From: Hillf Danton hdanton@sina.com
commit b4faef1739dd1f3b3981b8bf173a2266ea86b1eb upstream.
A case of warning was reported by syzbot.
------------[ cut here ]------------ WARNING: CPU: 0 PID: 19934 at net/netfilter/nf_nat_core.c:1106 nf_nat_unregister_fn+0x532/0x5c0 net/netfilter/nf_nat_core.c:1106 Kernel panic - not syncing: panic_on_warn set ... CPU: 0 PID: 19934 Comm: syz-executor.5 Not tainted 5.6.0-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+0x188/0x20d lib/dump_stack.c:118 panic+0x2e3/0x75c kernel/panic.c:221 __warn.cold+0x2f/0x35 kernel/panic.c:582 report_bug+0x27b/0x2f0 lib/bug.c:195 fixup_bug arch/x86/kernel/traps.c:175 [inline] fixup_bug arch/x86/kernel/traps.c:170 [inline] do_error_trap+0x12b/0x220 arch/x86/kernel/traps.c:267 do_invalid_op+0x32/0x40 arch/x86/kernel/traps.c:286 invalid_op+0x23/0x30 arch/x86/entry/entry_64.S:1027 RIP: 0010:nf_nat_unregister_fn+0x532/0x5c0 net/netfilter/nf_nat_core.c:1106 Code: ff df 48 c1 ea 03 80 3c 02 00 75 75 48 8b 44 24 10 4c 89 ef 48 c7 00 00 00 00 00 e8 e8 f8 53 fb e9 4d fe ff ff e8 ee 9c 16 fb <0f> 0b e9 41 fe ff ff e8 e2 45 54 fb e9 b5 fd ff ff 48 8b 7c 24 20 RSP: 0018:ffffc90005487208 EFLAGS: 00010246 RAX: 0000000000040000 RBX: 0000000000000004 RCX: ffffc9001444a000 RDX: 0000000000040000 RSI: ffffffff865c94a2 RDI: 0000000000000005 RBP: ffff88808b5cf000 R08: ffff8880a2620140 R09: fffffbfff14bcd79 R10: ffffc90005487208 R11: fffffbfff14bcd78 R12: 0000000000000000 R13: 0000000000000001 R14: 0000000000000001 R15: 0000000000000000 nf_nat_ipv6_unregister_fn net/netfilter/nf_nat_proto.c:1017 [inline] nf_nat_inet_register_fn net/netfilter/nf_nat_proto.c:1038 [inline] nf_nat_inet_register_fn+0xfc/0x140 net/netfilter/nf_nat_proto.c:1023 nf_tables_register_hook net/netfilter/nf_tables_api.c:224 [inline] nf_tables_addchain.constprop.0+0x82e/0x13c0 net/netfilter/nf_tables_api.c:1981 nf_tables_newchain+0xf68/0x16a0 net/netfilter/nf_tables_api.c:2235 nfnetlink_rcv_batch+0x83a/0x1610 net/netfilter/nfnetlink.c:433 nfnetlink_rcv_skb_batch net/netfilter/nfnetlink.c:543 [inline] nfnetlink_rcv+0x3af/0x420 net/netfilter/nfnetlink.c:561 netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline] netlink_unicast+0x537/0x740 net/netlink/af_netlink.c:1329 netlink_sendmsg+0x882/0xe10 net/netlink/af_netlink.c:1918 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:672 ____sys_sendmsg+0x6bf/0x7e0 net/socket.c:2362 ___sys_sendmsg+0x100/0x170 net/socket.c:2416 __sys_sendmsg+0xec/0x1b0 net/socket.c:2449 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3
and to quiesce it, unregister NFPROTO_IPV6 hook instead of NFPROTO_INET in case of failing to register NFPROTO_IPV4 hook.
Reported-by: syzbot syzbot+33e06702fd6cffc24c40@syzkaller.appspotmail.com Fixes: d164385ec572 ("netfilter: nat: add inet family nat support") Cc: Florian Westphal fw@strlen.de Cc: Stefano Brivio sbrivio@redhat.com Signed-off-by: Hillf Danton hdanton@sina.com Signed-off-by: Pablo Neira Ayuso pablo@netfilter.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- net/netfilter/nf_nat_proto.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
--- a/net/netfilter/nf_nat_proto.c +++ b/net/netfilter/nf_nat_proto.c @@ -1035,8 +1035,8 @@ int nf_nat_inet_register_fn(struct net * ret = nf_nat_register_fn(net, NFPROTO_IPV4, ops, nf_nat_ipv4_ops, ARRAY_SIZE(nf_nat_ipv4_ops)); if (ret) - nf_nat_ipv6_unregister_fn(net, ops); - + nf_nat_unregister_fn(net, NFPROTO_IPV6, ops, + ARRAY_SIZE(nf_nat_ipv6_ops)); return ret; } EXPORT_SYMBOL_GPL(nf_nat_inet_register_fn);