syzbot


no output from test machine (5)

Status: fixed on 2020/10/27 00:21
Reported-by: syzbot+e63407b35dff08dbee02@syzkaller.appspotmail.com
Fix commit: d6d1940044d6 Fix a deadlock between uvn_io() and uvn_flush(). While faulting on a page backed by a vnode, uvn_io() will end up being called in order to populate newly allocated pages using I/O on the backing vnode. Before performing the I/O, newly allocated pages are flagged as busy by uvn_get(), that is before uvn_io() tries to lock the vnode. Such pages could then end up being flushed by uvn_flush() which already has acquired the vnode lock. Since such pages are flagged as busy, uvn_flush() will wait for them to be flagged as not busy. This will never happens as uvn_io() cannot make progress until the vnode lock is released.
First crash: 1406d, last: 1308d
Similar bugs (7)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
openbsd no output from test machine (2) C 89865 1427d 1480d 0/3 closed as invalid on 2020/06/30 06:21
openbsd no output from test machine (6) C 2779 1287d 1308d 3/3 fixed on 2020/11/17 21:57
openbsd no output from test machine (8) C 364973 now 664d 0/3 upstream: reported C repro on 2022/08/02 15:56
openbsd no output from test machine (4) syz 14713 1406d 1413d 0/3 closed as invalid on 2020/07/21 11:12
openbsd no output from test machine C 551400 1480d 2055d 3/3 fixed on 2020/05/08 10:08
openbsd no output from test machine (7) C 124310 664d 1287d 3/3 fixed on 2022/08/02 15:51
openbsd no output from test machine (3) C 25293 1413d 1427d 3/3 fixed on 2020/07/14 23:08
Crashes (49467):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/10/20 03:05 openbsd 81b11609be1d ff4a3345 .config console log syz C ci-openbsd-setuid
2020/10/13 02:31 openbsd 0d27d3d93b84 d32b0bbf .config console log syz C ci-openbsd-setuid
2020/09/01 11:17 openbsd e3132ea9152e d5a3ae1f .config console log syz C ci-openbsd-setuid
2020/07/25 11:07 openbsd a9f43bc31f08 0a13649c .config console log syz ci-openbsd-multicore
2020/07/21 19:12 openbsd 38194102e48c 328906f3 .config console log syz ci-openbsd-main
2020/10/26 23:33 openbsd f39681d966fb c62e79ba .config console log ci-openbsd-main
2020/10/26 22:57 openbsd f39681d966fb c62e79ba .config console log ci-openbsd-multicore
2020/10/26 21:47 openbsd f39681d966fb c62e79ba .config console log ci-openbsd-setuid
2020/10/26 20:33 openbsd f39681d966fb c62e79ba .config console log ci-openbsd-setuid
2020/10/26 19:08 openbsd f39681d966fb c62e79ba .config console log ci-openbsd-multicore
2020/10/26 18:24 openbsd f39681d966fb c62e79ba .config console log ci-openbsd-multicore
2020/10/26 17:01 openbsd f39681d966fb c62e79ba .config console log ci-openbsd-multicore
2020/10/26 15:44 openbsd f39681d966fb c62e79ba .config console log ci-openbsd-setuid
2020/10/26 14:42 openbsd f39681d966fb c62e79ba .config console log ci-openbsd-main
2020/10/26 14:32 openbsd f39681d966fb c62e79ba .config console log ci-openbsd-setuid
2020/10/26 13:29 openbsd f39681d966fb c62e79ba .config console log ci-openbsd-multicore
2020/10/26 12:20 openbsd f39681d966fb c62e79ba .config console log ci-openbsd-multicore
2020/10/26 11:08 openbsd f39681d966fb c62e79ba .config console log ci-openbsd-multicore
2020/10/26 11:03 openbsd f39681d966fb c62e79ba .config console log ci-openbsd-multicore
2020/10/26 09:43 openbsd 5d65abadd091 a1839e81 .config console log ci-openbsd-multicore
2020/10/26 08:41 openbsd 5d65abadd091 a1839e81 .config console log ci-openbsd-setuid
2020/10/26 07:41 openbsd 5d65abadd091 a1839e81 .config console log ci-openbsd-setuid
2020/10/26 06:40 openbsd 5d65abadd091 a1839e81 .config console log ci-openbsd-setuid
2020/10/26 05:38 openbsd 5d65abadd091 a1839e81 .config console log ci-openbsd-setuid
2020/10/26 05:13 openbsd 5d65abadd091 a1839e81 .config console log ci-openbsd-multicore
2020/10/26 03:59 openbsd 5d65abadd091 a1839e81 .config console log ci-openbsd-main
2020/10/26 02:54 openbsd 3048029dc92c a1839e81 .config console log ci-openbsd-multicore
2020/10/26 01:44 openbsd 3048029dc92c a1839e81 .config console log ci-openbsd-setuid
2020/10/26 01:04 openbsd 3048029dc92c a1839e81 .config console log ci-openbsd-setuid
2020/10/25 23:47 openbsd 3048029dc92c a1839e81 .config console log ci-openbsd-main
2020/10/25 22:21 openbsd 3048029dc92c a1839e81 .config console log ci-openbsd-multicore
2020/10/25 20:57 openbsd 3048029dc92c a1839e81 .config console log ci-openbsd-multicore
2020/10/25 19:42 openbsd 3048029dc92c a1839e81 .config console log ci-openbsd-multicore
2020/10/25 18:10 openbsd 3048029dc92c a1839e81 .config console log ci-openbsd-multicore
2020/10/25 16:59 openbsd 3048029dc92c a1839e81 .config console log ci-openbsd-multicore
2020/10/25 15:57 openbsd 3048029dc92c a1839e81 .config console log ci-openbsd-multicore
2020/10/25 14:53 openbsd 3048029dc92c a1839e81 .config console log ci-openbsd-setuid
2020/10/25 13:45 openbsd 832971c7e83a a1839e81 .config console log ci-openbsd-setuid
2020/10/25 12:38 openbsd 832971c7e83a a1839e81 .config console log ci-openbsd-setuid
2020/10/25 11:25 openbsd 832971c7e83a a1839e81 .config console log ci-openbsd-setuid
2020/10/25 10:36 openbsd 832971c7e83a a1839e81 .config console log ci-openbsd-main
2020/10/25 09:35 openbsd 832971c7e83a a1839e81 .config console log ci-openbsd-main
2020/10/25 08:22 openbsd 832971c7e83a a1839e81 .config console log ci-openbsd-multicore
2020/10/25 07:33 openbsd 832971c7e83a a1839e81 .config console log ci-openbsd-multicore
2020/10/25 06:16 openbsd 832971c7e83a a1839e81 .config console log ci-openbsd-setuid
2020/10/25 05:15 openbsd 832971c7e83a a1839e81 .config console log ci-openbsd-multicore
2020/10/25 04:20 openbsd 832971c7e83a a1839e81 .config console log ci-openbsd-multicore
2020/10/25 03:17 openbsd 832971c7e83a a1839e81 .config console log ci-openbsd-setuid
2020/07/21 11:13 openbsd 38194102e48c 328906f3 .config console log ci-openbsd-setuid
* Struck through repros no longer work on HEAD.