BUG: unable to handle kernel paging request in vga16fb_imageblit (3)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 455e73a07f6e Merge tag 'clk-for-linus' of git://git.kernel..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1749add7b00000
kernel config: https://syzkaller.appspot.com/x/.config?x=10dbcfb2ca32737b
dashboard link: https://syzkaller.appspot.com/bug?extid=0569333f742be476ff6e
compiler: Debian clang version 11.0.1-2, GNU ld (GNU Binutils for Debian) 2.35.2
CC: [ak...@linux-foundation.org dri-...@lists.freedesktop.org ge...@linux-m68k.org linux...@vger.kernel.org linux-...@vger.kernel.org masa...@kernel.org oj...@kernel.org]

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+056933...@syzkaller.appspotmail.com

BUG: unable to handle page fault for address: ffff8880c00a00f3
#PF: supervisor write access in kernel mode
#PF: error_code(0x0002) - not-present page
PGD 11201067 P4D 11201067 PUD 0
Oops: 0002 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 5341 Comm: syz-executor.1 Not tainted 5.16.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:writeb arch/x86/include/asm/io.h:66 [inline]
RIP: 0010:vga_imageblit_expand drivers/video/fbdev/vga16fb.c:1168 [inline]
RIP: 0010:vga16fb_imageblit+0xf02/0x2650 drivers/video/fbdev/vga16fb.c:1260
Code: 0f 84 a4 16 00 00 e8 1d 74 d0 fc 66 90 48 8b 04 24 48 8d 58 14 48 89 d8 48 c1 e8 03 42 8a 04 28 84 c0 0f 85 4d 14 00 00 8a 03 <41> 88 06 0f ae e8 41 8a 06 b0 05 ba ce 03 00 00 ee 48 c7 c0 98 fc
RSP: 0018:ffffc9000429f400 EFLAGS: 00010246
RAX: 1ffff92000853e00 RBX: ffffc9000429f634 RCX: 1ffffffff1931f93
RDX: 00000000000003cf RSI: 0000000000000001 RDI: 0000000000000000
RBP: 0000000000000007 R08: ffffffff8469b878 R09: ffffc9000429f620
R10: fffff52000853ece R11: 0000000000000000 R12: ffff888140dfd210
R13: dffffc0000000000 R14: ffff8880c00a00f3 R15: 00000000c00000e0
FS: 00007f2e5fbd8700(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffff8880c00a00f3 CR3: 000000001a049000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
bit_putcs+0x18f8/0x1df0
fbcon_putcs+0x2c0/0x440 drivers/video/fbdev/core/fbcon.c:1277
do_update_region+0x4f6/0x710 drivers/tty/vt/vt.c:676
invert_screen+0xc03/0xe40 drivers/tty/vt/vt.c:800
highlight drivers/tty/vt/selection.c:57 [inline]
clear_selection+0x55/0x70 drivers/tty/vt/selection.c:84
vc_do_resize+0x79b/0x1930 drivers/tty/vt/vt.c:1257
fbcon_modechanged+0x7b6/0x1240 drivers/video/fbdev/core/fbcon.c:2171
do_fb_ioctl+0x7f2/0x900 drivers/video/fbdev/core/fbmem.c:1114
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:874 [inline]
__se_sys_ioctl+0xfb/0x170 fs/ioctl.c:860
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f2e61262eb9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f2e5fbd8168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f2e61375f60 RCX: 00007f2e61262eb9
RDX: 0000000020000200 RSI: 0000000000004601 RDI: 0000000000000003
RBP: 00007f2e612bd08d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe1511289f R14: 00007f2e5fbd8300 R15: 0000000000022000
</TASK>
Modules linked in:
CR2: ffff8880c00a00f3
---[ end trace 2856e85110900cd1 ]---
RIP: 0010:writeb arch/x86/include/asm/io.h:66 [inline]
RIP: 0010:vga_imageblit_expand drivers/video/fbdev/vga16fb.c:1168 [inline]
RIP: 0010:vga16fb_imageblit+0xf02/0x2650 drivers/video/fbdev/vga16fb.c:1260
Code: 0f 84 a4 16 00 00 e8 1d 74 d0 fc 66 90 48 8b 04 24 48 8d 58 14 48 89 d8 48 c1 e8 03 42 8a 04 28 84 c0 0f 85 4d 14 00 00 8a 03 <41> 88 06 0f ae e8 41 8a 06 b0 05 ba ce 03 00 00 ee 48 c7 c0 98 fc
RSP: 0018:ffffc9000429f400 EFLAGS: 00010246
RAX: 1ffff92000853e00 RBX: ffffc9000429f634 RCX: 1ffffffff1931f93
RDX: 00000000000003cf RSI: 0000000000000001 RDI: 0000000000000000
RBP: 0000000000000007 R08: ffffffff8469b878 R09: ffffc9000429f620
R10: fffff52000853ece R11: 0000000000000000 R12: ffff888140dfd210
R13: dffffc0000000000 R14: ffff8880c00a00f3 R15: 00000000c00000e0
FS: 00007f2e5fbd8700(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffff8880c00a00f3 CR3: 000000001a049000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
0: 0f 84 a4 16 00 00 je 0x16aa
6: e8 1d 74 d0 fc callq 0xfcd07428
b: 66 90 xchg %ax,%ax
d: 48 8b 04 24 mov (%rsp),%rax
11: 48 8d 58 14 lea 0x14(%rax),%rbx
15: 48 89 d8 mov %rbx,%rax
18: 48 c1 e8 03 shr $0x3,%rax
1c: 42 8a 04 28 mov (%rax,%r13,1),%al
20: 84 c0 test %al,%al
22: 0f 85 4d 14 00 00 jne 0x1475
28: 8a 03 mov (%rbx),%al
* 2a: 41 88 06 mov %al,(%r14) <-- trapping instruction
2d: 0f ae e8 lfence
30: 41 8a 06 mov (%r14),%al
33: b0 05 mov $0x5,%al
35: ba ce 03 00 00 mov $0x3ce,%edx
3a: ee out %al,(%dx)
3b: 48 rex.W
3c: c7 .byte 0xc7
3d: c0 .byte 0xc0
3e: 98 cwtl
3f: fc cld


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.