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| author | Xin Long <lucien.xin@gmail.com> | 2017-10-18 15:37:49 +0200 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2017-10-20 13:53:45 +0200 |
| commit | 1cc276cec9ec574d41cf47dfc0f51406b6f26ab4 (patch) | |
| tree | 71b86cf028499fe8d327f3a1b660fd3bb79264e0 /net/sctp/input.c | |
| parent | sctp: do not peel off an assoc from one netns to another one (diff) | |
| download | linux-1cc276cec9ec574d41cf47dfc0f51406b6f26ab4.tar.xz linux-1cc276cec9ec574d41cf47dfc0f51406b6f26ab4.zip | |
sctp: add the missing sock_owned_by_user check in sctp_icmp_redirect
Now sctp processes icmp redirect packet in sctp_icmp_redirect where
it calls sctp_transport_dst_check in which tp->dst can be released.
The problem is before calling sctp_transport_dst_check, it doesn't
check sock_owned_by_user, which means tp->dst could be freed while
a process is accessing it with owning the socket.
An use-after-free issue could be triggered by this.
This patch is to fix it by checking sock_owned_by_user before calling
sctp_transport_dst_check in sctp_icmp_redirect, so that it would not
release tp->dst if users still hold sock lock.
Besides, the same issue fixed in commit 45caeaa5ac0b ("dccp/tcp: fix
routing redirect race") on sctp also needs this check.
Fixes: 55be7a9c6074 ("ipv4: Add redirect support to all protocol icmp error handlers")
Reported-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to '')
| -rw-r--r-- | net/sctp/input.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/net/sctp/input.c b/net/sctp/input.c index 92a07141fd07..34f10e75f3b9 100644 --- a/net/sctp/input.c +++ b/net/sctp/input.c @@ -421,7 +421,7 @@ void sctp_icmp_redirect(struct sock *sk, struct sctp_transport *t, { struct dst_entry *dst; - if (!t) + if (sock_owned_by_user(sk) || !t) return; dst = sctp_transport_dst_check(t); if (dst) |