diff options
| author | Eric Dumazet <edumazet@google.com> | 2012-09-04 07:49:03 +0000 |
|---|---|---|
| committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2012-09-06 14:28:18 +0200 |
| commit | 0626af3139572610b56376580d11eb65d45d9dd7 (patch) | |
| tree | e1c4664b0afd65788e1508402a5ab60772c2dad0 /net | |
| parent | 5b716ac728bcc01b1f2a7ed6e437196602237c27 (diff) | |
netfilter: take care of timewait sockets
Sami Farin reported crashes in xt_LOG because it assumes skb->sk is a
full blown socket.
Since (41063e9 ipv4: Early TCP socket demux), we can have skb->sk
pointing to a timewait socket.
Same fix is needed in nfnetlink_log.
Diagnosed-by: Florian Westphal <fw@strlen.de>
Reported-by: Sami Farin <hvtaifwkbgefbaei@gmail.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Diffstat (limited to 'net')
| -rw-r--r-- | net/netfilter/nfnetlink_log.c | 14 | ||||
| -rw-r--r-- | net/netfilter/xt_LOG.c | 33 |
2 files changed, 25 insertions, 22 deletions
diff --git a/net/netfilter/nfnetlink_log.c b/net/netfilter/nfnetlink_log.c index 14e2f390314..5cfb5bedb2b 100644 --- a/net/netfilter/nfnetlink_log.c +++ b/net/netfilter/nfnetlink_log.c @@ -381,6 +381,7 @@ __build_packet_message(struct nfulnl_instance *inst, struct nlmsghdr *nlh; struct nfgenmsg *nfmsg; sk_buff_data_t old_tail = inst->skb->tail; + struct sock *sk; nlh = nlmsg_put(inst->skb, 0, 0, NFNL_SUBSYS_ULOG << 8 | NFULNL_MSG_PACKET, @@ -499,18 +500,19 @@ __build_packet_message(struct nfulnl_instance *inst, } /* UID */ - if (skb->sk) { - read_lock_bh(&skb->sk->sk_callback_lock); - if (skb->sk->sk_socket && skb->sk->sk_socket->file) { - struct file *file = skb->sk->sk_socket->file; + sk = skb->sk; + if (sk && sk->sk_state != TCP_TIME_WAIT) { + read_lock_bh(&sk->sk_callback_lock); + if (sk->sk_socket && sk->sk_socket->file) { + struct file *file = sk->sk_socket->file; __be32 uid = htonl(file->f_cred->fsuid); __be32 gid = htonl(file->f_cred->fsgid); - read_unlock_bh(&skb->sk->sk_callback_lock); + read_unlock_bh(&sk->sk_callback_lock); if (nla_put_be32(inst->skb, NFULA_UID, uid) || nla_put_be32(inst->skb, NFULA_GID, gid)) goto nla_put_failure; } else - read_unlock_bh(&skb->sk->sk_callback_lock); + read_unlock_bh(&sk->sk_callback_lock); } /* local sequence number */ diff --git a/net/netfilter/xt_LOG.c b/net/netfilter/xt_LOG.c index ff5f75fddb1..2a4f9693e79 100644 --- a/net/netfilter/xt_LOG.c +++ b/net/netfilter/xt_LOG.c @@ -145,6 +145,19 @@ static int dump_tcp_header(struct sbuff *m, const struct sk_buff *skb, return 0; } +static void dump_sk_uid_gid(struct sbuff *m, struct sock *sk) +{ + if (!sk || sk->sk_state == TCP_TIME_WAIT) + return; + + read_lock_bh(&sk->sk_callback_lock); + if (sk->sk_socket && sk->sk_socket->file) + sb_add(m, "UID=%u GID=%u ", + sk->sk_socket->file->f_cred->fsuid, + sk->sk_socket->file->f_cred->fsgid); + read_unlock_bh(&sk->sk_callback_lock); +} + /* One level of recursion won't kill us */ static void dump_ipv4_packet(struct sbuff *m, const struct nf_loginfo *info, @@ -361,14 +374,8 @@ static void dump_ipv4_packet(struct sbuff *m, } /* Max length: 15 "UID=4294967295 " */ - if ((logflags & XT_LOG_UID) && !iphoff && skb->sk) { - read_lock_bh(&skb->sk->sk_callback_lock); - if (skb->sk->sk_socket && skb->sk->sk_socket->file) - sb_add(m, "UID=%u GID=%u ", - skb->sk->sk_socket->file->f_cred->fsuid, - skb->sk->sk_socket->file->f_cred->fsgid); - read_unlock_bh(&skb->sk->sk_callback_lock); - } + if ((logflags & XT_LOG_UID) && !iphoff) + dump_sk_uid_gid(m, skb->sk); /* Max length: 16 "MARK=0xFFFFFFFF " */ if (!iphoff && skb->mark) @@ -717,14 +724,8 @@ static void dump_ipv6_packet(struct sbuff *m, } /* Max length: 15 "UID=4294967295 " */ - if ((logflags & XT_LOG_UID) && recurse && skb->sk) { - read_lock_bh(&skb->sk->sk_callback_lock); - if (skb->sk->sk_socket && skb->sk->sk_socket->file) - sb_add(m, "UID=%u GID=%u ", - skb->sk->sk_socket->file->f_cred->fsuid, - skb->sk->sk_socket->file->f_cred->fsgid); - read_unlock_bh(&skb->sk->sk_callback_lock); - } + if ((logflags & XT_LOG_UID) && recurse) + dump_sk_uid_gid(m, skb->sk); /* Max length: 16 "MARK=0xFFFFFFFF " */ if (!recurse && skb->mark) |