syzbot


general protection fault in fanotify_handle_event

Status: fixed on 2019/05/27 12:48
Reported-by: syzbot+15927486a4f1bfcbaf91@syzkaller.appspotmail.com
Fix commit: b1da6a51871c fsnotify: Fix NULL ptr deref in fanotify_get_fsid()
First crash: 1219d, last: 1218d

Cause bisection: introduced by (bisect log) :
commit 77115225acc67d9ac4b15f04dd138006b9cd1ef2
Author: Amir Goldstein <amir73il@gmail.com>
Date: Thu Jan 10 17:04:37 2019 +0000

  fanotify: cache fsid in fsnotify_mark_connector

Crash: general protection fault in fanotify_handle_event (log)
Repro: syz .config
Patch testing requests:
Created Duration User Patch Repo Result
2019/04/29 02:10 17m jack@suse.cz git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs.git fsnotify OK
2019/04/26 10:55 17m jack@suse.cz git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs.git fsnotify report log

Sample crash report:
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 19907 Comm: syz-executor.0 Not tainted 5.1.0-rc5+ #73
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:fanotify_get_fsid fs/notify/fanotify/fanotify.c:352 [inline]
RIP: 0010:fanotify_handle_event+0x7d0/0xc40 fs/notify/fanotify/fanotify.c:412
Code: ff ff 48 8b 18 48 8d 7b 68 48 89 f8 48 c1 e8 03 42 80 3c 38 00 0f 85 47 04 00 00 48 8b 5b 68 48 8d 7b 3c 48 89 fa 48 c1 ea 03 <42> 0f b6 0c 3a 48 89 fa 83 e2 07 83 c2 03 38 ca 7c 08 84 c9 0f 85
RSP: 0018:ffff88808e8e7b78 EFLAGS: 00010203
RAX: 1ffff11012b05edc RBX: 0000000000000000 RCX: ffffffff81c41e9e
RDX: 0000000000000007 RSI: ffffffff81c41eab RDI: 000000000000003c
RBP: ffff88808e8e7cc0 R08: ffff8880a888e700 R09: 0000000000000000
R10: ffff8880a888efd0 R11: ffff8880a888e700 R12: 0000000000000002
R13: 0000000000000000 R14: 0000000000000001 R15: dffffc0000000000
FS:  00007fe79bcae700(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f74bf328000 CR3: 000000008ad23000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 send_to_group fs/notify/fsnotify.c:243 [inline]
 fsnotify+0x725/0xbc0 fs/notify/fsnotify.c:381
 fsnotify_path include/linux/fsnotify.h:54 [inline]
 fsnotify_path include/linux/fsnotify.h:47 [inline]
 fsnotify_modify include/linux/fsnotify.h:263 [inline]
 vfs_write+0x4dc/0x580 fs/read_write.c:551
 ksys_write+0x14f/0x2d0 fs/read_write.c:599
 __do_sys_write fs/read_write.c:611 [inline]
 __se_sys_write fs/read_write.c:608 [inline]
 __x64_sys_write+0x73/0xb0 fs/read_write.c:608
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x458c29
Code: ad b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 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 7b b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fe79bcadc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000458c29
RDX: 0000000000000007 RSI: 0000000020000080 RDI: 0000000000000005
RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fe79bcae6d4
R13: 00000000004c8386 R14: 00000000004de8b8 R15: 00000000ffffffff
Modules linked in:
---[ end trace 38d84980ff49e605 ]---
RIP: 0010:fanotify_get_fsid fs/notify/fanotify/fanotify.c:352 [inline]
RIP: 0010:fanotify_handle_event+0x7d0/0xc40 fs/notify/fanotify/fanotify.c:412
Code: ff ff 48 8b 18 48 8d 7b 68 48 89 f8 48 c1 e8 03 42 80 3c 38 00 0f 85 47 04 00 00 48 8b 5b 68 48 8d 7b 3c 48 89 fa 48 c1 ea 03 <42> 0f b6 0c 3a 48 89 fa 83 e2 07 83 c2 03 38 ca 7c 08 84 c9 0f 85
RSP: 0018:ffff88808e8e7b78 EFLAGS: 00010203
RAX: 1ffff11012b05edc RBX: 0000000000000000 RCX: ffffffff81c41e9e
RDX: 0000000000000007 RSI: ffffffff81c41eab RDI: 000000000000003c
RBP: ffff88808e8e7cc0 R08: ffff8880a888e700 R09: 0000000000000000
R10: ffff8880a888efd0 R11: ffff8880a888e700 R12: 0000000000000002
R13: 0000000000000000 R14: 0000000000000001 R15: dffffc0000000000
FS:  00007fe79bcae700(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f74bf328000 CR3: 000000008ad23000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Crashes (5):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci-upstream-kasan-gce-selinux-root 2019/04/18 17:54 upstream e53f31bffe1d b0e8efcb .config log report syz
ci-upstream-kasan-gce-smack-root 2019/04/18 15:40 upstream e53f31bffe1d b0e8efcb .config log report syz
ci-upstream-kasan-gce-root 2019/04/18 13:33 upstream e53f31bffe1d b0e8efcb .config log report syz
ci-upstream-linux-next-kasan-gce-root 2019/04/18 12:53 linux-next 3f018f4a019a b0e8efcb .config log report syz
ci-upstream-linux-next-kasan-gce-root 2019/04/18 11:54 linux-next 3f018f4a019a b0e8efcb .config log report