BUG: sleeping function called from invalid context in __do_page_fault

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 07c4b9e9 Merge tag 'scsi-fixes' of git://git.kernel.org/pu..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1225508ee00000
kernel config: https://syzkaller.appspot.com/x/.config?x=79f79de2a27d3e3d
dashboard link: https://syzkaller.appspot.com/bug?extid=9d337da2f26f10358060
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+9d337d...@syzkaller.appspotmail.com

BUG: sleeping function called from invalid context at
arch/x86/mm/fault.c:1399
in_atomic(): 0, irqs_disabled(): 1, non_block: 0, pid: 9240, name:
syz-executor.3
1 lock held by syz-executor.3/9240:
#0: ffff8880927eb918 (&mm->mmap_sem#2){++++}, at: do_user_addr_fault
arch/x86/mm/fault.c:1382 [inline]
#0: ffff8880927eb918 (&mm->mmap_sem#2){++++}, at:
__do_page_fault+0x33c/0xd80 arch/x86/mm/fault.c:1506
irq event stamp: 741026
hardirqs last enabled at (741025): [<ffffffff81a342d0>] count_memcg_events
include/linux/memcontrol.h:750 [inline]
hardirqs last enabled at (741025): [<ffffffff81a342d0>]
count_memcg_event_mm include/linux/memcontrol.h:771 [inline]
hardirqs last enabled at (741025): [<ffffffff81a342d0>]
handle_mm_fault+0x7a0/0xa50 mm/memory.c:4092
hardirqs last disabled at (741026): [<ffffffff8100675f>]
trace_hardirqs_off_thunk+0x1a/0x1c arch/x86/entry/thunk_64.S:42
softirqs last enabled at (737900): [<ffffffff880006cd>]
__do_softirq+0x6cd/0x98c kernel/softirq.c:319
softirqs last disabled at (737885): [<ffffffff81478ceb>] invoke_softirq
kernel/softirq.c:373 [inline]
softirqs last disabled at (737885): [<ffffffff81478ceb>]
irq_exit+0x19b/0x1e0 kernel/softirq.c:413
CPU: 0 PID: 9240 Comm: syz-executor.3 Not tainted 5.5.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x197/0x210 lib/dump_stack.c:118
___might_sleep.cold+0x1fb/0x23e kernel/sched/core.c:6800
__might_sleep+0x95/0x190 kernel/sched/core.c:6753
do_user_addr_fault arch/x86/mm/fault.c:1399 [inline]
__do_page_fault+0x369/0xd80 arch/x86/mm/fault.c:1506
do_page_fault+0x38/0x590 arch/x86/mm/fault.c:1530
page_fault+0x39/0x40 arch/x86/entry/entry_64.S:1203
RIP: 0010:prepare_exit_to_usermode+0x157/0x3a0 arch/x86/entry/common.c:189
Code: 00 00 00 fc ff df 65 4c 8b 2c 25 c0 1e 02 00 49 8d bd 94 08 00 00 48
89 fa 48 c1 ea 03 0f b6 14 02 48 89 f8 83 e0 07 83 c0 03 <38> 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
RSP: 0000:ffffc90001ea7f28 EFLAGS: 00010002
RAX: 0000000000000007 RBX: ffff88805d892000 RCX: ffffffff81009b3f
RDX: 0000000000000000 RSI: ffffffff81009b49 RDI: ffff88805d892894
RBP: ffffc90001ea7f48 R08: ffff88805d892000 R09: ffffed100bb12401
R10: ffffed100bb12400 R11: ffff88805d892007 R12: ffffc90001ea7f58
R13: ffff88805d892000 R14: 0000000000000000 R15: 0000000000000000
ret_from_intr+0x26/0x36
RIP: 0033:0x4036e2
Code: 55 41 54 49 89 fc 55 53 48 81 ec b8 10 00 00 64 48 8b 04 25 28 00 00
00 48 89 84 24 a8 10 00 00 31 c0 be 02 00 00 00 4c 89 e7 <e8> 49 9c 05 00
85 c0 0f 84 00 03 00 00 4c 89 e7 e8 69 51 05 00 48
