panic: Most recently used by tty

Status: fixed on 2019/07/05 06:10
Reported-by: syzbot+c9b6206303bf47bac87e@syzkaller.appspotmail.com
Fix commit: 6a01874c5afa Defer funsetown() calls for a TTY to tty_rel_free().
First crash: 2659d, last: 2645d

Sample crash report:
panic: Most recently used by tty

cpuid = 0
time = 1558234948
KDB: stack backtrace:
db_trace_self_wrapper() at db_trace_self_wrapper+0x47/frame 0xfffffe002109f690
vpanic() at vpanic+0x1e0/frame 0xfffffe002109f6f0
panic() at panic+0x43/frame 0xfffffe002109f750
mtrash_ctor() at mtrash_ctor+0xed/frame 0xfffffe002109f790
uma_zalloc_arg() at uma_zalloc_arg+0x1036/frame 0xfffffe002109f840
malloc() at malloc+0xe1/frame 0xfffffe002109f8b0
tty_alloc_mutex() at tty_alloc_mutex+0x22c/frame 0xfffffe002109f8e0
pts_alloc() at pts_alloc+0x179/frame 0xfffffe002109f930
sys_posix_openpt() at sys_posix_openpt+0x94/frame 0xfffffe002109f970
ia32_syscall() at ia32_syscall+0x452/frame 0xfffffe002109fab0
int0x80_syscall_common() at int0x80_syscall_common+0x9c/frame 0xa
KDB: enter: panic
[ thread pid 788 tid 100116 ]
Stopped at      kdb_enter+0x6a: movq    $0,kdb_why

Crashes (24):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/05/19 03:05 freebsd e2abb7b27ea6 40046286 console log report syz ci-freebsd-main
2019/05/18 17:00 freebsd e2abb7b27ea6 40046286 console log report syz ci-freebsd-main
2019/05/18 11:09 freebsd e2abb7b27ea6 40046286 console log report syz ci-freebsd-main
2019/05/13 12:12 freebsd 9c5c2e43352d 16ab1e89 console log report syz ci-freebsd-main
2019/05/13 11:25 freebsd 9c5c2e43352d 16ab1e89 console log report syz ci-freebsd-main
2019/05/10 23:57 freebsd fbc304aae0ef 46caad94 console log report syz ci-freebsd-main
2019/05/10 11:48 freebsd 23ca26e1d654 018207ef console log report syz ci-freebsd-main
2019/05/08 13:01 freebsd 5446f43efb61 a7383bfa console log report syz ci-freebsd-main
2019/05/23 03:33 freebsd e2abb7b27ea6 40046286 console log report ci-freebsd-main
2019/05/22 20:59 freebsd e2abb7b27ea6 40046286 console log report ci-freebsd-main
2019/05/22 04:29 freebsd e2abb7b27ea6 40046286 console log report ci-freebsd-main
2019/05/22 04:16 freebsd e2abb7b27ea6 40046286 console log report ci-freebsd-main
2019/05/20 17:56 freebsd e2abb7b27ea6 40046286 console log report ci-freebsd-main
2019/05/20 04:51 freebsd e2abb7b27ea6 40046286 console log report ci-freebsd-main
2019/05/19 20:41 freebsd e2abb7b27ea6 40046286 console log report ci-freebsd-main
2019/05/19 02:29 freebsd e2abb7b27ea6 40046286 console log report ci-freebsd-main
2019/05/18 16:26 freebsd e2abb7b27ea6 40046286 console log report ci-freebsd-main
2019/05/18 10:36 freebsd e2abb7b27ea6 40046286 console log report ci-freebsd-main
2019/05/13 11:34 freebsd 9c5c2e43352d 16ab1e89 console log report ci-freebsd-main
2019/05/13 10:57 freebsd 9c5c2e43352d 16ab1e89 console log report ci-freebsd-main
2019/05/12 01:51 freebsd 24c307c3c0ca 0637a7f0 console log report ci-freebsd-main
2019/05/10 23:23 freebsd fbc304aae0ef 46caad94 console log report ci-freebsd-main
2019/05/10 11:26 freebsd 23ca26e1d654 018207ef console log report ci-freebsd-main
2019/05/08 12:07 freebsd 5446f43efb61 a7383bfa console log report ci-freebsd-main
* Struck through repros no longer work on HEAD.