Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932607AbaBEVJ7 (ORCPT ); Wed, 5 Feb 2014 16:09:59 -0500 Received: from mail.windriver.com ([147.11.1.11]:54319 "EHLO mail.windriver.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754068AbaBEUEC (ORCPT ); Wed, 5 Feb 2014 15:04:02 -0500 From: Paul Gortmaker To: , CC: Eric Dumazet , Herbert Xu , "David S. Miller" , Ben Hutchings , Willy Tarreau , Paul Gortmaker Subject: [v2.6.34-stable 005/213] inet: add RCU protection to inet->opt Date: Wed, 5 Feb 2014 14:59:20 -0500 Message-ID: <1391630568-49251-6-git-send-email-paul.gortmaker@windriver.com> X-Mailer: git-send-email 1.8.5.2 In-Reply-To: <1391630568-49251-1-git-send-email-paul.gortmaker@windriver.com> References: <1391630568-49251-1-git-send-email-paul.gortmaker@windriver.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Eric Dumazet ------------------- This is a commit scheduled for the next v2.6.34 longterm release. http://git.kernel.org/?p=linux/kernel/git/paulg/longterm-queue-2.6.34.git If you see a problem with using this for longterm, please comment. ------------------- commit f6d8bd051c391c1c0458a30b2a7abcd939329259 upstream. We lack proper synchronization to manipulate inet->opt ip_options Problem is ip_make_skb() calls ip_setup_cork() and ip_setup_cork() possibly makes a copy of ipc->opt (struct ip_options), without any protection against another thread manipulating inet->opt. Another thread can change inet->opt pointer and free old one under us. Use RCU to protect inet->opt (changed to inet->inet_opt). Instead of handling atomic refcounts, just copy ip_options when necessary, to avoid cache line dirtying. We cant insert an rcu_head in struct ip_options since its included in skb->cb[], so this patch is large because I had to introduce a new ip_options_rcu structure. Signed-off-by: Eric Dumazet Cc: Herbert Xu Signed-off-by: David S. Miller [dannf/bwh: backported to Debian's 2.6.32] Signed-off-by: Ben Hutchings Signed-off-by: Willy Tarreau [PG: use 2.6.32 patch, since it is closer to 2.6.34 than original baseline; drop net/l2tp/l2tp_ip.c chunk as we don't have that file] Signed-off-by: Paul Gortmaker --- include/net/inet_sock.h | 14 +++-- include/net/ip.h | 11 ++-- net/dccp/ipv4.c | 15 +++--- net/dccp/ipv6.c | 2 +- net/ipv4/af_inet.c | 16 ++++-- net/ipv4/cipso_ipv4.c | 113 ++++++++++++++++++++++------------------ net/ipv4/icmp.c | 23 ++++---- net/ipv4/inet_connection_sock.c | 8 +-- net/ipv4/ip_options.c | 38 +++++++------- net/ipv4/ip_output.c | 50 +++++++++--------- net/ipv4/ip_sockglue.c | 33 ++++++++---- net/ipv4/raw.c | 19 +++++-- net/ipv4/syncookies.c | 4 +- net/ipv4/tcp_ipv4.c | 33 +++++++----- net/ipv4/udp.c | 21 ++++++-- net/ipv6/tcp_ipv6.c | 2 +- 16 files changed, 235 insertions(+), 167 deletions(-) diff --git a/include/net/inet_sock.h b/include/net/inet_sock.h index 83fd34437cf1..648000dd4b97 100644 --- a/include/net/inet_sock.h +++ b/include/net/inet_sock.h @@ -56,7 +56,15 @@ struct ip_options { unsigned char __data[0]; }; -#define optlength(opt) (sizeof(struct ip_options) + opt->optlen) +struct ip_options_rcu { + struct rcu_head rcu; + struct ip_options opt; +}; + +struct ip_options_data { + struct ip_options_rcu opt; + char data[40]; +}; struct inet_request_sock { struct request_sock req; @@ -77,7 +85,7 @@ struct inet_request_sock { acked : 1, no_srccheck: 1; kmemcheck_bitfield_end(flags); - struct ip_options *opt; + struct ip_options_rcu *opt; }; static inline struct inet_request_sock *inet_rsk(const struct request_sock *sk) @@ -125,7 +133,7 @@ struct inet_sock { __be16 inet_sport; __u16 inet_id; - struct ip_options *opt; + struct ip_options_rcu *inet_opt; __u8 tos; __u8 min_ttl; __u8 mc_ttl; diff --git a/include/net/ip.h b/include/net/ip.h index 503994a38ed1..ac9506e74c29 100644 --- a/include/net/ip.h +++ b/include/net/ip.h @@ -52,7 +52,7 @@ static inline unsigned int ip_hdrlen(const struct sk_buff *skb) struct ipcm_cookie { __be32 addr; int oif; - struct ip_options *opt; + struct ip_options_rcu *opt; union skb_shared_tx shtx; }; @@ -89,7 +89,7 @@ extern int igmp_mc_proc_init(void); extern int ip_build_and_send_pkt(struct sk_buff *skb, struct sock *sk, __be32 saddr, __be32 daddr, - struct ip_options *opt); + struct ip_options_rcu *opt); extern int ip_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev); extern int ip_local_deliver(struct sk_buff *skb); @@ -376,14 +376,15 @@ extern int ip_forward(struct sk_buff *skb); * Functions provided by ip_options.c */ -extern void ip_options_build(struct sk_buff *skb, struct ip_options *opt, __be32 daddr, struct rtable *rt, int is_frag); +extern void ip_options_build(struct sk_buff *skb, struct ip_options *opt, + __be32 daddr, struct rtable *rt, int is_frag); extern int ip_options_echo(struct ip_options *dopt, struct sk_buff *skb); extern void ip_options_fragment(struct sk_buff *skb); extern int ip_options_compile(struct net *net, struct ip_options *opt, struct sk_buff *skb); -extern int ip_options_get(struct net *net, struct ip_options **optp, +extern int ip_options_get(struct net *net, struct ip_options_rcu **optp, unsigned char *data, int optlen); -extern int ip_options_get_from_user(struct net *net, struct ip_options **optp, +extern int ip_options_get_from_user(struct net *net, struct ip_options_rcu **optp, unsigned char __user *data, int optlen); extern void ip_options_undo(struct ip_options * opt); extern void ip_forward_options(struct sk_buff *skb); diff --git a/net/dccp/ipv4.c b/net/dccp/ipv4.c index e072e018b068..d73f17ff95f6 100644 --- a/net/dccp/ipv4.c +++ b/net/dccp/ipv4.c @@ -48,6 +48,7 @@ int dccp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) __be32 daddr, nexthop; int tmp; int err; + struct ip_options_rcu *inet_opt; dp->dccps_role = DCCP_ROLE_CLIENT; @@ -58,10 +59,12 @@ int dccp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) return -EAFNOSUPPORT; nexthop = daddr = usin->sin_addr.s_addr; - if (inet->opt != NULL && inet->opt->srr) { + + inet_opt = inet->inet_opt; + if (inet_opt != NULL && inet_opt->opt.srr) { if (daddr == 0) return -EINVAL; - nexthop = inet->opt->faddr; + nexthop = inet_opt->opt.faddr; } tmp = ip_route_connect(&rt, nexthop, inet->inet_saddr, @@ -76,7 +79,7 @@ int dccp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) return -ENETUNREACH; } - if (inet->opt == NULL || !inet->opt->srr) + if (inet_opt == NULL || !inet_opt->opt.srr) daddr = rt->rt_dst; if (inet->inet_saddr == 0) @@ -87,8 +90,8 @@ int dccp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) inet->inet_daddr = daddr; inet_csk(sk)->icsk_ext_hdr_len = 0; - if (inet->opt != NULL) - inet_csk(sk)->icsk_ext_hdr_len = inet->opt->optlen; + if (inet_opt) + inet_csk(sk)->icsk_ext_hdr_len = inet_opt->opt.optlen; /* * Socket identity is still unknown (sport may be zero). * However we set state to DCCP_REQUESTING and not releasing socket @@ -402,7 +405,7 @@ struct sock *dccp_v4_request_recv_sock(struct sock *sk, struct sk_buff *skb, newinet->inet_daddr = ireq->rmt_addr; newinet->inet_rcv_saddr = ireq->loc_addr; newinet->inet_saddr = ireq->loc_addr; - newinet->opt = ireq->opt; + newinet->inet_opt = ireq->opt; ireq->opt = NULL; newinet->mc_index = inet_iif(skb); newinet->mc_ttl = ip_hdr(skb)->ttl; diff --git a/net/dccp/ipv6.c b/net/dccp/ipv6.c index fec7de6cfe6e..90f65e1dd4cf 100644 --- a/net/dccp/ipv6.c +++ b/net/dccp/ipv6.c @@ -600,7 +600,7 @@ static struct sock *dccp_v6_request_recv_sock(struct sock *sk, First: no IPv4 options. */ - newinet->opt = NULL; + newinet->inet_opt = NULL; /* Clone RX bits */ newnp->rxopt.all = np->rxopt.all; diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c index 8897b3c7d05a..4dd4aad58d93 100644 --- a/net/ipv4/af_inet.c +++ b/net/ipv4/af_inet.c @@ -153,7 +153,7 @@ void inet_sock_destruct(struct sock *sk) WARN_ON(sk->sk_wmem_queued); WARN_ON(sk->sk_forward_alloc); - kfree(inet->opt); + kfree(inet->inet_opt); dst_release(sk->sk_dst_cache); sk_refcnt_debug_dec(sk); } @@ -1069,9 +1069,11 @@ static int inet_sk_reselect_saddr(struct sock *sk) __be32 old_saddr = inet->inet_saddr; __be32 new_saddr; __be32 daddr = inet->inet_daddr; + struct ip_options_rcu *inet_opt; - if (inet->opt && inet->opt->srr) - daddr = inet->opt->faddr; + inet_opt = inet->inet_opt; + if (inet_opt && inet_opt->opt.srr) + daddr = inet_opt->opt.faddr; /* Query new route. */ err = ip_route_connect(&rt, daddr, 0, @@ -1113,6 +1115,7 @@ int inet_sk_rebuild_header(struct sock *sk) struct inet_sock *inet = inet_sk(sk); struct rtable *rt = (struct rtable *)__sk_dst_check(sk, 0); __be32 daddr; + struct ip_options_rcu *inet_opt; int err; /* Route is OK, nothing to do. */ @@ -1120,9 +1123,12 @@ int inet_sk_rebuild_header(struct sock *sk) return 0; /* Reroute. */ + rcu_read_lock(); + inet_opt = rcu_dereference(inet->inet_opt); daddr = inet->inet_daddr; - if (inet->opt && inet->opt->srr) - daddr = inet->opt->faddr; + if (inet_opt && inet_opt->opt.srr) + daddr = inet_opt->opt.faddr; + rcu_read_unlock(); { struct flowi fl = { .oif = sk->sk_bound_dev_if, diff --git a/net/ipv4/cipso_ipv4.c b/net/ipv4/cipso_ipv4.c index c97cd9ff697e..d5ef60963183 100644 --- a/net/ipv4/cipso_ipv4.c +++ b/net/ipv4/cipso_ipv4.c @@ -1859,6 +1859,11 @@ static int cipso_v4_genopt(unsigned char *buf, u32 buf_len, return CIPSO_V4_HDR_LEN + ret_val; } +static void opt_kfree_rcu(struct rcu_head *head) +{ + kfree(container_of(head, struct ip_options_rcu, rcu)); +} + /** * cipso_v4_sock_setattr - Add a CIPSO option to a socket * @sk: the socket @@ -1881,7 +1886,7 @@ int cipso_v4_sock_setattr(struct sock *sk, unsigned char *buf = NULL; u32 buf_len; u32 opt_len; - struct ip_options *opt = NULL; + struct ip_options_rcu *old, *opt = NULL; struct inet_sock *sk_inet; struct inet_connection_sock *sk_conn; @@ -1917,22 +1922,25 @@ int cipso_v4_sock_setattr(struct sock *sk, ret_val = -ENOMEM; goto socket_setattr_failure; } - memcpy(opt->__data, buf, buf_len); - opt->optlen = opt_len; - opt->cipso = sizeof(struct iphdr); + memcpy(opt->opt.__data, buf, buf_len); + opt->opt.optlen = opt_len; + opt->opt.cipso = sizeof(struct iphdr); kfree(buf); buf = NULL; sk_inet = inet_sk(sk); + + old = sk_inet->inet_opt; if (sk_inet->is_icsk) { sk_conn = inet_csk(sk); - if (sk_inet->opt) - sk_conn->icsk_ext_hdr_len -= sk_inet->opt->optlen; - sk_conn->icsk_ext_hdr_len += opt->optlen; + if (old) + sk_conn->icsk_ext_hdr_len -= old->opt.optlen; + sk_conn->icsk_ext_hdr_len += opt->opt.optlen; sk_conn->icsk_sync_mss(sk, sk_conn->icsk_pmtu_cookie); } - opt = xchg(&sk_inet->opt, opt); - kfree(opt); + rcu_assign_pointer(sk_inet->inet_opt, opt); + if (old) + call_rcu(&old->rcu, opt_kfree_rcu); return 0; @@ -1962,7 +1970,7 @@ int cipso_v4_req_setattr(struct request_sock *req, unsigned char *buf = NULL; u32 buf_len; u32 opt_len; - struct ip_options *opt = NULL; + struct ip_options_rcu *opt = NULL; struct inet_request_sock *req_inet; /* We allocate the maximum CIPSO option size here so we are probably @@ -1990,15 +1998,16 @@ int cipso_v4_req_setattr(struct request_sock *req, ret_val = -ENOMEM; goto req_setattr_failure; } - memcpy(opt->__data, buf, buf_len); - opt->optlen = opt_len; - opt->cipso = sizeof(struct iphdr); + memcpy(opt->opt.__data, buf, buf_len); + opt->opt.optlen = opt_len; + opt->opt.cipso = sizeof(struct iphdr); kfree(buf); buf = NULL; req_inet = inet_rsk(req); opt = xchg(&req_inet->opt, opt); - kfree(opt); + if (opt) + call_rcu(&opt->rcu, opt_kfree_rcu); return 0; @@ -2018,34 +2027,34 @@ req_setattr_failure: * values on failure. * */ -static int cipso_v4_delopt(struct ip_options **opt_ptr) +static int cipso_v4_delopt(struct ip_options_rcu **opt_ptr) { int hdr_delta = 0; - struct ip_options *opt = *opt_ptr; + struct ip_options_rcu *opt = *opt_ptr; - if (opt->srr || opt->rr || opt->ts || opt->router_alert) { + if (opt->opt.srr || opt->opt.rr || opt->opt.ts || opt->opt.router_alert) { u8 cipso_len; u8 cipso_off; unsigned char *cipso_ptr; int iter; int optlen_new; - cipso_off = opt->cipso - sizeof(struct iphdr); - cipso_ptr = &opt->__data[cipso_off]; + cipso_off = opt->opt.cipso - sizeof(struct iphdr); + cipso_ptr = &opt->opt.__data[cipso_off]; cipso_len = cipso_ptr[1]; - if (opt->srr > opt->cipso) - opt->srr -= cipso_len; - if (opt->rr > opt->cipso) - opt->rr -= cipso_len; - if (opt->ts > opt->cipso) - opt->ts -= cipso_len; - if (opt->router_alert > opt->cipso) - opt->router_alert -= cipso_len; - opt->cipso = 0; + if (opt->opt.srr > opt->opt.cipso) + opt->opt.srr -= cipso_len; + if (opt->opt.rr > opt->opt.cipso) + opt->opt.rr -= cipso_len; + if (opt->opt.ts > opt->opt.cipso) + opt->opt.ts -= cipso_len; + if (opt->opt.router_alert > opt->opt.cipso) + opt->opt.router_alert -= cipso_len; + opt->opt.cipso = 0; memmove(cipso_ptr, cipso_ptr + cipso_len, - opt->optlen - cipso_off - cipso_len); + opt->opt.optlen - cipso_off - cipso_len); /* determining the new total option length is tricky because of * the padding necessary, the only thing i can think to do at @@ -2054,21 +2063,21 @@ static int cipso_v4_delopt(struct ip_options **opt_ptr) * from there we can determine the new total option length */ iter = 0; optlen_new = 0; - while (iter < opt->optlen) - if (opt->__data[iter] != IPOPT_NOP) { - iter += opt->__data[iter + 1]; + while (iter < opt->opt.optlen) + if (opt->opt.