BUG: unable to handle kernel paging request in mm_update_next_owner

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: ae83d0b4 Linux 5.7-rc2
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1642dcf7e00000
kernel config: https://syzkaller.appspot.com/x/.config?x=4a2e65056025ac64
dashboard link: https://syzkaller.appspot.com/bug?extid=eadbf36ed45b19216b99
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
CC: [chri...@brauner.io ebie...@xmission.com linux-...@vger.kernel.org mi...@kernel.org ol...@redhat.com pet...@infradead.org tg...@linutronix.de]

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+eadbf3...@syzkaller.appspotmail.com

BUG: unable to handle page fault for address: fffffffffffffe90
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 987c067 P4D 987c067 PUD 987e067 PMD 0
Oops: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 16435 Comm: syz-executor.5 Not tainted 5.7.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:mm_update_next_owner+0x519/0x7a0 kernel/exit.c:386
Code: 68 fa ff ff 49 39 c7 0f 84 eb fe ff ff e8 cf 8e 2d 00 48 8d bd 28 04 00 00 48 89 f8 48 c1 e8 03 80 3c 18 00 0f 85 96 01 00 00 <4c> 8b b5 28 04 00 00 4d 39 e6 75 95 49 89 fd e9 61 fc ff ff e8 9e
RSP: 0018:ffffc900173afd20 EFLAGS: 00010246
RAX: 1fffffffffffffd2 RBX: dffffc0000000000 RCX: ffffffff81459f43
RDX: 0000000000000000 RSI: ffffffff81459fe1 RDI: fffffffffffffe90
RBP: fffffffffffffa68 R08: ffff8881fb296080 R09: fffffbfff1301219
R10: ffffffff898090c3 R11: fffffbfff1301218 R12: ffff8881ff35d1c0
R13: ffff88800015e280 R14: 0000000000000000 R15: ffff8880a36e15d0
FS: 0000000000000000(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: fffffffffffffe90 CR3: 00000001f057e000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
exit_mm kernel/exit.c:478 [inline]
do_exit+0xa49/0x2dd0 kernel/exit.c:782
do_group_exit+0x125/0x340 kernel/exit.c:893
__do_sys_exit_group kernel/exit.c:904 [inline]
__se_sys_exit_group kernel/exit.c:902 [inline]
__x64_sys_exit_group+0x3a/0x50 kernel/exit.c:902
do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295
entry_SYSCALL_64_after_hwframe+0x49/0xb3
RIP: 0033:0x45c829
Code: 0d b7 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 b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:0000000000c9fd88 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 000000000000001e RCX: 000000000045c829
RDX: 0000000000416421 RSI: fffffffffffffff7 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000c9fde0
R10: 0000000000790270 R11: 0000000000000246 R12: 0000000000000001
R13: 0000000000c9fde0 R14: 0000000000000000 R15: 0000000000c9fdf0
Modules linked in:
CR2: fffffffffffffe90
---[ end trace ea314bde5f5f4498 ]---
RIP: 0010:mm_update_next_owner+0x519/0x7a0 kernel/exit.c:386
Code: 68 fa ff ff 49 39 c7 0f 84 eb fe ff ff e8 cf 8e 2d 00 48 8d bd 28 04 00 00 48 89 f8 48 c1 e8 03 80 3c 18 00 0f 85 96 01 00 00 <4c> 8b b5 28 04 00 00 4d 39 e6 75 95 49 89 fd e9 61 fc ff ff e8 9e
RSP: 0018:ffffc900173afd20 EFLAGS: 00010246
RAX: 1fffffffffffffd2 RBX: dffffc0000000000 RCX: ffffffff81459f43
RDX: 0000000000000000 RSI: ffffffff81459fe1 RDI: fffffffffffffe90
RBP: fffffffffffffa68 R08: ffff8881fb296080 R09: fffffbfff1301219
R10: ffffffff898090c3 R11: fffffbfff1301218 R12: ffff8881ff35d1c0
R13: ffff88800015e280 R14: 0000000000000000 R15: ffff8880a36e15d0
FS: 0000000000000000(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: fffffffffffffe90 CR3: 00000001f057e000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


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[syzbot]

Sending this report upstream.