syzbot

BUG: unable to handle page fault for address: ffff8880bfffd000
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 10601067 P4D 10601067 PUD 23ffff067 PMD 23fffe067 PTE 0
Oops: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 8661 Comm: syz-executor159 Not tainted 5.14.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:do_csum+0x177/0x400 arch/x86/lib/csum-partial_64.c:72
Code: 89 ee 44 89 6c 24 04 89 04 24 e8 c4 01 80 fd 45 85 ed 74 4e 4d 89 e6 e8 07 f9 7f fd 41 83 ed 01 31 ff 31 c0 44 89 ee 49 03 1e <49> 13 5e 08 49 13 5e 10 49 13 5e 18 49 13 5e 20 49 13 5e 28 49 13
RSP: 0018:ffffc900023f7420 EFLAGS: 00010282
RAX: 0000000000000000 RBX: a3c915ee7fd7fcdc RCX: 0000000000000000
RDX: ffff8880305c2240 RSI: 0000000002088401 RDI: 0000000000000000
RBP: 00000000ffffffec R08: 0000000000000000 R09: 0000000000000060
R10: ffffffff83f4e59b R11: 0000000000000060 R12: ffff88804220d0b8
R13: 0000000002088401 R14: ffff8880bfffcff8 R15: 0000000000000000
FS:  00007f002bbd7700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffff8880bfffd000 CR3: 000000003987f000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 csum_partial+0x1c/0x30 arch/x86/lib/csum-partial_64.c:136
 lco_csum include/linux/skbuff.h:4662 [inline]
 gre_build_header include/net/gre.h:139 [inline]
 __gre_xmit+0x879/0x970 net/ipv4/ip_gre.c:467
 ipgre_xmit+0x679/0x830 net/ipv4/ip_gre.c:653
 __netdev_start_xmit include/linux/netdevice.h:4944 [inline]
 netdev_start_xmit include/linux/netdevice.h:4958 [inline]
 xmit_one net/core/dev.c:3659 [inline]
 dev_hard_start_xmit+0x1eb/0x920 net/core/dev.c:3675
 __dev_queue_xmit+0x2988/0x3620 net/core/dev.c:4285
 packet_snd net/packet/af_packet.c:3016 [inline]
 packet_sendmsg+0x22fc/0x52b0 net/packet/af_packet.c:3044
 sock_sendmsg_nosec net/socket.c:703 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:723
 sock_no_sendpage+0xf3/0x130 net/core/sock.c:2959
 kernel_sendpage.part.0+0x1a0/0x340 net/socket.c:3673
 kernel_sendpage net/socket.c:3670 [inline]
 sock_sendpage+0xe5/0x140 net/socket.c:1002
 pipe_to_sendpage+0x2ad/0x380 fs/splice.c:364
 splice_from_pipe_feed fs/splice.c:418 [inline]
 __splice_from_pipe+0x43e/0x8a0 fs/splice.c:562
 splice_from_pipe fs/splice.c:597 [inline]
 generic_splice_sendpage+0xd4/0x140 fs/splice.c:746
 do_splice_from fs/splice.c:767 [inline]
 do_splice+0xb7e/0x1960 fs/splice.c:1079
 __do_splice+0x134/0x250 fs/splice.c:1144
 __do_sys_splice fs/splice.c:1350 [inline]
 __se_sys_splice fs/splice.c:1332 [inline]
 __x64_sys_splice+0x198/0x250 fs/splice.c:1332
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x449009
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 a1 15 00 00 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 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f002bbd72e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000113
RAX: ffffffffffffffda RBX: 00000000004cf510 RCX: 0000000000449009
RDX: 0000000000000006 RSI: 0000000000000000 RDI: 0000000000000004
RBP: 00000000004cf51c R08: 00000000ffffffff R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000049e004
R13: 78902f0000000000 R14: 6d32cc5e8ead0600 R15: 00000000004cf518
Modules linked in:
CR2: ffff8880bfffd000
---[ end trace 100fcbab8ee0a232 ]---
RIP: 0010:do_csum+0x177/0x400 arch/x86/lib/csum-partial_64.c:72
Code: 89 ee 44 89 6c 24 04 89 04 24 e8 c4 01 80 fd 45 85 ed 74 4e 4d 89 e6 e8 07 f9 7f fd 41 83 ed 01 31 ff 31 c0 44 89 ee 49 03 1e <49> 13 5e 08 49 13 5e 10 49 13 5e 18 49 13 5e 20 49 13 5e 28 49 13
RSP: 0018:ffffc900023f7420 EFLAGS: 00010282
RAX: 0000000000000000 RBX: a3c915ee7fd7fcdc RCX: 0000000000000000
RDX: ffff8880305c2240 RSI: 0000000002088401 RDI: 0000000000000000
RBP: 00000000ffffffec R08: 0000000000000000 R09: 0000000000000060
R10: ffffffff83f4e59b R11: 0000000000000060 R12: ffff88804220d0b8
R13: 0000000002088401 R14: ffff8880bfffcff8 R15: 0000000000000000
FS:  00007f002bbd7700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffff8880bfffd000 CR3: 000000003987f000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	89 ee                	mov    %ebp,%esi
   2:	44 89 6c 24 04       	mov    %r13d,0x4(%rsp)
   7:	89 04 24             	mov    %eax,(%rsp)
   a:	e8 c4 01 80 fd       	callq  0xfd8001d3
   f:	45 85 ed             	test   %r13d,%r13d
  12:	74 4e                	je     0x62
  14:	4d 89 e6             	mov    %r12,%r14
  17:	e8 07 f9 7f fd       	callq  0xfd7ff923
  1c:	41 83 ed 01          	sub    $0x1,%r13d
  20:	31 ff                	xor    %edi,%edi
  22:	31 c0                	xor    %eax,%eax
  24:	44 89 ee             	mov    %r13d,%esi
  27:	49 03 1e             	add    (%r14),%rbx
  2a:	49 13 5e 08          	adc    0x8(%r14),%rbx <-- trapping instruction
  2e:	49 13 5e 10          	adc    0x10(%r14),%rbx
  32:	49 13 5e 18          	adc    0x18(%r14),%rbx
  36:	49 13 5e 20          	adc    0x20(%r14),%rbx
  3a:	49 13 5e 28          	adc    0x28(%r14),%rbx
  3e:	49                   	rex.WB
  3f:	13                   	.byte 0x13