syzbot


general protection fault in fbcon_modechanged

Status: auto-closed as invalid on 2020/04/09 05:43
Subsystems: fbdev
[Documentation on labels]
Reported-by: syzbot+d396a0ae28ab4507bc89@syzkaller.appspotmail.com
First crash: 1592d, last: 1590d
Discussions (1)
Title Replies (including bot) Last reply
general protection fault in fbcon_modechanged 0 (1) 2019/12/10 04:26

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: 0 PID: 26035 Comm: syz-executor.1 Not tainted 5.5.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:fbcon_modechanged+0xeb/0x790 drivers/video/fbdev/core/fbcon.c:2967
Code: 8d 14 ff 4c 8b 2c d5 80 19 10 8c 48 ba 00 00 00 00 00 fc ff df 49 8d 85 7c 03 00 00 48 89 c1 48 89 45 c8 83 e0 07 48 c1 e9 03 <0f> b6 14 11 38 c2 7f 08 84 d2 0f 85 61 05 00 00 41 0f b6 b5 7c 03
RSP: 0018:ffffc90001647778 EFLAGS: 00010207
RAX: 0000000000000004 RBX: ffff888218ef2800 RCX: 000000000000006f
RDX: dffffc0000000000 RSI: ffffffff83b22859 RDI: ffffffff8c102af0
RBP: ffffc900016477c8 R08: ffff88805ceda580 R09: ffffed1015d0703d
R10: ffffed1015d0703c R11: ffff8880ae8381e3 R12: ffff8880a3fcb000
R13: 0000000000000000 R14: ffff8880a3fcb468 R15: 000000000000003e
FS:  00007f3d21c82700(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2d221000 CR3: 000000009a3ec000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 fbcon_update_vcs+0x42/0x50 drivers/video/fbdev/core/fbcon.c:3038
 fb_set_var+0xb32/0xdd0 drivers/video/fbdev/core/fbmem.c:1051
 do_fb_ioctl+0x390/0x7d0 drivers/video/fbdev/core/fbmem.c:1104
 fb_ioctl+0xe6/0x130 drivers/video/fbdev/core/fbmem.c:1180
 vfs_ioctl fs/ioctl.c:47 [inline]
 file_ioctl fs/ioctl.c:545 [inline]
 do_vfs_ioctl+0x977/0x14e0 fs/ioctl.c:732
 ksys_ioctl+0xab/0xd0 fs/ioctl.c:749
 __do_sys_ioctl fs/ioctl.c:756 [inline]
 __se_sys_ioctl fs/ioctl.c:754 [inline]
 __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:754
 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45a849
Code: ad b6 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 b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f3d21c81c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045a849
RDX: 0000000020000000 RSI: 0000000000004601 RDI: 0000000000000004
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f3d21c826d4
R13: 00000000004c3057 R14: 00000000004d8358 R15: 00000000ffffffff
Modules linked in:
---[ end trace dbb6cab209a6d9f9 ]---
RIP: 0010:fbcon_modechanged+0xeb/0x790 drivers/video/fbdev/core/fbcon.c:2967
Code: 8d 14 ff 4c 8b 2c d5 80 19 10 8c 48 ba 00 00 00 00 00 fc ff df 49 8d 85 7c 03 00 00 48 89 c1 48 89 45 c8 83 e0 07 48 c1 e9 03 <0f> b6 14 11 38 c2 7f 08 84 d2 0f 85 61 05 00 00 41 0f b6 b5 7c 03
RSP: 0018:ffffc90001647778 EFLAGS: 00010207
RAX: 0000000000000004 RBX: ffff888218ef2800 RCX: 000000000000006f
RDX: dffffc0000000000 RSI: ffffffff83b22859 RDI: ffffffff8c102af0
RBP: ffffc900016477c8 R08: ffff88805ceda580 R09: ffffed1015d0703d
R10: ffffed1015d0703c R11: ffff8880ae8381e3 R12: ffff8880a3fcb000
R13: 0000000000000000 R14: ffff8880a3fcb468 R15: 000000000000003e
FS:  00007f3d21c82700(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffe339eba30 CR3: 000000009a3ec000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/12/11 05:42 upstream 6794862a16ef 101194eb .config console log report ci-upstream-kasan-gce-selinux-root
2019/12/10 14:59 upstream 6794862a16ef 5a5826a1 .config console log report ci-upstream-kasan-gce
2019/12/09 13:58 upstream e42617b825f8 b31eda3d .config console log report ci-upstream-kasan-gce-386
* Struck through repros no longer work on HEAD.