BUG: unable to handle kernel paging request in h4_recv_buf

From: syzbot
Date: Wed Jan 02 2019 - 04:01:13 EST


Hello,

syzbot found the following crash on:

HEAD commit: 28e8c4bc8eb4 Merge tag 'rtc-4.21' of git://git.kernel.org/..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=14a063fd400000
kernel config: https://syzkaller.appspot.com/x/.config?x=c2ab9708c613a224
dashboard link: https://syzkaller.appspot.com/bug?extid=017a32f149406df32703
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13d654d7400000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=174483fd400000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+017a32f149406df32703@xxxxxxxxxxxxxxxxxxxxxxxxx

Bluetooth: hci0: sending frame failed (-49)
Bluetooth: hci0: command 0x1001 tx timeout
Bluetooth: hci0: sending frame failed (-49)
Bluetooth: hci0: command 0x1009 tx timeout
Bluetooth: hci0: Frame reassembly failed (-84)
BUG: unable to handle kernel paging request at ffffffffffffffd6
#PF error: [normal kernel read fault]
PGD 9871067 P4D 9871067 PUD 9873067 PMD 0
Oops: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 7 Comm: kworker/u4:0 Not tainted 4.20.0+ #4
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events_unbound flush_to_ldisc
RIP: 0010:h4_recv_buf+0x1ea/0xda0 drivers/bluetooth/hci_h4.c:211
Code: b6 14 10 48 89 c8 83 e0 07 83 c0 01 38 d0 7c 08 84 d2 0f 85 d7 0a 00 00 48 ba 00 00 00 00 00 fc ff df 48 8b 45 d0 4c 8d 60 70 <0f> b7 58 2a 4c 89 e0 48 c1 e8 03 0f b6 04 10 84 c0 74 08 3c 03 0f
RSP: 0018:ffff8880a945f6c0 EFLAGS: 00010246
RAX: ffffffffffffffac RBX: 0000000000000000 RCX: ffffffffffffffd6
RDX: dffffc0000000000 RSI: ffffffff85883972 RDI: 0000000000000005
RBP: ffff8880a945f748 R08: ffff8880a944e1c0 R09: 0000000000000003
R10: ffffed1015ce5b8f R11: ffff8880ae72dc7b R12: 000000000000001c
R13: ffff88808c9fea40 R14: ffff8880829e76e0 R15: 0000000000000006
FS: 0000000000000000(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 0000000098164000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
h4_recv+0xe4/0x200 drivers/bluetooth/hci_h4.c:131
hci_uart_tty_receive+0x22b/0x530 drivers/bluetooth/hci_ldisc.c:607
tty_ldisc_receive_buf+0x164/0x1c0 drivers/tty/tty_buffer.c:465
tty_port_default_receive_buf+0x114/0x190 drivers/tty/tty_port.c:38
receive_buf drivers/tty/tty_buffer.c:481 [inline]
flush_to_ldisc+0x3b2/0x590 drivers/tty/tty_buffer.c:533
process_one_work+0xd0c/0x1ce0 kernel/workqueue.c:2153
worker_thread+0x143/0x14a0 kernel/workqueue.c:2296
kthread+0x357/0x430 kernel/kthread.c:246
ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352
Modules linked in:
CR2: ffffffffffffffd6
---[ end trace 6acbbb9f58ccf0f7 ]---
RIP: 0010:h4_recv_buf+0x1ea/0xda0 drivers/bluetooth/hci_h4.c:211
Code: b6 14 10 48 89 c8 83 e0 07 83 c0 01 38 d0 7c 08 84 d2 0f 85 d7 0a 00 00 48 ba 00 00 00 00 00 fc ff df 48 8b 45 d0 4c 8d 60 70 <0f> b7 58 2a 4c 89 e0 48 c1 e8 03 0f b6 04 10 84 c0 74 08 3c 03 0f
RSP: 0018:ffff8880a945f6c0 EFLAGS: 00010246
RAX: ffffffffffffffac RBX: 0000000000000000 RCX: ffffffffffffffd6
RDX: dffffc0000000000 RSI: ffffffff85883972 RDI: 0000000000000005
RBP: ffff8880a945f748 R08: ffff8880a944e1c0 R09: 0000000000000003
R10: ffffed1015ce5b8f R11: ffff8880ae72dc7b R12: 000000000000001c
R13: ffff88808c9fea40 R14: ffff8880829e76e0 R15: 0000000000000006
FS: 0000000000000000(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 0000000098164000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


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