From ca84bd058daefef1d184dd0a7b6b43c67339e72c Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Sun, 19 Jul 2020 09:21:38 +0200 Subject: [PATCH] sctp: copy the optval from user space in sctp_setsockopt Prepare for for moving the copy_from_user from the individual sockopts to the main setsockopt helper. As of this commit the kopt variable is not used yet, but the following commits will start using it. Signed-off-by: Christoph Hellwig Signed-off-by: David S. Miller --- net/sctp/socket.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/net/sctp/socket.c b/net/sctp/socket.c index d57e1a002ffc..af1ebc8313d3 100644 --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -4677,6 +4677,7 @@ out: static int sctp_setsockopt(struct sock *sk, int level, int optname, char __user *optval, unsigned int optlen) { + void *kopt = NULL; int retval = 0; pr_debug("%s: sk:%p, optname:%d\n", __func__, sk, optname); @@ -4693,6 +4694,12 @@ static int sctp_setsockopt(struct sock *sk, int level, int optname, goto out_nounlock; } + if (optlen > 0) { + kopt = memdup_user(optval, optlen); + if (IS_ERR(kopt)) + return PTR_ERR(kopt); + } + lock_sock(sk); switch (optname) { @@ -4878,6 +4885,7 @@ static int sctp_setsockopt(struct sock *sk, int level, int optname, } release_sock(sk); + kfree(kopt); out_nounlock: return retval;