BUG: unable to handle kernel paging request in do_con_trol

From: syzbot
Date: Mon Dec 09 2019 - 07:01:18 EST


Hello,

syzbot found the following crash on:

HEAD commit: e42617b8 Linux 5.5-rc1
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=13faf42ae00000
kernel config: https://syzkaller.appspot.com/x/.config?x=3754e2c78c1adb82
dashboard link: https://syzkaller.appspot.com/bug?extid=9bce437b96dc287eafef
compiler: gcc (GCC) 9.0.0 20181231 (experimental)

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

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+9bce437b96dc287eafef@xxxxxxxxxxxxxxxxxxxxxxxxx

BUG: unable to handle page fault for address: 000000010000000e
#PF: supervisor write access in kernel mode
#PF: error_code(0x0002) - not-present page
PGD a1d07067 P4D a1d07067 PUD 0
Oops: 0002 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 29889 Comm: syz-executor.5 Not tainted 5.5.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:memset16 arch/x86/include/asm/string_64.h:25 [inline]
RIP: 0010:scr_memsetw include/linux/vt_buffer.h:36 [inline]
RIP: 0010:csi_K drivers/tty/vt/vt.c:1558 [inline]
RIP: 0010:do_con_trol+0x47ea/0x61b0 drivers/tty/vt/vt.c:2370
Code: 08 2c 01 0f 8e b1 00 00 00 4c 8b bd 08 ff ff ff 48 63 db 44 89 e9 41 0f b7 84 24 c8 03 00 00 48 01 db d1 e9 49 01 df 4c 89 ff <f3> 66 ab 49 8d bc 24 78 04 00 00 b8 ff ff 37 00 48 89 fa 48 c1 e0
RSP: 0018:ffffc90001ce78b0 EFLAGS: 00010202
RAX: 0000000000000720 RBX: 0000000000000000 RCX: 0000000000000001
RDX: 1ffff11004ead679 RSI: ffffffff83e103ed RDI: 000000010000000e
RBP: ffffc90001ce79d0 R08: ffff8880a7f8e5c0 R09: ffff8880a7f8ee50
R10: fffffbfff14f3330 R11: ffffffff8a799987 R12: ffff88802756b000
R13: 0000000000000002 R14: 0000000000000001 R15: 000000010000000e
FS: 00007f76d2ea3700(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000010000000e CR3: 0000000098d0a000 CR4: 00000000001426e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
do_con_write.part.0+0xfd9/0x1ef0 drivers/tty/vt/vt.c:2797
do_con_write drivers/tty/vt/vt.c:2565 [inline]
con_write+0x46/0xd0 drivers/tty/vt/vt.c:3135
process_output_block drivers/tty/n_tty.c:595 [inline]
n_tty_write+0x40e/0x1080 drivers/tty/n_tty.c:2333
do_tty_write drivers/tty/tty_io.c:962 [inline]
tty_write+0x496/0x7f0 drivers/tty/tty_io.c:1046
__vfs_write+0x8a/0x110 fs/read_write.c:494
vfs_write+0x268/0x5d0 fs/read_write.c:558
ksys_write+0x14f/0x290 fs/read_write.c:611
__do_sys_write fs/read_write.c:623 [inline]
__se_sys_write fs/read_write.c:620 [inline]
__x64_sys_write+0x73/0xb0 fs/read_write.c:620
do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45a6f9
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:00007f76d2ea2c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045a6f9
RDX: 0000000000000003 RSI: 0000000020000200 RDI: 0000000000000003
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f76d2ea36d4
R13: 00000000004cbbaf R14: 00000000004e5858 R15: 00000000ffffffff
Modules linked in:
CR2: 000000010000000e
---[ end trace 2efe1884df5826e9 ]---
RIP: 0010:memset16 arch/x86/include/asm/string_64.h:25 [inline]
RIP: 0010:scr_memsetw include/linux/vt_buffer.h:36 [inline]
RIP: 0010:csi_K drivers/tty/vt/vt.c:1558 [inline]
RIP: 0010:do_con_trol+0x47ea/0x61b0 drivers/tty/vt/vt.c:2370
Code: 08 2c 01 0f 8e b1 00 00 00 4c 8b bd 08 ff ff ff 48 63 db 44 89 e9 41 0f b7 84 24 c8 03 00 00 48 01 db d1 e9 49 01 df 4c 89 ff <f3> 66 ab 49 8d bc 24 78 04 00 00 b8 ff ff 37 00 48 89 fa 48 c1 e0
RSP: 0018:ffffc90001ce78b0 EFLAGS: 00010202
RAX: 0000000000000720 RBX: 0000000000000000 RCX: 0000000000000001
RDX: 1ffff11004ead679 RSI: ffffffff83e103ed RDI: 000000010000000e
RBP: ffffc90001ce79d0 R08: ffff8880a7f8e5c0 R09: ffff8880a7f8ee50
R10: fffffbfff14f3330 R11: ffffffff8a799987 R12: ffff88802756b000
R13: 0000000000000002 R14: 0000000000000001 R15: 000000010000000e
FS: 00007f76d2ea3700(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000001eaad40 CR3: 0000000098d0a000 CR4: 00000000001426f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


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