general protection fault in kernel_get_mempolicy

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit:    bef7b2a7 Merge tag 'devicetree-for-5.7' of git://git.kerne..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=124974e7e00000
kernel config:  https://syzkaller.appspot.com/x/.config?x=91b674b8f0368e69
dashboard link: https://syzkaller.appspot.com/bug?extid=ceba41fd2d12f822c1bd
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+ceba41fd2d12f822c1bd@xxxxxxxxxxxxxxxxxxxxxxxxx

general protection fault, probably for non-canonical address 0xf223931c0412cd20: 0000 [#1] PREEMPT SMP KASAN
KASAN: maybe wild-memory-access in range [0x911cb8e020966900-0x911cb8e020966907]
CPU: 1 PID: 21483 Comm: syz-executor.5 Not tainted 5.6.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:page_to_nid include/linux/mm.h:1245 [inline]
RIP: 0010:lookup_node mm/mempolicy.c:906 [inline]
RIP: 0010:do_get_mempolicy mm/mempolicy.c:970 [inline]
RIP: 0010:kernel_get_mempolicy+0x604/0xfb0 mm/mempolicy.c:1615
Code: 89 c7 e8 2f 37 c5 ff 85 db 0f 88 00 07 00 00 e8 b2 35 c5 ff 4c 8b 7c 24 78 48 b8 00 00 00 00 00 fc ff df 4c 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 fb 08 00 00 49 8b 1f 48 c7 c7 ff ff ff ff 48 89
RSP: 0018:ffffc900055e7de8 EFLAGS: 00010a02
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffc90013b96000
RDX: 1223971c0412cd20 RSI: ffffffff81adaafe RDI: 0000000000000005
RBP: 0000000000000000 R08: ffff88802e0fe380 R09: ffffed1005c1fc71
R10: ffff88802e0fe387 R11: ffffed1005c1fc70 R12: 0000000000000000
R13: 1ffff92000abcfc4 R14: ffffffff89a6df60 R15: 911cb8e020966900
FS:  00007f93143f7700(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b30b23000 CR3: 0000000052590000 CR4: 00000000001426e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 __do_sys_get_mempolicy mm/mempolicy.c:1633 [inline]
 __se_sys_get_mempolicy mm/mempolicy.c:1629 [inline]
 __x64_sys_get_mempolicy+0xba/0x150 mm/mempolicy.c:1629
 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x49/0xb3
RIP: 0033:0x45c849
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:00007f93143f6c78 EFLAGS: 00000246 ORIG_RAX: 00000000000000ef
RAX: ffffffffffffffda RBX: 00007f93143f76d4 RCX: 000000000045c849
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 000000000076bf00 R08: 0000000000000003 R09: 0000000000000000
R10: 000000002073b000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000000eb R14: 00000000004c371a R15: 000000000076bf0c
Modules linked in:
---[ end trace 4f30e35dce9f5dd6 ]---
RIP: 0010:page_to_nid include/linux/mm.h:1245 [inline]
RIP: 0010:lookup_node mm/mempolicy.c:906 [inline]
RIP: 0010:do_get_mempolicy mm/mempolicy.c:970 [inline]
RIP: 0010:kernel_get_mempolicy+0x604/0xfb0 mm/mempolicy.c:1615
Code: 89 c7 e8 2f 37 c5 ff 85 db 0f 88 00 07 00 00 e8 b2 35 c5 ff 4c 8b 7c 24 78 48 b8 00 00 00 00 00 fc ff df 4c 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 fb 08 00 00 49 8b 1f 48 c7 c7 ff ff ff ff 48 89
RSP: 0018:ffffc900055e7de8 EFLAGS: 00010a02
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffc90013b96000
RDX: 1223971c0412cd20 RSI: ffffffff81adaafe RDI: 0000000000000005
RBP: 0000000000000000 R08: ffff88802e0fe380 R09: ffffed1005c1fc71
R10: ffff88802e0fe387 R11: ffffed1005c1fc70 R12: 0000000000000000
R13: 1ffff92000abcfc4 R14: ffffffff89a6df60 R15: 911cb8e020966900
FS:  00007f93143f7700(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f535ca3c000 CR3: 0000000052590000 CR4: 00000000001426f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


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