general protection fault in xt_rateest_put

From: syzbot
Date: Sat Jan 11 2020 - 13:04:13 EST


Hello,

syzbot found the following crash on:

HEAD commit: e69ec487 Merge branch 'for-linus' of git://git.kernel.org/..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1239f876e00000
kernel config: https://syzkaller.appspot.com/x/.config?x=18698c0c240ba616
dashboard link: https://syzkaller.appspot.com/bug?extid=91bdd8eece0f6629ec8b
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13dbd58ee00000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=15eff9e1e00000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+91bdd8eece0f6629ec8b@xxxxxxxxxxxxxxxxxxxxxxxxx

kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 10213 Comm: syz-executor519 Not tainted 5.5.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__read_once_size include/linux/compiler.h:199 [inline]
RIP: 0010:net_generic include/net/netns/generic.h:45 [inline]
RIP: 0010:xt_rateest_put+0xa1/0x440 net/netfilter/xt_RATEEST.c:77
Code: 85 87 01 fb 45 84 f6 0f 84 68 02 00 00 e8 37 86 01 fb 49 8d bd 68 13 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 6c 03 00 00 4d 8b b5 68 13 00 00 e8 29 bf ed fa
RSP: 0018:ffffc90001cd7940 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffff8880a779f700 RCX: ffffffff8673a332
RDX: 000000000000026d RSI: ffffffff8673a0b9 RDI: 0000000000001368
RBP: ffffc90001cd7970 R08: ffff8880a96b2240 R09: ffffed1015d0703d
R10: ffffed1015d0703c R11: ffff8880ae8381e3 R12: 000000000000002d
R13: 0000000000000000 R14: 0000000000000001 R15: ffffffff8673a470
FS: 00000000016ce880(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055cd48aff140 CR3: 0000000096982000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
xt_rateest_tg_destroy+0x72/0xa0 net/netfilter/xt_RATEEST.c:175
cleanup_entry net/ipv4/netfilter/arp_tables.c:509 [inline]
translate_table+0x11f4/0x1d80 net/ipv4/netfilter/arp_tables.c:587
do_replace net/ipv4/netfilter/arp_tables.c:981 [inline]
do_arpt_set_ctl+0x317/0x650 net/ipv4/netfilter/arp_tables.c:1461
nf_sockopt net/netfilter/nf_sockopt.c:106 [inline]
nf_setsockopt+0x77/0xd0 net/netfilter/nf_sockopt.c:115
ip_setsockopt net/ipv4/ip_sockglue.c:1260 [inline]
ip_setsockopt+0xdf/0x100 net/ipv4/ip_sockglue.c:1240
udp_setsockopt+0x68/0xb0 net/ipv4/udp.c:2639
sock_common_setsockopt+0x94/0xd0 net/core/sock.c:3149
__sys_setsockopt+0x261/0x4c0 net/socket.c:2117
__do_sys_setsockopt net/socket.c:2133 [inline]
__se_sys_setsockopt net/socket.c:2130 [inline]
__x64_sys_setsockopt+0xbe/0x150 net/socket.c:2130
do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x441699
Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 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 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffc35157368 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000441699
RDX: 0000000000000060 RSI: 0a02000000000000 RDI: 0000000000000003
RBP: 00000000006cb018 R08: 0000000000000430 R09: 00000000004002c8
R10: 00000000200008c0 R11: 0000000000000246 R12: 0000000000402f20
R13: 0000000000402fb0 R14: 0000000000000000 R15: 0000000000000000
Modules linked in:
---[ end trace f2341320b9d5ba2d ]---
RIP: 0010:__read_once_size include/linux/compiler.h:199 [inline]
RIP: 0010:net_generic include/net/netns/generic.h:45 [inline]
RIP: 0010:xt_rateest_put+0xa1/0x440 net/netfilter/xt_RATEEST.c:77
Code: 85 87 01 fb 45 84 f6 0f 84 68 02 00 00 e8 37 86 01 fb 49 8d bd 68 13 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 6c 03 00 00 4d 8b b5 68 13 00 00 e8 29 bf ed fa
RSP: 0018:ffffc90001cd7940 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffff8880a779f700 RCX: ffffffff8673a332
RDX: 000000000000026d RSI: ffffffff8673a0b9 RDI: 0000000000001368
RBP: ffffc90001cd7970 R08: ffff8880a96b2240 R09: ffffed1015d0703d
R10: ffffed1015d0703c R11: ffff8880ae8381e3 R12: 000000000000002d
R13: 0000000000000000 R14: 0000000000000001 R15: ffffffff8673a470
FS: 00000000016ce880(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055cd48af04c0 CR3: 0000000096982000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


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