KASAN: unknown-crash Write in do_ip6t_set

KASAN: unknown-crash Write in do_ip6t_set_ctl
Status: moderation: reported on 2020/08/30 08:58
Reported-by: syzbot+d9c8758a309a4217d69f@syzkaller.appspotmail.com
First crash: 33d, last: 33d

Sample crash report:

==================================================================
BUG: KASAN: unknown-crash in instrument_copy_from_user include/linux/instrumented.h:105 [inline]
BUG: KASAN: unknown-crash in _copy_from_user+0x10f/0x190 lib/usercopy.c:14
Write of size 536870847 at addr ffffc900181e9040 by task syz-executor.2/10881

CPU: 1 PID: 10881 Comm: syz-executor.2 Not tainted 5.9.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x18f/0x20d lib/dump_stack.c:118
 print_address_description.constprop.0.cold+0x5/0x497 mm/kasan/report.c:383
 __kasan_report mm/kasan/report.c:513 [inline]
 kasan_report.cold+0x1f/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
 instrument_copy_from_user include/linux/instrumented.h:105 [inline]
 _copy_from_user+0x10f/0x190 lib/usercopy.c:14
 copy_from_user include/linux/uaccess.h:160 [inline]
 copy_from_sockptr_offset include/linux/sockptr.h:48 [inline]
 do_replace net/ipv6/netfilter/ip6_tables.c:1146 [inline]
 do_ip6t_set_ctl+0x8b3/0xb73 net/ipv6/netfilter/ip6_tables.c:1636
 nf_setsockopt+0x83/0xe0 net/netfilter/nf_sockopt.c:101
 ipv6_setsockopt+0x122/0x180 net/ipv6/ipv6_sockglue.c:1008
 udpv6_setsockopt+0x76/0xc0 net/ipv6/udp.c:1626
 __sys_setsockopt+0x2db/0x610 net/socket.c:2132
 __do_sys_setsockopt net/socket.c:2143 [inline]
 __se_sys_setsockopt net/socket.c:2140 [inline]
 __x64_sys_setsockopt+0xba/0x150 net/socket.c:2140
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45d579
Code: 5d b4 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 2b b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffb8b0dac78 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 000000000002dbc0 RCX: 000000000045d579
RDX: 0000000000000040 RSI: 0000000000000029 RDI: 0000000000000003
RBP: 000000000118cf90 R08: 0000000000000360 R09: 0000000000000000
R10: 0000000020000800 R11: 0000000000000246 R12: 000000000118cf4c
R13: 000000000169fb6f R14: 00007ffb8b0db9c0 R15: 000000000118cf4c


Memory state around the buggy address:
 ffffc90037109c00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc90037109c80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffffc90037109d00: 00 00 00 00 00 70 07 00 00 70 07 00 77 00 70 07
                                  ^
 ffffc90037109d80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc90037109e00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================

Crashes (1):
Manager	Time	Kernel	Commit	Syzkaller	Config	Log	Report	Syz repro	C repro	VM info	Maintainers
ci-upstream-kasan-gce	2020/08/26 08:47	upstream	abb3438d	344da168	.config	log	report				coreteam@netfilter.org, davem@davemloft.net, fw@strlen.de, kadlec@netfilter.org, kuba@kernel.org, kuznet@ms2.inr.ac.ru, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, netfilter-devel@vger.kernel.org, pablo@netfilter.org, yoshfuji@linux-ipv6.org