__data[iter] != IPOPT_NOP) { + iter += opt->opt.__data[iter + 1]; optlen_new = iter; } else iter++; - hdr_delta = opt->optlen; - opt->optlen = (optlen_new + 3) & ~3; - hdr_delta -= opt->optlen; + hdr_delta = opt->opt.optlen; + opt->opt.optlen = (optlen_new + 3) & ~3; + hdr_delta -= opt->opt.optlen; } else { /* only the cipso option was present on the socket so we can * remove the entire option struct */ *opt_ptr = NULL; - hdr_delta = opt->optlen; - kfree(opt); + hdr_delta = opt->opt.optlen; + call_rcu(&opt->rcu, opt_kfree_rcu); } return hdr_delta; @@ -2085,15 +2094,15 @@ static int cipso_v4_delopt(struct ip_options **opt_ptr) void cipso_v4_sock_delattr(struct sock *sk) { int hdr_delta; - struct ip_options *opt; + struct ip_options_rcu *opt; struct inet_sock *sk_inet; sk_inet = inet_sk(sk); - opt = sk_inet->opt; - if (opt == NULL || opt->cipso == 0) + opt = sk_inet->inet_opt; + if (opt == NULL || opt->opt.cipso == 0) return; - hdr_delta = cipso_v4_delopt(&sk_inet->opt); + hdr_delta = cipso_v4_delopt(&sk_inet->inet_opt); if (sk_inet->is_icsk && hdr_delta > 0) { struct inet_connection_sock *sk_conn = inet_csk(sk); sk_conn->icsk_ext_hdr_len -= hdr_delta; @@ -2111,12 +2120,12 @@ void cipso_v4_sock_delattr(struct sock *sk) */ void cipso_v4_req_delattr(struct request_sock *req) { - struct ip_options *opt; + struct ip_options_rcu *opt; struct inet_request_sock *req_inet; req_inet = inet_rsk(req); opt = req_inet->opt; - if (opt == NULL || opt->cipso == 0) + if (opt == NULL || opt->opt.cipso == 0) return; cipso_v4_delopt(&req_inet->opt); @@ -2186,14 +2195,18 @@ getattr_return: */ int cipso_v4_sock_getattr(struct sock *sk, struct netlbl_lsm_secattr *secattr) { - struct ip_options *opt; + struct ip_options_rcu *opt; + int res = -ENOMSG; - opt = inet_sk(sk)->opt; - if (opt == NULL || opt->cipso == 0) - return -ENOMSG; - - return cipso_v4_getattr(opt->__data + opt->cipso - sizeof(struct iphdr), - secattr); + rcu_read_lock(); + opt = rcu_dereference(inet_sk(sk)->inet_opt); + if (opt && opt->opt.cipso) + res = cipso_v4_getattr(opt->opt.__data + + opt->opt.cipso - + sizeof(struct iphdr), + secattr); + rcu_read_unlock(); + return res; } /** diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c index ac4dec132735..4a5137a9e24c 100644 --- a/net/ipv4/icmp.c +++ b/net/ipv4/icmp.c @@ -108,8 +108,7 @@ struct icmp_bxm { __be32 times[3]; } data; int head_len; - struct ip_options replyopts; - unsigned char optbuf[40]; + struct ip_options_data replyopts; }; /* An array of errno for error messages from dest unreach. */ @@ -363,7 +362,7 @@ static void icmp_reply(struct icmp_bxm *icmp_param, struct sk_buff *skb) struct inet_sock *inet; __be32 daddr; - if (ip_options_echo(&icmp_param->replyopts, skb)) + if (ip_options_echo(&icmp_param->replyopts.opt.opt, skb)) return; sk = icmp_xmit_lock(net); @@ -377,10 +376,10 @@ static void icmp_reply(struct icmp_bxm *icmp_param, struct sk_buff *skb) daddr = ipc.addr = rt->rt_src; ipc.opt = NULL; ipc.shtx.flags = 0; - if (icmp_param->replyopts.optlen) { - ipc.opt = &icmp_param->replyopts; - if (ipc.opt->srr) - daddr = icmp_param->replyopts.faddr; + if (icmp_param->replyopts.opt.opt.optlen) { + ipc.opt = &icmp_param->replyopts.opt; + if (ipc.opt->opt.srr) + daddr = icmp_param->replyopts.opt.opt.faddr; } { struct flowi fl = { .nl_u = { .ip4_u = @@ -518,7 +517,7 @@ void icmp_send(struct sk_buff *skb_in, int type, int code, __be32 info) IPTOS_PREC_INTERNETCONTROL) : iph->tos; - if (ip_options_echo(&icmp_param.replyopts, skb_in)) + if (ip_options_echo(&icmp_param.replyopts.opt.opt, skb_in)) goto out_unlock; @@ -534,15 +533,15 @@ void icmp_send(struct sk_buff *skb_in, int type, int code, __be32 info) icmp_param.offset = skb_network_offset(skb_in); inet_sk(sk)->tos = tos; ipc.addr = iph->saddr; - ipc.opt = &icmp_param.replyopts; + ipc.opt = &icmp_param.replyopts.opt; ipc.shtx.flags = 0; { struct flowi fl = { .nl_u = { .ip4_u = { - .daddr = icmp_param.replyopts.srr ? - icmp_param.replyopts.faddr : + .daddr = icmp_param.replyopts.opt.opt.srr ? + icmp_param.replyopts.opt.opt.faddr : iph->saddr, .saddr = saddr, .tos = RT_TOS(tos) @@ -631,7 +630,7 @@ route_done: room = dst_mtu(&rt->u.dst); if (room > 576) room = 576; - room -= sizeof(struct iphdr) + icmp_param.replyopts.optlen; + room -= sizeof(struct iphdr) + icmp_param.replyopts.opt.opt.optlen; room -= sizeof(struct icmphdr); icmp_param.data_len = skb_in->len - icmp_param.offset; diff --git a/net/ipv4/inet_connection_sock.c b/net/ipv4/inet_connection_sock.c index 8da6429269dd..9f57d0f75631 100644 --- a/net/ipv4/inet_connection_sock.c +++ b/net/ipv4/inet_connection_sock.c @@ -356,12 +356,12 @@ struct dst_entry *inet_csk_route_req(struct sock *sk, { struct rtable *rt; const struct inet_request_sock *ireq = inet_rsk(req); - struct ip_options *opt = inet_rsk(req)->opt; + struct ip_options_rcu *opt = inet_rsk(req)->opt; struct flowi fl = { .oif = sk->sk_bound_dev_if, .mark = sk->sk_mark, .nl_u = { .ip4_u = - { .daddr = ((opt && opt->srr) ? - opt->faddr : + { .daddr = ((opt && opt->opt.srr) ? + opt->opt.faddr : ireq->rmt_addr), .saddr = ireq->loc_addr, .tos = RT_CONN_FLAGS(sk) } }, @@ -375,7 +375,7 @@ struct dst_entry *inet_csk_route_req(struct sock *sk, security_req_classify_flow(req, &fl); if (ip_route_output_flow(net, &rt, &fl, sk, 0)) goto no_route; - if (opt && opt->is_strictroute && rt->rt_dst != rt->rt_gateway) + if (opt && opt->opt.is_strictroute && rt->rt_dst != rt->rt_gateway) goto route_err; return &rt->u.dst; diff --git a/net/ipv4/ip_options.c b/net/ipv4/ip_options.c index 4c09a31fd140..f4281aad1df0 100644 --- a/net/ipv4/ip_options.c +++ b/net/ipv4/ip_options.c @@ -36,7 +36,7 @@ * saddr is address of outgoing interface. */ -void ip_options_build(struct sk_buff * skb, struct ip_options * opt, +void ip_options_build(struct sk_buff *skb, struct ip_options *opt, __be32 daddr, struct rtable *rt, int is_frag) { unsigned char *iph = skb_network_header(skb); @@ -83,9 +83,9 @@ void ip_options_build(struct sk_buff * skb, struct ip_options * opt, * NOTE: dopt cannot point to skb. */ -int ip_options_echo(struct ip_options * dopt, struct sk_buff * skb) +int ip_options_echo(struct ip_options *dopt, struct sk_buff *skb) { - struct ip_options *sopt; + const struct ip_options *sopt; unsigned char *sptr, *dptr; int soffset, doffset; int optlen; @@ -95,10 +95,8 @@ int ip_options_echo(struct ip_options * dopt, struct sk_buff * skb) sopt = &(IPCB(skb)->opt); - if (sopt->optlen == 0) { - dopt->optlen = 0; + if (sopt->optlen == 0) return 0; - } sptr = skb_network_header(skb); dptr = dopt->__data; @@ -157,7 +155,7 @@ int ip_options_echo(struct ip_options * dopt, struct sk_buff * skb) dopt->optlen += optlen; } if (sopt->srr) { - unsigned char * start = sptr+sopt->srr; + unsigned char *start = sptr+sopt->srr; __be32 faddr; optlen = start[1]; @@ -500,19 +498,19 @@ void ip_options_undo(struct ip_options * opt) } } -static struct ip_options *ip_options_get_alloc(const int optlen) +static struct ip_options_rcu *ip_options_get_alloc(const int optlen) { - return kzalloc(sizeof(struct ip_options) + ((optlen + 3) & ~3), + return kzalloc(sizeof(struct ip_options_rcu) + ((optlen + 3) & ~3), GFP_KERNEL); } -static int ip_options_get_finish(struct net *net, struct ip_options **optp, - struct ip_options *opt, int optlen) +static int ip_options_get_finish(struct net *net, struct ip_options_rcu **optp, + struct ip_options_rcu *opt, int optlen) { while (optlen & 3) - opt->__data[optlen++] = IPOPT_END; - opt->optlen = optlen; - if (optlen && ip_options_compile(net, opt, NULL)) { + opt->opt.__data[optlen++] = IPOPT_END; + opt->opt.optlen = optlen; + if (optlen && ip_options_compile(net, &opt->opt, NULL)) { kfree(opt); return -EINVAL; } @@ -521,29 +519,29 @@ static int ip_options_get_finish(struct net *net, struct ip_options **optp, return 0; } -int ip_options_get_from_user(struct net *net, struct ip_options **optp, +int ip_options_get_from_user(struct net *net, struct ip_options_rcu **optp, unsigned char __user *data, int optlen) { - struct ip_options *opt = ip_options_get_alloc(optlen); + struct ip_options_rcu *opt = ip_options_get_alloc(optlen); if (!opt) return -ENOMEM; - if (optlen && copy_from_user(opt->__data, data, optlen)) { + if (optlen && copy_from_user(opt->opt.__data, data, optlen)) { kfree(opt); return -EFAULT; } return ip_options_get_finish(net, optp, opt, optlen); } -int ip_options_get(struct net *net, struct ip_options **optp, +int ip_options_get(struct net *net, struct ip_options_rcu **optp, unsigned char *data, int optlen) { - struct ip_options *opt = ip_options_get_alloc(optlen); + struct ip_options_rcu *opt = ip_options_get_alloc(optlen); if (!opt) return -ENOMEM; if (optlen) - memcpy(opt->__data, data, optlen); + memcpy(opt->opt.