WARNING in packet_set_ring

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: b68e78cf BACKPORT: arm64/vdso: Fix nsec handling for CLOCK..
git tree: android-4.4
console output: https://syzkaller.appspot.com/x/log.txt?x=10200f0a400000
kernel config: https://syzkaller.appspot.com/x/.config?x=7e912d922815a1c1
dashboard link: https://syzkaller.appspot.com/bug?extid=713afbc64dad9f0c52f0
compiler: gcc (GCC) 8.0.1 20180413 (experimental)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=141874da400000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=12dc8301400000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+713afb...@syzkaller.appspotmail.com

------------[ cut here ]------------
WARNING: CPU: 1 PID: 2077 at net/packet/af_packet.c:4163
packet_set_ring+0x12f5/0x1820 net/packet/af_packet.c:4163()
Tx-ring is not supported.
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 2077 Comm: syz-executor774 Not tainted 4.4.154+ #97
0000000000000000 f06795b83c6c2e48 ffff8800b6b67938 ffffffff81a54fed
ffffffff82835440 ffff8801d5810000 ffffffff82aa7600 0000000000000009
0000000000001043 ffff8800b6b679f8 ffffffff8138a884 0000000041b58ab3
Call Trace:
[<ffffffff81a54fed>] __dump_stack lib/dump_stack.c:15 [inline]
[<ffffffff81a54fed>] dump_stack+0xc1/0x124 lib/dump_stack.c:51
[<ffffffff8138a884>] panic+0x19e/0x359 kernel/panic.c:112
[<ffffffff8138aa74>] warn_slowpath_common.cold.6+0x20/0x20
kernel/panic.c:455
[<ffffffff810d164f>] warn_slowpath_fmt+0xbf/0x100 kernel/panic.c:471
[<ffffffff8264e5c5>] packet_set_ring+0x12f5/0x1820
net/packet/af_packet.c:4163
[<ffffffff8264faac>] packet_setsockopt+0x5cc/0x22c0
net/packet/af_packet.c:3606
[<ffffffff8215efb6>] SYSC_setsockopt net/socket.c:1780 [inline]
[<ffffffff8215efb6>] SyS_setsockopt+0x166/0x260 net/socket.c:1759
[<ffffffff82690521>] entry_SYSCALL_64_fastpath+0x1e/0x9a
Dumping ftrace buffer:
(ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..


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