2 ---
KDB: enter: panic
[ thread pid 7055 tid 101825 ]
Stopped at kdb_enter+0x6a: movq $0,kdb_why


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.