__data, data, optlen); return ip_options_get_finish(net, optp, opt, optlen); } diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c index d52fe4bd573f..e669da63be31 100644 --- a/net/ipv4/ip_output.c +++ b/net/ipv4/ip_output.c @@ -138,14 +138,14 @@ static inline int ip_select_ttl(struct inet_sock *inet, struct dst_entry *dst) * */ int ip_build_and_send_pkt(struct sk_buff *skb, struct sock *sk, - __be32 saddr, __be32 daddr, struct ip_options *opt) + __be32 saddr, __be32 daddr, struct ip_options_rcu *opt) { struct inet_sock *inet = inet_sk(sk); struct rtable *rt = skb_rtable(skb); struct iphdr *iph; /* Build the IP header. */ - skb_push(skb, sizeof(struct iphdr) + (opt ? opt->optlen : 0)); + skb_push(skb, sizeof(struct iphdr) + (opt ? opt->opt.optlen : 0)); skb_reset_network_header(skb); iph = ip_hdr(skb); iph->version = 4; @@ -161,9 +161,9 @@ int ip_build_and_send_pkt(struct sk_buff *skb, struct sock *sk, iph->protocol = sk->sk_protocol; ip_select_ident(iph, &rt->u.dst, sk); - if (opt && opt->optlen) { - iph->ihl += opt->optlen>>2; - ip_options_build(skb, opt, daddr, rt, 0); + if (opt && opt->opt.optlen) { + iph->ihl += opt->opt.optlen>>2; + ip_options_build(skb, &opt->opt, daddr, rt, 0); } skb->priority = sk->sk_priority; @@ -315,9 +315,10 @@ int ip_queue_xmit(struct sk_buff *skb, int ipfragok) { struct sock *sk = skb->sk; struct inet_sock *inet = inet_sk(sk); - struct ip_options *opt = inet->opt; + struct ip_options_rcu *inet_opt = NULL; struct rtable *rt; struct iphdr *iph; + int res; /* Skip all of this if the packet is already routed, * f.e. by something like SCTP. @@ -328,13 +329,15 @@ int ip_queue_xmit(struct sk_buff *skb, int ipfragok) /* Make sure we can route this packet. */ rt = (struct rtable *)__sk_dst_check(sk, 0); + rcu_read_lock(); + inet_opt = rcu_dereference(inet->inet_opt); if (rt == NULL) { __be32 daddr; /* Use correct destination address if we have options. */ daddr = inet->inet_daddr; - if(opt && opt->srr) - daddr = opt->faddr; + if (inet_opt && inet_opt->opt.srr) + daddr = inet_opt->opt.faddr; { struct flowi fl = { .oif = sk->sk_bound_dev_if, @@ -362,11 +365,11 @@ int ip_queue_xmit(struct sk_buff *skb, int ipfragok) skb_dst_set(skb, dst_clone(&rt->u.dst)); packet_routed: - if (opt && opt->is_strictroute && rt->rt_dst != rt->rt_gateway) + if (inet_opt && inet_opt->opt.is_strictroute && rt->rt_dst != rt->rt_gateway) goto no_route; /* OK, we know where to send it, allocate and build IP header. */ - skb_push(skb, sizeof(struct iphdr) + (opt ? opt->optlen : 0)); + skb_push(skb, sizeof(struct iphdr) + (inet_opt ? inet_opt->opt.optlen : 0)); skb_reset_network_header(skb); iph = ip_hdr(skb); *((__be16 *)iph) = htons((4 << 12) | (5 << 8) | (inet->tos & 0xff)); @@ -380,9 +383,9 @@ packet_routed: iph->daddr = rt->rt_dst; /* Transport layer set skb->h.foo itself. */ - if (opt && opt->optlen) { - iph->ihl += opt->optlen >> 2; - ip_options_build(skb, opt, inet->inet_daddr, rt, 0); + if (inet_opt && inet_opt->opt.optlen) { + iph->ihl += inet_opt->opt.optlen >> 2; + ip_options_build(skb, &inet_opt->opt, inet->inet_daddr, rt, 0); } ip_select_ident_more(iph, &rt->u.dst, sk, @@ -390,10 +393,12 @@ packet_routed: skb->priority = sk->sk_priority; skb->mark = sk->sk_mark; - - return ip_local_out(skb); + res = ip_local_out(skb); + rcu_read_unlock(); + return res; no_route: + rcu_read_unlock(); IP_INC_STATS(sock_net(sk), IPSTATS_MIB_OUTNOROUTES); kfree_skb(skb); return -EHOSTUNREACH; @@ -812,7 +817,7 @@ int ip_append_data(struct sock *sk, /* * setup for corking. */ - opt = ipc->opt; + opt = ipc->opt ? &ipc->opt->opt : NULL; if (opt) { if (inet->cork.opt == NULL) { inet->cork.opt = kmalloc(sizeof(struct ip_options) + 40, sk->sk_allocation); @@ -1371,26 +1376,23 @@ void ip_send_reply(struct sock *sk, struct sk_buff *skb, struct ip_reply_arg *ar unsigned int len) { struct inet_sock *inet = inet_sk(sk); - struct { - struct ip_options opt; - char data[40]; - } replyopts; + struct ip_options_data replyopts; struct ipcm_cookie ipc; __be32 daddr; struct rtable *rt = skb_rtable(skb); - if (ip_options_echo(&replyopts.opt, skb)) + if (ip_options_echo(&replyopts.opt.opt, skb)) return; daddr = ipc.addr = rt->rt_src; ipc.opt = NULL; ipc.shtx.flags = 0; - if (replyopts.opt.optlen) { + if (replyopts.opt.opt.optlen) { ipc.opt = &replyopts.opt; - if (ipc.opt->srr) - daddr = replyopts.opt.faddr; + if (replyopts.opt.opt.srr) + daddr = replyopts.opt.opt.faddr; } { diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c index 1e64dabbd232..e4256fe59a30 100644 --- a/net/ipv4/ip_sockglue.c +++ b/net/ipv4/ip_sockglue.c @@ -435,6 +435,11 @@ out: } +static void opt_kfree_rcu(struct rcu_head *head) +{ + kfree(container_of(head, struct ip_options_rcu, rcu)); +} + /* * Socket option code for IP. This is the end of the line after any * TCP,UDP etc options on an IP socket. @@ -481,13 +486,15 @@ static int do_ip_setsockopt(struct sock *sk, int level, switch (optname) { case IP_OPTIONS: { - struct ip_options *opt = NULL; + struct ip_options_rcu *old, *opt = NULL; + if (optlen > 40) goto e_inval; err = ip_options_get_from_user(sock_net(sk), &opt, optval, optlen); if (err) break; + old = inet->inet_opt; if (inet->is_icsk) { struct inet_connection_sock *icsk = inet_csk(sk); #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) @@ -496,17 +503,18 @@ static int do_ip_setsockopt(struct sock *sk, int level, (TCPF_LISTEN | TCPF_CLOSE)) && inet->inet_daddr != LOOPBACK4_IPV6)) { #endif - if (inet->opt) - icsk->icsk_ext_hdr_len -= inet->opt->optlen; + if (old) + icsk->icsk_ext_hdr_len -= old->opt.optlen; if (opt) - icsk->icsk_ext_hdr_len += opt->optlen; + icsk->icsk_ext_hdr_len += opt->opt.optlen; icsk->icsk_sync_mss(sk, icsk->icsk_pmtu_cookie); #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) } #endif } - opt = xchg(&inet->opt, opt); - kfree(opt); + rcu_assign_pointer(inet->inet_opt, opt); + if (old) + call_rcu(&old->rcu, opt_kfree_rcu); break; } case IP_PKTINFO: @@ -1042,12 +1050,15 @@ static int do_ip_getsockopt(struct sock *sk, int level, int optname, case IP_OPTIONS: { unsigned char optbuf[sizeof(struct ip_options)+40]; - struct ip_options * opt = (struct ip_options *)optbuf; + struct ip_options *opt = (struct ip_options *)optbuf; + struct ip_options_rcu *inet_opt; + + inet_opt = inet->inet_opt; opt->optlen = 0; - if (inet->opt) - memcpy(optbuf, inet->opt, - sizeof(struct ip_options)+ - inet->opt->optlen); + if (inet_opt) + memcpy(optbuf, &inet_opt->opt, + sizeof(struct ip_options) + + inet_opt->opt.optlen); release_sock(sk); if (opt->optlen == 0) diff --git a/net/ipv4/raw.c b/net/ipv4/raw.c index cc6f097fbd5f..d5f57acd6f4b 100644 --- a/net/ipv4/raw.c +++ b/net/ipv4/raw.c @@ -457,6 +457,7 @@ static int raw_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, __be32 saddr; u8 tos; int err; + struct ip_options_data opt_copy; err = -EMSGSIZE; if (len > 0xFFFF) @@ -517,8 +518,18 @@ static int raw_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, saddr = ipc.addr; ipc.addr = daddr; - if (!ipc.opt) - ipc.opt = inet->opt; + if (!ipc.opt) { + struct ip_options_rcu *inet_opt; + + rcu_read_lock(); + inet_opt = rcu_dereference(inet->inet_opt); + if (inet_opt) { + memcpy(&opt_copy, inet_opt, + sizeof(*inet_opt) + inet_opt->opt.optlen); + ipc.opt = &opt_copy.opt; + } + rcu_read_unlock(); + } if (ipc.opt) { err = -EINVAL; @@ -527,10 +538,10 @@ static int raw_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, */ if (inet->hdrincl) goto done; - if (ipc.opt->srr) { + if (ipc.opt->opt.srr) { if (!daddr) goto done; - daddr = ipc.opt->faddr; + daddr = ipc.opt->opt.faddr; } } tos = RT_CONN_FLAGS(sk); diff --git a/net/ipv4/syncookies.c b/net/ipv4/syncookies.c index 9f6b22206c52..95ac6d7e0f42 100644 --- a/net/ipv4/syncookies.c +++ b/net/ipv4/syncookies.c @@ -310,10 +310,10 @@ struct sock *cookie_v4_check(struct sock *sk, struct sk_buff *skb, * the ACK carries the same options again (see RFC1122 4.2.3.8) */ if (opt && opt->optlen) { - int opt_size = sizeof(struct ip_options) + opt->optlen; + int opt_size = sizeof(struct ip_options_rcu) + opt->optlen; ireq->opt = kmalloc(opt_size, GFP_ATOMIC); - if (ireq->opt != NULL && ip_options_echo(ireq->opt, skb)) { + if (ireq->opt != NULL && ip_options_echo(&ireq->opt->opt, skb)) { kfree(ireq->opt); ireq->opt = NULL; } diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index ab7165565d23..8a0bff623731 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -153,6 +153,7 @@ int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) __be32 daddr, nexthop; int tmp; int err; + struct ip_options_rcu *inet_opt; if (addr_len < sizeof(struct