syzbot


WARNING in userfaultfd_ioctl

Status: fixed on 2018/12/28 00:02
Subsystems: fs
[Documentation on labels]
Reported-by: syzbot+06c7092e7d71218a2c16@syzkaller.appspotmail.com
Fix commit: 01e881f5a1fc userfaultfd: check VM_MAYWRITE was set after verifying the uffd is registered
First crash: 2029d, last: 2017d
Discussions (4)
Title Replies (including bot) Last reply
[PATCH 4.14 00/72] 4.14.90-stable review 86 (86) 2018/12/21 12:59
[PATCH 4.19 00/44] 4.19.11-stable review 53 (53) 2018/12/19 18:37
[PATCH 0/1] userfaultfd: check VM_MAYWRITE was set after verifying the uffd is registered 5 (5) 2018/12/07 03:43
WARNING in userfaultfd_ioctl 0 (1) 2018/12/03 23:10

Sample crash report:
IPVS: ftp: loaded support on port[0] = 21
WARNING: CPU: 1 PID: 6028 at fs/userfaultfd.c:1569 userfaultfd_unregister fs/userfaultfd.c:1569 [inline]
WARNING: CPU: 1 PID: 6028 at fs/userfaultfd.c:1569 userfaultfd_ioctl+0x3d30/0x5610 fs/userfaultfd.c:1845
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 6028 Comm: syz-executor210 Not tainted 4.20.0-rc4+ #358
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x244/0x39d lib/dump_stack.c:113
 panic+0x2ad/0x55c kernel/panic.c:188
 __warn.cold.8+0x20/0x45 kernel/panic.c:540
 report_bug+0x254/0x2d0 lib/bug.c:186
 fixup_bug arch/x86/kernel/traps.c:178 [inline]
 do_error_trap+0x11b/0x200 arch/x86/kernel/traps.c:271
 do_invalid_op+0x36/0x40 arch/x86/kernel/traps.c:290
 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:969
RIP: 0010:userfaultfd_unregister fs/userfaultfd.c:1569 [inline]
RIP: 0010:userfaultfd_ioctl+0x3d30/0x5610 fs/userfaultfd.c:1845
Code: 85 c0 f6 ff ff 48 c1 e8 03 42 80 3c 30 00 0f 84 a3 fa ff ff 48 8b bd c0 f6 ff ff e8 4a 60 db ff e9 92 fa ff ff e8 20 07 98 ff <0f> 0b e9 cd f7 ff ff e8 14 07 98 ff 48 8b 95 f0 f6 ff ff b9 01 00
RSP: 0018:ffff8881b8f37270 EFLAGS: 00010293
RAX: ffff8881c298a080 RBX: 00000000080000d0 RCX: ffffffff81e77b7b
RDX: 0000000000000000 RSI: ffffffff81e783b0 RDI: 0000000000000007
RBP: ffff8881b8f37c00 R08: ffff8881c298a080 R09: 0000000000000008
R10: 0000000000003cb4 R11: ffff8881c298a080 R12: 0000000020011000
R13: 0000000000000000 R14: dffffc0000000000 R15: ffff8881c2919948
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:509 [inline]
 do_vfs_ioctl+0x1de/0x1790 fs/ioctl.c:696
 ksys_ioctl+0xa9/0xd0 fs/ioctl.c:713
 __do_sys_ioctl fs/ioctl.c:720 [inline]
 __se_sys_ioctl fs/ioctl.c:718 [inline]
 __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x440ad9
Code: 23 02 00 85 c0 b8 00 00 00 00 48 0f 44 c3 5b c3 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 0b 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00000000007dff68 EFLAGS: 00000217 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007ffe13628d50 RCX: 0000000000440ad9
RDX: 0000000020d62fe0 RSI: 000000008010aa01 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000004 R11: 0000000000000217 R12: 0000000000402270
R13: 0000000000402300 R14: 0000000000000000 R15: 0000000000000000
Kernel Offset: disabled
Rebooting in 86400 seconds..

Crashes (11):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/12/01 21:15 upstream d8f190ee836a 5a581673 .config console log report syz C ci-upstream-kasan-gce
2018/12/01 19:37 upstream d8f190ee836a 5a581673 .config console log report syz C ci-upstream-kasan-gce
2018/12/01 21:53 upstream d8f190ee836a 5a581673 .config console log report syz C ci-upstream-kasan-gce-386
2018/12/01 20:49 upstream d8f190ee836a 5a581673 .config console log report syz C ci-upstream-kasan-gce-386
2018/12/13 13:02 upstream f5d582777bcb f3d9d594 .config console log report ci-upstream-kasan-gce
2018/12/13 08:17 upstream f5d582777bcb 02613a41 .config console log report ci-upstream-kasan-gce-root
2018/12/05 01:45 upstream 0072a0c14d5b f162ad97 .config console log report ci-upstream-kasan-gce-root
2018/12/03 05:42 upstream 6a512726090a 7dcaeaf3 .config console log report ci-upstream-kasan-gce
2018/12/01 18:34 upstream d8f190ee836a 5a581673 .config console log report ci-upstream-kasan-gce
2018/12/09 10:58 upstream 8214bdf7d3e6 c7918378 .config console log report ci-upstream-kasan-gce-386
2018/12/01 18:35 upstream d8f190ee836a 5a581673 .config console log report ci-upstream-kasan-gce-386
* Struck through repros no longer work on HEAD.