WARNING in skb_warn_bad_offload

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: e1f7d50a Linux 4.14.160
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=13d2bc3ee00000
kernel config: https://syzkaller.appspot.com/x/.config?x=46599517442ad9fb
dashboard link: https://syzkaller.appspot.com/bug?extid=c75af286bcfa9fb5ac5b
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+c75af2...@syzkaller.appspotmail.com

loop2: partition table beyond EOD, truncated
: caps=(0x0000000000000000, 0x00000144401d7c69) len=572 data_len=0
gso_size=104 gso_type=1 ip_summed=3
------------[ cut here ]------------
WARNING: CPU: 1 PID: 13985 at net/core/dev.c:2613
skb_warn_bad_offload.cold+0x1d7/0x454 net/core/dev.c:2613
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 13985 Comm: syz-executor.2 Not tainted 4.14.160-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:17 [inline]
dump_stack+0x142/0x197 lib/dump_stack.c:58
panic+0x1f9/0x42d kernel/panic.c:183
kobject: 'loop3' (ffff8880a416ac60): kobject_uevent_env
__warn.cold+0x2f/0x2f kernel/panic.c:547
kobject: 'loop3' (ffff8880a416ac60): fill_kobj_path: path
= '/devices/virtual/block/loop3'
report_bug+0x216/0x254 lib/bug.c:186
fixup_bug arch/x86/kernel/traps.c:177 [inline]
fixup_bug arch/x86/kernel/traps.c:172 [inline]
do_error_trap+0x1bb/0x310 arch/x86/kernel/traps.c:295
do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:314
invalid_op+0x1b/0x40 arch/x86/entry/entry_64.S:963
RIP: 0010:skb_warn_bad_offload.cold+0x1d7/0x454 net/core/dev.c:2613
kobject: 'loop0' (ffff8880a409f3a0): kobject_uevent_env
RSP: 0018:ffff888053ac7368 EFLAGS: 00010286
RAX: 0000000000000066 RBX: ffff88804fdf6328 RCX: 0000000000000000
RDX: 000000000000ec4d RSI: ffffffff814b9365 RDI: ffffed100a758e63
RBP: ffff888053ac73b8 R08: 0000000000000066 R09: ffff88809e2bcca0
R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff875893e0
R13: ffffffff875876e0 R14: 0000000000000000 R15: 000000000000023c
skb_checksum_help+0x61b/0x850 net/core/dev.c:2634
kobject: 'loop0' (ffff8880a409f3a0): fill_kobj_path: path
= '/devices/virtual/block/loop0'
checksum_tg+0x5c/0x71 net/netfilter/xt_CHECKSUM.c:29
ipt_do_table+0xafd/0x1770 net/ipv4/netfilter/ip_tables.c:353
ipt_mangle_out net/ipv4/netfilter/iptable_mangle.c:64 [inline]
iptable_mangle_hook+0x2dc/0x570 net/ipv4/netfilter/iptable_mangle.c:89
nf_hook_entry_hookfn include/linux/netfilter.h:108 [inline]
nf_hook_slow+0xaf/0x1b0 net/netfilter/core.c:467
nf_hook include/linux/netfilter.h:205 [inline]
__ip_local_out+0x38c/0x820 net/ipv4/ip_output.c:113
ip_local_out+0x29/0x170 net/ipv4/ip_output.c:122
ip_queue_xmit+0x7d7/0x1b10 net/ipv4/ip_output.c:504
__tcp_transmit_skb+0x1721/0x2fd0 net/ipv4/tcp_output.c:1131
protocol 88fb is buggy, dev hsr_slave_0
tcp_transmit_skb net/ipv4/tcp_output.c:1147 [inline]
tcp_write_xmit+0x523/0x49b0 net/ipv4/tcp_output.c:2383
tcp_push_one+0xc1/0xf0 net/ipv4/tcp_output.c:2578
protocol 88fb is buggy, dev hsr_slave_1
tcp_sendmsg_locked+0x1584/0x31c0 net/ipv4/tcp.c:1406
tcp_sendmsg+0x30/0x50 net/ipv4/tcp.c:1457
inet_sendmsg+0x122/0x500 net/ipv4/af_inet.c:762
sock_sendmsg_nosec net/socket.c:646 [inline]
sock_sendmsg+0xce/0x110 net/socket.c:656
SYSC_sendto+0x206/0x310 net/socket.c:1763
kobject: 'loop1' (ffff8880a40e82e0): kobject_uevent_env
SyS_sendto+0x40/0x50 net/socket.c:1731
do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
kobject: 'loop1' (ffff8880a40e82e0): fill_kobj_path: path
= '/devices/virtual/block/loop1'
entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x45a919
RSP: 002b:00007f2174d43c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 000000000045a919
RDX: 0000000000008293 RSI: 0000000020000180 RDI: 000000000000000a
RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000027
R10: 0000000004000002 R11: 0000000000000246 R12: 00007f2174d446d4
R13: 00000000004c9ab3 R14: 00000000004e1a20 R15: 00000000ffffffff
Kernel Offset: disabled
Rebooting in 86400 seconds..


