syzbot


kernel: double fault trap, code=0 (4)
Status: fixed on 2021/01/09 22:01
Reported-by: syzbot+a43ace363f1b663238f8@syzkaller.appspotmail.com
Fix commit: c11d76984715 Syzkaller has found a stack overflow in socket splicing. Broadcast packets were resent through simplex broadcast delivery and socket splicing. Although there is an M_LOOP check in somove(9), it did not take effect. if_input_local() cleared the M_BCAST and M_MCAST flags with m_resethdr(). As if_input_local() is used for broadcast and multicast delivery, it was a mistake to delete them. Keep the M_BCAST and M_MCAST mbuf flags when packets are reinjected into the network stack. Reported-by: syzbot+a43ace363f1b663238f8@syzkaller.appspotmail.com OK anton@; discussed with claudio@
First crash: 466d, last: 209d
similar bugs (3):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
openbsd kernel: double fault trap, code=0 (2) syz 2 632d 632d 0/3 closed as invalid on 2020/02/21 15:02
openbsd kernel: double fault trap, code=0 (3) C 69 499d 508d 3/3 fixed on 2020/03/12 12:20
openbsd kernel: double fault trap, code=0 1 800d 800d 0/3 auto-closed as invalid on 2019/10/25 08:51
Patch testing requests:
Created Duration User Patch Repo Result
2021/01/03 08:53 15m anton@basename.se https://github.com/mptre/openbsd-src splice OK
2020/04/18 08:55 17m anton@basename.se https://github.com/mptre/openbsd-src netinet OK

Sample crash report:

Crashes (493):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci-openbsd-main 2020/04/16 00:19 openbsd 20c8eb7cf336 3f3c5574 .config log report syz C
ci-openbsd-main 2020/04/14 13:36 openbsd 25b10e5944a3 3f3c5574 .config log report syz
ci-openbsd-setuid 2020/12/27 13:42 openbsd 6a98cd60999d b982b3ea .config log report
ci-openbsd-setuid 2020/12/07 08:04 openbsd 14f2141b3532 57072f7b .config log report
ci-openbsd-setuid 2020/11/20 09:41 openbsd c968ca6e72d6 0767f13f .config log report
ci-openbsd-setuid 2020/08/11 06:23 openbsd 5e0cad520542 d3694ffb .config log report
ci-openbsd-setuid 2020/08/11 01:38 openbsd 5e0cad520542 d3694ffb .config log report
ci-openbsd-setuid 2020/08/10 15:46 openbsd 3c86a58ec715 7adc7b65 .config log report
ci-openbsd-setuid 2020/08/10 06:54 openbsd 3c86a58ec715 70301872 .config log report
ci-openbsd-setuid 2020/08/10 04:15 openbsd ec4d335cab8e 70301872 .config log report
ci-openbsd-setuid 2020/08/09 12:13 openbsd 97da2ad2205f f721e4a0 .config log report
ci-openbsd-setuid 2020/08/09 04:44 openbsd a395eaf7c290 f721e4a0 .config log report
ci-openbsd-setuid 2020/08/08 18:16 openbsd a395eaf7c290 f721e4a0 .config log report
ci-openbsd-setuid 2020/08/08 02:30 openbsd 42858fb0ce8a bb468f32 .config log report
ci-openbsd-setuid 2020/08/07 22:24 openbsd 42858fb0ce8a bb468f32 .config log report
ci-openbsd-setuid 2020/08/07 20:11 openbsd 42858fb0ce8a bb468f32 .config log report
ci-openbsd-multicore 2020/08/07 19:03 openbsd 42858fb0ce8a bb468f32 .config log report
ci-openbsd-setuid 2020/08/07 07:46 openbsd a17537c08dc2 cb436c69 .config log report
ci-openbsd-setuid 2020/08/07 01:02 openbsd f232436aca1c cb436c69 .config log report
ci-openbsd-setuid 2020/08/06 23:37 openbsd f232436aca1c cb436c69 .config log report
ci-openbsd-setuid 2020/08/06 19:56 openbsd f232436aca1c cb436c69 .config log report
ci-openbsd-setuid 2020/08/06 12:09 openbsd 483a0179c14f 0487ea6f .config log report
ci-openbsd-setuid 2020/08/05 22:55 openbsd 5afedbbfd181 c9cef45b .config log report
ci-openbsd-setuid 2020/08/05 13:26 openbsd 455c25c8b800 02034dac .config log report
ci-openbsd-setuid 2020/08/05 00:27 openbsd fd07ab7ef78f 43f1389d .config log report
ci-openbsd-setuid 2020/08/04 21:50 openbsd fd07ab7ef78f 43f1389d .config log report
ci-openbsd-setuid 2020/08/03 11:54 openbsd 02ddb7a22afb 63a73341 .config log report
ci-openbsd-main 2020/08/03 01:34 openbsd 84e8f3e59749 63a73341 .config log report
ci-openbsd-setuid 2020/08/02 15:51 openbsd 41d03808d33a 63a73341 .config log report
ci-openbsd-setuid 2020/08/01 18:45 openbsd 724b49ef0a35 d895b3be .config log report
ci-openbsd-setuid 2020/07/31 13:19 openbsd b3881478d863 8df85ed9 .config log report
ci-openbsd-setuid 2020/07/31 10:28 openbsd b3881478d863 8df85ed9 .config log report
ci-openbsd-setuid 2020/07/31 00:11 openbsd 0a287e03b198 8df85ed9 .config log report
ci-openbsd-setuid 2020/07/30 23:02 openbsd 0a287e03b198 8df85ed9 .config log report
ci-openbsd-setuid 2020/07/30 03:24 openbsd 511c53b12928 233283a1 .config log report
ci-openbsd-setuid 2020/07/29 07:59 openbsd 511c53b12928 19a8de55 .config log report
ci-openbsd-setuid 2020/07/25 03:51 openbsd a9f43bc31f08 0a13649c .config log report
ci-openbsd-setuid 2020/07/23 12:04 openbsd fad015d206fd 340ea530 .config log report
ci-openbsd-setuid 2020/07/23 06:28 openbsd fad015d206fd 340ea530 .config log report
ci-openbsd-setuid 2020/07/22 09:44 openbsd 12d98fe19503 21f1765e .config log report
ci-openbsd-setuid 2020/07/22 01:37 openbsd 12d98fe19503 21f1765e .config log report
ci-openbsd-setuid 2020/07/21 17:26 openbsd 38194102e48c 328906f3 .config log report
ci-openbsd-setuid 2020/07/20 20:24 openbsd bea295828719 8caeeeb7 .config log report
ci-openbsd-setuid 2020/07/16 22:47 openbsd c45df27875dd 54b3c45e .config log report
ci-openbsd-setuid 2020/07/16 06:12 openbsd e44adad9b7cd ada108d0 .config log report
ci-openbsd-setuid 2020/07/16 01:51 openbsd e44adad9b7cd ada108d0 .config log report
ci-openbsd-setuid 2020/07/15 23:25 openbsd f8fbf366cc5a ada108d0 .config log report
ci-openbsd-main 2020/04/14 13:14 openbsd 25b10e5944a3 3f3c5574 .config log report