BUG: unable to handle kernel paging request in vga16fb_imageblit (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: f5d8eef0 Linux 4.19.154
git tree: linux-4.19.y
console output: https://syzkaller.appspot.com/x/log.txt?x=15005cb8500000
kernel config: https://syzkaller.appspot.com/x/.config?x=be9b9357b4680aa1
dashboard link: https://syzkaller.appspot.com/bug?extid=b6895240ddf11bc2942d
compiler: gcc (GCC) 10.1.0-syz 20200507

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+b68952...@syzkaller.appspotmail.com

BUG: unable to handle kernel paging request at ffff888001000095
PGD de01067 P4D de01067 PUD de02067 PMD 80000000010001e1
Oops: 0003 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 2425 Comm: syz-executor.2 Not tainted 4.19.154-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:65 [inline]
RIP: 0010:vga_imageblit_expand drivers/video/fbdev/vga16fb.c:1176 [inline]
RIP: 0010:vga16fb_imageblit+0xc2f/0x2260 drivers/video/fbdev/vga16fb.c:1260
Code: 48 83 c5 01 48 89 f8 48 89 f9 48 83 c3 01 48 c1 e8 03 83 e1 07 42 0f b6 04 38 38 c8 7f 08 84 c0 0f 85 86 0f 00 00 0f b6 45 ff <88> 02 44 89 e6 31 ff 29 de e8 63 d4 bc fd 4c 39 eb 75 b8 48 8b 7c
RSP: 0018:ffff88805643f3d0 EFLAGS: 00010246
RAX: 0000000000000030 RBX: ffff888001000096 RCX: 0000000000000001
RDX: ffff888001000095 RSI: ffffffff83a7fbcf RDI: ffff8882393d85d1
RBP: ffff8882393d85d2 R08: ffff8882393d85df R09: 0000000000000000
R10: 0000000000000005 R11: 0000000000000000 R12: 0000000001000096
R13: ffff888001000096 R14: ffff888001000095 R15: dffffc0000000000
FS: 00007fa61223b700(0000) GS:ffff8880ba100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffff888001000095 CR3: 00000000979fc000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
soft_cursor+0x514/0xa30 drivers/video/fbdev/core/softcursor.c:74
bit_cursor+0x1126/0x1740 drivers/video/fbdev/core/bitblit.c:377
fbcon_cursor+0x523/0x700 drivers/video/fbdev/core/fbcon.c:1309
fbcon_scroll+0x2fc/0x3440 drivers/video/fbdev/core/fbcon.c:1666
con_scroll+0x5f8/0x720 drivers/tty/vt/vt.c:637
lf+0x262/0x2b0 drivers/tty/vt/vt.c:1491
do_con_trol+0x1df/0x5970 drivers/tty/vt/vt.c:2159
do_con_write+0xbea/0x1d90 drivers/tty/vt/vt.c:2810
con_write+0x22/0xb0 drivers/tty/vt/vt.c:3145
process_output_block drivers/tty/n_tty.c:593 [inline]
n_tty_write+0x3c0/0xff0 drivers/tty/n_tty.c:2331
do_tty_write drivers/tty/tty_io.c:960 [inline]
tty_write+0x496/0x810 drivers/tty/tty_io.c:1044
__vfs_write+0xf7/0x770 fs/read_write.c:485
vfs_write+0x1f3/0x540 fs/read_write.c:549
ksys_write+0x12b/0x2a0 fs/read_write.c:599
do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45deb9
Code: 0d b4 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 db b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fa61223ac78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 000000000003a680 RCX: 000000000045deb9
RDX: 0000000000001006 RSI: 0000000020001440 RDI: 0000000000000004
RBP: 000000000118bf60 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118bf2c
R13: 00007fffefdb025f R14: 00007fa61223b9c0 R15: 000000000118bf2c
Modules linked in:
CR2: ffff888001000095
BUG: unable to handle kernel paging request at ffff888001000095
PGD de01067 P4D de01067 PUD de02067 PMD 80000000010001e1
Oops: 0003 [#2] PREEMPT SMP KASAN
CPU: 1 PID: 2425 Comm: syz-executor.2 Not tainted 4.19.154-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:65 [inline]
RIP: 0010:vga_imageblit_expand drivers/video/fbdev/vga16fb.c:1176 [inline]
RIP: 0010:vga16fb_imageblit+0xc2f/0x2260 drivers/video/fbdev/vga16fb.c:1260
Code: 48 83 c5 01 48 89 f8 48 89 f9 48 83 c3 01 48 c1 e8 03 83 e1 07 42 0f b6 04 38 38 c8 7f 08 84 c0 0f 85 86 0f 00 00 0f b6 45 ff <88> 02 44 89 e6 31 ff 29 de e8 63 d4 bc fd 4c 39 eb 75 b8 48 8b 7c
RSP: 0018:ffff88805643ec08 EFLAGS: 00010046
RAX: 0000000000000030 RBX: ffff888001000096 RCX: 0000000000000001
RDX: ffff888001000095 RSI: ffffffff83a7fbcf RDI: ffff8882393d85e1
RBP: ffff8882393d85e2 R08: ffff8882393d85ef R09: 0000000000000000
R10: 0000000000000005 R11: ffffffff8c65c05b R12: 0000000001000096
R13: ffff888001000096 R14: ffff888001000095 R15: dffffc0000000000