sockaddr_in)) return -EINVAL; @@ -161,10 +162,11 @@ int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) return -EAFNOSUPPORT; nexthop = daddr = usin->sin_addr.s_addr; - if (inet->opt && inet->opt->srr) { + inet_opt = inet->inet_opt; + if (inet_opt && inet_opt->opt.srr) { if (!daddr) return -EINVAL; - nexthop = inet->opt->faddr; + nexthop = inet_opt->opt.faddr; } tmp = ip_route_connect(&rt, nexthop, inet->inet_saddr, @@ -182,7 +184,7 @@ int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) return -ENETUNREACH; } - if (!inet->opt || !inet->opt->srr) + if (!inet_opt || !inet_opt->opt.srr) daddr = rt->rt_dst; if (!inet->inet_saddr) @@ -216,8 +218,8 @@ int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) inet->inet_daddr = daddr; inet_csk(sk)->icsk_ext_hdr_len = 0; - if (inet->opt) - inet_csk(sk)->icsk_ext_hdr_len = inet->opt->optlen; + if (inet_opt) + inet_csk(sk)->icsk_ext_hdr_len = inet_opt->opt.optlen; tp->rx_opt.mss_clamp = TCP_MSS_DEFAULT; @@ -812,17 +814,18 @@ static void syn_flood_warning(struct sk_buff *skb) /* * Save and compile IPv4 options into the request_sock if needed. */ -static struct ip_options *tcp_v4_save_options(struct sock *sk, - struct sk_buff *skb) +static struct ip_options_rcu *tcp_v4_save_options(struct sock *sk, + struct sk_buff *skb) { - struct ip_options *opt = &(IPCB(skb)->opt); - struct ip_options *dopt = NULL; + const struct ip_options *opt = &(IPCB(skb)->opt); + struct ip_options_rcu *dopt = NULL; if (opt && opt->optlen) { - int opt_size = optlength(opt); + int opt_size = sizeof(*dopt) + opt->optlen; + dopt = kmalloc(opt_size, GFP_ATOMIC); if (dopt) { - if (ip_options_echo(dopt, skb)) { + if (ip_options_echo(&dopt->opt, skb)) { kfree(dopt); dopt = NULL; } @@ -1412,6 +1415,7 @@ struct sock *tcp_v4_syn_recv_sock(struct sock *sk, struct sk_buff *skb, #ifdef CONFIG_TCP_MD5SIG struct tcp_md5sig_key *key; #endif + struct ip_options_rcu *inet_opt; if (sk_acceptq_is_full(sk)) goto exit_overflow; @@ -1432,13 +1436,14 @@ struct sock *tcp_v4_syn_recv_sock(struct sock *sk, struct sk_buff *skb, newinet->inet_daddr = ireq->rmt_addr; newinet->inet_rcv_saddr = ireq->loc_addr; newinet->inet_saddr = ireq->loc_addr; - newinet->opt = ireq->opt; + inet_opt = ireq->opt; + rcu_assign_pointer(newinet->inet_opt, inet_opt); ireq->opt = NULL; newinet->mc_index = inet_iif(skb); newinet->mc_ttl = ip_hdr(skb)->ttl; inet_csk(newsk)->icsk_ext_hdr_len = 0; - if (newinet->opt) - inet_csk(newsk)->icsk_ext_hdr_len = newinet->opt->optlen; + if (inet_opt) + inet_csk(newsk)->icsk_ext_hdr_len = inet_opt->opt.optlen; newinet->inet_id = newtp->write_seq ^ jiffies; tcp_mtup_init(newsk); diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index 7932dc68c669..7f0a1ae0544b 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -784,6 +784,7 @@ int udp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, int err, is_udplite = IS_UDPLITE(sk); int corkreq = up->corkflag || msg->msg_flags&MSG_MORE; int (*getfrag)(void *, char *, int, int, int, struct sk_buff *); + struct ip_options_data opt_copy; if (len > 0xFFFF) return -EMSGSIZE; @@ -855,22 +856,32 @@ int udp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, free = 1; connected = 0; } - if (!ipc.opt) - ipc.opt = inet->opt; + if (!ipc.opt) { + struct ip_options_rcu *inet_opt; + + rcu_read_lock(); + inet_opt = rcu_dereference(inet->inet_opt); + if (inet_opt) { + memcpy(&opt_copy, inet_opt, + sizeof(*inet_opt) + inet_opt->opt.optlen); + ipc.opt = &opt_copy.opt; + } + rcu_read_unlock(); + } saddr = ipc.addr; ipc.addr = faddr = daddr; - if (ipc.opt && ipc.opt->srr) { + if (ipc.opt && ipc.opt->opt.srr) { if (!daddr) return -EINVAL; - faddr = ipc.opt->faddr; + faddr = ipc.opt->opt.faddr; connected = 0; } tos = RT_TOS(inet->tos); if (sock_flag(sk, SOCK_LOCALROUTE) || (msg->msg_flags & MSG_DONTROUTE) || - (ipc.opt && ipc.opt->is_strictroute)) { + (ipc.opt && ipc.opt->opt.is_strictroute)) { tos |= RTO_ONLINK; connected = 0; } diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index d854453b4daa..138a2db58bf8 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -1446,7 +1446,7 @@ static struct sock * tcp_v6_syn_recv_sock(struct sock *sk, struct sk_buff *skb, First: no IPv4 options. */ - newinet->opt = NULL; + newinet->inet_opt = NULL; newnp->ipv6_fl_list = NULL; /* Clone RX bits */ -- 1.8.5.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/