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author | Eric Dumazet <edumazet@google.com> | 2015-12-09 07:25:06 -0800 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2016-01-22 20:54:13 -0800 |
commit | 683f40ec958e669b0d376a0d83c0213783ee7f99 (patch) | |
tree | 5209b0c0c6402a2806f44a7016f2445098410dc9 | |
parent | dbc2d32fe4c0bb6ab3028ad986c42577ea059b6e (diff) | |
download | lwn-683f40ec958e669b0d376a0d83c0213783ee7f99.tar.gz lwn-683f40ec958e669b0d376a0d83c0213783ee7f99.zip |
ipv6: sctp: clone options to avoid use after free
[ Upstream commit 9470e24f35ab81574da54e69df90c1eb4a96b43f ]
SCTP is lacking proper np->opt cloning at accept() time.
TCP and DCCP use ipv6_dup_options() helper, do the same
in SCTP.
We might later factorize this code in a common helper to avoid
future mistakes.
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r-- | net/sctp/ipv6.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/net/sctp/ipv6.c b/net/sctp/ipv6.c index 0e4198ee2370..3267a5cbb3e8 100644 --- a/net/sctp/ipv6.c +++ b/net/sctp/ipv6.c @@ -634,6 +634,7 @@ static struct sock *sctp_v6_create_accept_sk(struct sock *sk, struct sock *newsk; struct ipv6_pinfo *newnp, *np = inet6_sk(sk); struct sctp6_sock *newsctp6sk; + struct ipv6_txoptions *opt; newsk = sk_alloc(sock_net(sk), PF_INET6, GFP_KERNEL, sk->sk_prot); if (!newsk) @@ -653,6 +654,13 @@ static struct sock *sctp_v6_create_accept_sk(struct sock *sk, memcpy(newnp, np, sizeof(struct ipv6_pinfo)); + rcu_read_lock(); + opt = rcu_dereference(np->opt); + if (opt) + opt = ipv6_dup_options(newsk, opt); + RCU_INIT_POINTER(newnp->opt, opt); + rcu_read_unlock(); + /* Initialize sk's sport, dport, rcv_saddr and daddr for getsockname() * and getpeername(). */ |