RSP: 002b:0000000000a6ecc0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 000000000004a9df RCX: 00000000004143c0
RDX: 000000000000000c RSI: 0000000000000002 RDI: 0000000000a6fdf0
RBP: 00000000000000c2 R08: 0000000000000001 R09: 0000000001d5f940
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000a6fdf0
R13: 0000000000a6fde0 R14: 0000000000000000 R15: 0000000000a6fdf0
BUG: kernel NULL pointer dereference, address: 0000000000000007
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 5d84a067 P4D 5d84a067 PUD 5d84b067 PMD 0
Oops: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 9240 Comm: syz-executor.3 Tainted: G W
5.5.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
RIP: 0010:prepare_exit_to_usermode+0x157/0x3a0 arch/x86/entry/common.c:189
Code: 00 00 00 fc ff df 65 4c 8b 2c 25 c0 1e 02 00 49 8d bd 94 08 00 00 48
89 fa 48 c1 ea 03 0f b6 14 02 48 89 f8 83 e0 07 83 c0 03 <38> 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
RSP: 0000:ffffc90001ea7f28 EFLAGS: 00010002
RAX: 0000000000000007 RBX: ffff88805d892000 RCX: ffffffff81009b3f
RDX: 0000000000000000 RSI: ffffffff81009b49 RDI: ffff88805d892894
RBP: ffffc90001ea7f48 R08: ffff88805d892000 R09: ffffed100bb12401
R10: ffffed100bb12400 R11: ffff88805d892007 R12: ffffc90001ea7f58
R13: ffff88805d892000 R14: 0000000000000000 R15: 0000000000000000
FS: 0000000001d5f940(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000007 CR3: 000000005d849000 CR4: 00000000001426f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
ret_from_intr+0x26/0x36
RIP: 0033:0x4036e2
Code: 55 41 54 49 89 fc 55 53 48 81 ec b8 10 00 00 64 48 8b 04 25 28 00 00
00 48 89 84 24 a8 10 00 00 31 c0 be 02 00 00 00 4c 89 e7 <e8> 49 9c 05 00
85 c0 0f 84 00 03 00 00 4c 89 e7 e8 69 51 05 00 48
RSP: 002b:0000000000a6ecc0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 000000000004a9df RCX: 00000000004143c0
RDX: 000000000000000c RSI: 0000000000000002 RDI: 0000000000a6fdf0
RBP: 00000000000000c2 R08: 0000000000000001 R09: 0000000001d5f940
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000a6fdf0
R13: 0000000000a6fde0 R14: 0000000000000000 R15: 0000000000a6fdf0
Modules linked in:
CR2: 0000000000000007
---[ end trace 130dd6b41d308e67 ]---
RIP: 0010:prepare_exit_to_usermode+0x157/0x3a0 arch/x86/entry/common.c:189
Code: 00 00 00 fc ff df 65 4c 8b 2c 25 c0 1e 02 00 49 8d bd 94 08 00 00 48
89 fa 48 c1 ea 03 0f b6 14 02 48 89 f8 83 e0 07 83 c0 03 <38> 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
RSP: 0000:ffffc90001ea7f28 EFLAGS: 00010002
RAX: 0000000000000007 RBX: ffff88805d892000 RCX: ffffffff81009b3f
RDX: 0000000000000000 RSI: ffffffff81009b49 RDI: ffff88805d892894
RBP: ffffc90001ea7f48 R08: ffff88805d892000 R09: ffffed100bb12401
R10: ffffed100bb12400 R11: ffff88805d892007 R12: ffffc90001ea7f58
R13: ffff88805d892000 R14: 0000000000000000 R15: 0000000000000000
FS: 0000000001d5f940(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000007 CR3: 000000005d849000 CR4: 00000000001426f0
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.