KASAN: wild-memory-access Read in do_ebt_set_ctl

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    86cfccb6 Merge tag 'dlm-5.9' of git://git.kernel.org/pub/s..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1419de8a900000
kernel config:  https://syzkaller.appspot.com/x/.config?x=bcf489e08c9b8c5e
dashboard link: https://syzkaller.appspot.com/bug?extid=64d60892aaa4d4c34812
compiler:       gcc (GCC) 10.1.0-syz 20200507
userspace arch: i386

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+64d60892aaa4d4c34812@xxxxxxxxxxxxxxxxxxxxxxxxx

BUG: KASAN: wild-memory-access in memcpy include/linux/string.h:406 [inline]
BUG: KASAN: wild-memory-access in copy_from_sockptr_offset include/linux/sockptr.h:71 [inline]
BUG: KASAN: wild-memory-access in copy_from_sockptr include/linux/sockptr.h:77 [inline]
BUG: KASAN: wild-memory-access in compat_update_counters net/bridge/netfilter/ebtables.c:2222 [inline]
BUG: KASAN: wild-memory-access in do_ebt_set_ctl+0x2c0/0x53b net/bridge/netfilter/ebtables.c:2389
Read of size 80 at addr 00000000ffffffff by task syz-executor.3/9621

CPU: 1 PID: 9621 Comm: syz-executor.3 Not tainted 5.8.0-syzkaller #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x18f/0x20d lib/dump_stack.c:118
 __kasan_report mm/kasan/report.c:517 [inline]
 kasan_report.cold+0x5/0x37 mm/kasan/report.c:530
 check_memory_region_inline mm/kasan/generic.c:186 [inline]
 check_memory_region+0x13d/0x180 mm/kasan/generic.c:192
 memcpy+0x20/0x60 mm/kasan/common.c:105
 memcpy include/linux/string.h:406 [inline]
 copy_from_sockptr_offset include/linux/sockptr.h:71 [inline]
 copy_from_sockptr include/linux/sockptr.h:77 [inline]
 compat_update_counters net/bridge/netfilter/ebtables.c:2222 [inline]
 do_ebt_set_ctl+0x2c0/0x53b net/bridge/netfilter/ebtables.c:2389
 nf_setsockopt+0x6f/0xc0 net/netfilter/nf_sockopt.c:101
 ip_setsockopt+0x54d/0x3c10 net/ipv4/ip_sockglue.c:1436
 raw_setsockopt+0x205/0x250 net/ipv4/raw.c:856
 __sys_setsockopt+0x2ad/0x6d0 net/socket.c:2138
 __do_sys_setsockopt net/socket.c:2149 [inline]
 __se_sys_setsockopt net/socket.c:2146 [inline]
 __ia32_sys_setsockopt+0xb9/0x150 net/socket.c:2146
 do_syscall_32_irqs_on arch/x86/entry/common.c:84 [inline]
 __do_fast_syscall_32+0x57/0x80 arch/x86/entry/common.c:126
 do_fast_syscall_32+0x2f/0x70 arch/x86/entry/common.c:149
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c
RIP: 0023:0xf7f19569
Code: c4 01 10 03 03 74 c0 01 10 05 03 74 b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 002b:00000000f55130bc EFLAGS: 00000296 ORIG_RAX: 000000000000016e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000000000
RDX: 0000000000000081 RSI: 00000000ffffffff RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
==================================================================


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