---
This bug is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
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[syzbot]

syzbot has found a reproducer for the following crash on:

HEAD commit: e1f7d50a Linux 4.14.160
git tree: linux-4.14.y

console output: https://syzkaller.appspot.com/x/log.txt?x=13a391fee00000

kernel config: https://syzkaller.appspot.com/x/.config?x=46599517442ad9fb
dashboard link: https://syzkaller.appspot.com/bug?extid=c75af286bcfa9fb5ac5b
compiler: gcc (GCC) 9.0.0 20181231 (experimental)

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=16cffa15e00000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=173252c6e00000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+c75af2...@syzkaller.appspotmail.com

audit: type=1400 audit(1577286797.291:36): avc: denied { map } for
pid=7067 comm="syz-executor926" path="/root/syz-executor926738089"
dev="sda1" ino=16484 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023
tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1
ip_tables: iptables: counters copy to user failed while replacing table

: caps=(0x0000000000000000, 0x00000144401d7c69) len=572 data_len=0
gso_size=104 gso_type=1 ip_summed=3
------------[ cut here ]------------

WARNING: CPU: 1 PID: 7067 at net/core/dev.c:2613

skb_warn_bad_offload.cold+0x1d7/0x454 net/core/dev.c:2613
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 7067 Comm: syz-executor926 Not tainted 4.14.160-syzkaller #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:17 [inline]
dump_stack+0x142/0x197 lib/dump_stack.c:58
panic+0x1f9/0x42d kernel/panic.c:183

__warn.cold+0x2f/0x2f kernel/panic.c:547

report_bug+0x216/0x254 lib/bug.c:186
fixup_bug arch/x86/kernel/traps.c:177 [inline]
fixup_bug arch/x86/kernel/traps.c:172 [inline]
do_error_trap+0x1bb/0x310 arch/x86/kernel/traps.c:295
do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:314
invalid_op+0x1b/0x40 arch/x86/entry/entry_64.S:963
RIP: 0010:skb_warn_bad_offload.cold+0x1d7/0x454 net/core/dev.c:2613

RSP: 0018:ffff88807c79f368 EFLAGS: 00010286
RAX: 0000000000000066 RBX: ffff88808bc38da8 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffff888090026950 RDI: ffffed100f8f3e63
RBP: ffff88807c79f3b8 R08: 0000000000000066 R09: ffff888090026920

R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff875893e0
R13: ffffffff875876e0 R14: 0000000000000000 R15: 000000000000023c
skb_checksum_help+0x61b/0x850 net/core/dev.c:2634

checksum_tg+0x5c/0x71 net/netfilter/xt_CHECKSUM.c:29
ipt_do_table+0xafd/0x1770 net/ipv4/netfilter/ip_tables.c:353
ipt_mangle_out net/ipv4/netfilter/iptable_mangle.c:64 [inline]
iptable_mangle_hook+0x2dc/0x570 net/ipv4/netfilter/iptable_mangle.c:89
nf_hook_entry_hookfn include/linux/netfilter.h:108 [inline]
nf_hook_slow+0xaf/0x1b0 net/netfilter/core.c:467
nf_hook include/linux/netfilter.h:205 [inline]
__ip_local_out+0x38c/0x820 net/ipv4/ip_output.c:113
ip_local_out+0x29/0x170 net/ipv4/ip_output.c:122
ip_queue_xmit+0x7d7/0x1b10 net/ipv4/ip_output.c:504
__tcp_transmit_skb+0x1721/0x2fd0 net/ipv4/tcp_output.c:1131

tcp_transmit_skb net/ipv4/tcp_output.c:1147 [inline]
tcp_write_xmit+0x523/0x49b0 net/ipv4/tcp_output.c:2383
tcp_push_one+0xc1/0xf0 net/ipv4/tcp_output.c:2578

tcp_sendmsg_locked+0x1584/0x31c0 net/ipv4/tcp.c:1406
tcp_sendmsg+0x30/0x50 net/ipv4/tcp.c:1457
inet_sendmsg+0x122/0x500 net/ipv4/af_inet.c:762
sock_sendmsg_nosec net/socket.c:646 [inline]
sock_sendmsg+0xce/0x110 net/socket.c:656
SYSC_sendto+0x206/0x310 net/socket.c:1763

SyS_sendto+0x40/0x50 net/socket.c:1731
do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292

entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x441689
RSP: 002b:00007ffc11b90838 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000441689
RDX: 0000000000008293 RSI: 0000000020000180 RDI: 0000000000000004
RBP: 00000000006cb018 R08: 0000000000000000 R09: 0000000000000027
R10: 0000000004000002 R11: 0000000000000246 R12: 0000000000402f10
R13: 0000000000402fa0 R14: 0000000000000000 R15: 0000000000000000