From 7118c07a844d367560ee91adb2071bde2fabcdbf Mon Sep 17 00:00:00 2001 From: Sasha Levin Date: Sat, 14 Apr 2012 12:37:46 -0400 Subject: [PATCH] ipvs: Verify that IP_VS protocol has been registered The registration of a protocol might fail, there were no checks and all registrations were assumed to be correct. This lead to NULL ptr dereferences when apps tried registering. For example: [ 1293.226051] BUG: unable to handle kernel NULL pointer dereference at 0000000000000018 [ 1293.227038] IP: [] tcp_register_app+0x60/0xb0 [ 1293.227038] PGD 391de067 PUD 6c20b067 PMD 0 [ 1293.227038] Oops: 0000 [#1] PREEMPT SMP [ 1293.227038] CPU 1 [ 1293.227038] Pid: 19609, comm: trinity Tainted: G W 3.4.0-rc1-next-20120405-sasha-dirty #57 [ 1293.227038] RIP: 0010:[] [] tcp_register_app+0x60/0xb0 [ 1293.227038] RSP: 0018:ffff880038c1dd18 EFLAGS: 00010286 [ 1293.227038] RAX: ffffffffffffffc0 RBX: 0000000000001500 RCX: 0000000000010000 [ 1293.227038] RDX: 0000000000000000 RSI: ffff88003a2d5888 RDI: 0000000000000282 [ 1293.227038] RBP: ffff880038c1dd48 R08: 0000000000000000 R09: 0000000000000000 [ 1293.227038] R10: 0000000000000000 R11: 0000000000000000 R12: ffff88003a2d5668 [ 1293.227038] R13: ffff88003a2d5988 R14: ffff8800696a8ff8 R15: 0000000000000000 [ 1293.227038] FS: 00007f01930d9700(0000) GS:ffff88007ce00000(0000) knlGS:0000000000000000 [ 1293.227038] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b [ 1293.227038] CR2: 0000000000000018 CR3: 0000000065dfc000 CR4: 00000000000406e0 [ 1293.227038] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 1293.227038] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 [ 1293.227038] Process trinity (pid: 19609, threadinfo ffff880038c1c000, task ffff88002dc73000) [ 1293.227038] Stack: [ 1293.227038] ffff880038c1dd48 00000000fffffff4 ffff8800696aada0 ffff8800694f5580 [ 1293.227038] ffffffff8369f1e0 0000000000001500 ffff880038c1dd98 ffffffff822a716b [ 1293.227038] 0000000000000000 ffff8800696a8ff8 0000000000000015 ffff8800694f5580 [ 1293.227038] Call Trace: [ 1293.227038] [] ip_vs_app_inc_new+0xdb/0x180 [ 1293.227038] [] register_ip_vs_app_inc+0x48/0x70 [ 1293.227038] [] __ip_vs_ftp_init+0xba/0x140 [ 1293.227038] [] ops_init+0x80/0x90 [ 1293.227038] [] setup_net+0x5b/0xe0 [ 1293.227038] [] copy_net_ns+0x76/0x100 [ 1293.227038] [] create_new_namespaces+0xfb/0x190 [ 1293.227038] [] unshare_nsproxy_namespaces+0x61/0x80 [ 1293.227038] [] sys_unshare+0xff/0x290 [ 1293.227038] [] ? trace_hardirqs_on_thunk+0x3a/0x3f [ 1293.227038] [] system_call_fastpath+0x16/0x1b [ 1293.227038] Code: 89 c7 e8 34 91 3b 00 89 de 66 c1 ee 04 31 de 83 e6 0f 48 83 c6 22 48 c1 e6 04 4a 8b 14 26 49 8d 34 34 48 8d 42 c0 48 39 d6 74 13 <66> 39 58 58 74 22 48 8b 48 40 48 8d 41 c0 48 39 ce 75 ed 49 8d [ 1293.227038] RIP [] tcp_register_app+0x60/0xb0 [ 1293.227038] RSP [ 1293.227038] CR2: 0000000000000018 [ 1293.379284] ---[ end trace 364ab40c7011a009 ]--- [ 1293.381182] Kernel panic - not syncing: Fatal exception in interrupt Signed-off-by: Sasha Levin Acked-by: Julian Anastasov Signed-off-by: Simon Horman Signed-off-by: Pablo Neira Ayuso --- net/netfilter/ipvs/ip_vs_proto.c | 27 ++++++++++++++++++--------- 1 file changed, 18 insertions(+), 9 deletions(-) diff --git a/net/netfilter/ipvs/ip_vs_proto.c b/net/netfilter/ipvs/ip_vs_proto.c index f843a8833250..a62360e29037 100644 --- a/net/netfilter/ipvs/ip_vs_proto.c +++ b/net/netfilter/ipvs/ip_vs_proto.c @@ -59,9 +59,6 @@ static int __used __init register_ip_vs_protocol(struct ip_vs_protocol *pp) return 0; } -#if defined(CONFIG_IP_VS_PROTO_TCP) || defined(CONFIG_IP_VS_PROTO_UDP) || \ - defined(CONFIG_IP_VS_PROTO_SCTP) || defined(CONFIG_IP_VS_PROTO_AH) || \ - defined(CONFIG_IP_VS_PROTO_ESP) /* * register an ipvs protocols netns related data */ @@ -86,7 +83,6 @@ register_ip_vs_proto_netns(struct net *net, struct ip_vs_protocol *pp) return 0; } -#endif /* * unregister an ipvs protocol @@ -316,22 +312,35 @@ ip_vs_tcpudp_debug_packet(int af, struct ip_vs_protocol *pp, */ int __net_init ip_vs_protocol_net_init(struct net *net) { + int i, ret; + static struct ip_vs_protocol *protos[] = { #ifdef CONFIG_IP_VS_PROTO_TCP - register_ip_vs_proto_netns(net, &ip_vs_protocol_tcp); + &ip_vs_protocol_tcp, #endif #ifdef CONFIG_IP_VS_PROTO_UDP - register_ip_vs_proto_netns(net, &ip_vs_protocol_udp); + &ip_vs_protocol_udp, #endif #ifdef CONFIG_IP_VS_PROTO_SCTP - register_ip_vs_proto_netns(net, &ip_vs_protocol_sctp); + &ip_vs_protocol_sctp, #endif #ifdef CONFIG_IP_VS_PROTO_AH - register_ip_vs_proto_netns(net, &ip_vs_protocol_ah); + &ip_vs_protocol_ah, #endif #ifdef CONFIG_IP_VS_PROTO_ESP - register_ip_vs_proto_netns(net, &ip_vs_protocol_esp); + &ip_vs_protocol_esp, #endif + }; + + for (i = 0; i < ARRAY_SIZE(protos); i++) { + ret = register_ip_vs_proto_netns(net, protos[i]); + if (ret < 0) + goto cleanup; + } return 0; + +cleanup: + ip_vs_protocol_net_cleanup(net); + return ret; } void __net_exit ip_vs_protocol_net_cleanup(struct net *net) -- 2.39.5