FS: 00007fa61223b700(0000) GS:ffff8880ba100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffff888001000095 CR3: 00000000979fc000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
soft_cursor+0x514/0xa30 drivers/video/fbdev/core/softcursor.c:74
bit_cursor+0x1126/0x1740 drivers/video/fbdev/core/bitblit.c:377
fbcon_cursor+0x523/0x700 drivers/video/fbdev/core/fbcon.c:1309
fbcon_blank+0x8b5/0xec0 drivers/video/fbdev/core/fbcon.c:2214
do_unblank_screen+0x241/0x610 drivers/tty/vt/vt.c:4276
bust_spinlocks+0x5b/0xe0
oops_end+0x2b/0xe0 arch/x86/kernel/dumpstack.c:336
no_context+0x75a/0x940 arch/x86/mm/fault.c:830
__bad_area_nosemaphore+0x2de/0x400 arch/x86/mm/fault.c:918
__do_page_fault+0x17b/0xd60 arch/x86/mm/fault.c:1344
page_fault+0x1e/0x30 arch/x86/entry/entry_64.S:1205
RIP: 0010:writeb arch/x86/include/asm/io.h:65 [inline]
RIP: 0010:vga_imageblit_expand drivers/video/fbdev/vga16fb.c:1176 [inline]
RIP: 0010:vga16fb_imageblit+0xc2f/0x2260 drivers/video/fbdev/vga16fb.c:1260
Code: 48 83 c5 01 48 89 f8 48 89 f9 48 83 c3 01 48 c1 e8 03 83 e1 07 42 0f b6 04 38 38 c8 7f 08 84 c0 0f 85 86 0f 00 00 0f b6 45 ff <88> 02 44 89 e6 31 ff 29 de e8 63 d4 bc fd 4c 39 eb 75 b8 48 8b 7c
RSP: 0018:ffff88805643f3d0 EFLAGS: 00010246
RAX: 0000000000000030 RBX: ffff888001000096 RCX: 0000000000000001
RDX: ffff888001000095 RSI: ffffffff83a7fbcf RDI: ffff8882393d85d1
RBP: ffff8882393d85d2 R08: ffff8882393d85df R09: 0000000000000000
R10: 0000000000000005 R11: 0000000000000000 R12: 0000000001000096
R13: ffff888001000096 R14: ffff888001000095 R15: dffffc0000000000
soft_cursor+0x514/0xa30 drivers/video/fbdev/core/softcursor.c:74
bit_cursor+0x1126/0x1740 drivers/video/fbdev/core/bitblit.c:377
fbcon_cursor+0x523/0x700 drivers/video/fbdev/core/fbcon.c:1309
fbcon_scroll+0x2fc/0x3440 drivers/video/fbdev/core/fbcon.c:1666
con_scroll+0x5f8/0x720 drivers/tty/vt/vt.c:637
lf+0x262/0x2b0 drivers/tty/vt/vt.c:1491
do_con_trol+0x1df/0x5970 drivers/tty/vt/vt.c:2159
do_con_write+0xbea/0x1d90 drivers/tty/vt/vt.c:2810
con_write+0x22/0xb0 drivers/tty/vt/vt.c:3145
process_output_block drivers/tty/n_tty.c:593 [inline]
n_tty_write+0x3c0/0xff0 drivers/tty/n_tty.c:2331
do_tty_write drivers/tty/tty_io.c:960 [inline]
tty_write+0x496/0x810 drivers/tty/tty_io.c:1044
__vfs_write+0xf7/0x770 fs/read_write.c:485
vfs_write+0x1f3/0x540 fs/read_write.c:549
ksys_write+0x12b/0x2a0 fs/read_write.c:599
do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45deb9
Code: 0d b4 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 db b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fa61223ac78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 000000000003a680 RCX: 000000000045deb9
RDX: 0000000000001006 RSI: 0000000020001440 RDI: 0000000000000004
RBP: 000000000118bf60 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118bf2c
R13: 00007fffefdb025f R14: 00007fa61223b9c0 R15: 000000000118bf2c
Modules linked in:
CR2: ffff888001000095
---[ end trace 6a637e12d685489a ]---
RIP: 0010:writeb arch/x86/include/asm/io.h:65 [inline]
RIP: 0010:vga_imageblit_expand drivers/video/fbdev/vga16fb.c:1176 [inline]
RIP: 0010:vga16fb_imageblit+0xc2f/0x2260 drivers/video/fbdev/vga16fb.c:1260
Code: 48 83 c5 01 48 89 f8 48 89 f9 48 83 c3 01 48 c1 e8 03 83 e1 07 42 0f b6 04 38 38 c8 7f 08 84 c0 0f 85 86 0f 00 00 0f b6 45 ff <88> 02 44 89 e6 31 ff 29 de e8 63 d4 bc fd 4c 39 eb 75 b8 48 8b 7c
RSP: 0018:ffff88805643f3d0 EFLAGS: 00010246
RAX: 0000000000000030 RBX: ffff888001000096 RCX: 0000000000000001
RDX: ffff888001000095 RSI: ffffffff83a7fbcf RDI: ffff8882393d85d1
RBP: ffff8882393d85d2 R08: ffff8882393d85df R09: 0000000000000000
R10: 0000000000000005 R11: 0000000000000000 R12: 0000000001000096
R13: ffff888001000096 R14: ffff888001000095 R15: dffffc0000000000
FS: 00007fa61223b700(0000) GS:ffff8880ba100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffff888001000095 CR3: 00000000979fc000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


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[syzbot]

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