[PATCH 24/26] net/tcp: switch do_tcp_setsockopt to sockptr_t

From: Christoph Hellwig <hch@lst.de>
To: "David S. Miller" <davem@davemloft.net>,
	Jakub Kicinski <kuba@kernel.org>,
	Alexei Starovoitov <ast@kernel.org>,
	Daniel Borkmann <daniel@iogearbox.net>,
	Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>,
	Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>,
	Eric Dumazet <edumazet@google.com>
Cc: linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org,
	netdev@vger.kernel.org, bpf@vger.kernel.org,
	netfilter-devel@vger.kernel.org, coreteam@netfilter.org,
	linux-sctp@vger.kernel.org, linux-hams@vger.kernel.org,
	linux-bluetooth@vger.kernel.org,
	bridge@lists.linux-foundation.org, linux-can@vger.kernel.org,
	dccp@vger.kernel.org, linux-decnet-user@lists.sourceforge.net,
	linux-wpan@vger.kernel.org, linux-s390@vger.kernel.org,
	mptcp@lists.01.org, lvs-devel@vger.kernel.org,
	rds-devel@oss.oracle.com, linux-afs@lists.infradead.org,
	tipc-discussion@lists.sourceforge.net, linux-x25@vger.kernel.org
Subject: [PATCH 24/26] net/tcp: switch do_tcp_setsockopt to sockptr_t
Date: Thu, 23 Jul 2020 08:09:06 +0200
Message-ID: <20200723060908.50081-25-hch@lst.de> (raw)
In-Reply-To: <20200723060908.50081-1-hch@lst.de>

Pass a sockptr_t to prepare for set_fs-less handling of the kernel
pointer from bpf-cgroup.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 net/ipv4/tcp.c | 34 ++++++++++++++++------------------
 1 file changed, 16 insertions(+), 18 deletions(-)

diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 49bf15c27deac7..71cbc61c335f71 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -2764,7 +2764,7 @@ static inline bool tcp_can_repair_sock(const struct sock *sk)
 		(sk->sk_state != TCP_LISTEN);
 }
 
-static int tcp_repair_set_window(struct tcp_sock *tp, char __user *optbuf, int len)
+static int tcp_repair_set_window(struct tcp_sock *tp, sockptr_t optbuf, int len)
 {
 	struct tcp_repair_window opt;
 
@@ -2774,7 +2774,7 @@ static int tcp_repair_set_window(struct tcp_sock *tp, char __user *optbuf, int l
 	if (len != sizeof(opt))
 		return -EINVAL;
 
-	if (copy_from_user(&opt, optbuf, sizeof(opt)))
+	if (copy_from_sockptr(&opt, optbuf, sizeof(opt)))
 		return -EFAULT;
 
 	if (opt.max_window < opt.snd_wnd)
@@ -2796,17 +2796,17 @@ static int tcp_repair_set_window(struct tcp_sock *tp, char __user *optbuf, int l
 	return 0;
 }
 
-static int tcp_repair_options_est(struct sock *sk,
-		struct tcp_repair_opt __user *optbuf, unsigned int len)
+static int tcp_repair_options_est(struct sock *sk, sockptr_t optbuf,
+		unsigned int len)
 {
 	struct tcp_sock *tp = tcp_sk(sk);
 	struct tcp_repair_opt opt;
 
 	while (len >= sizeof(opt)) {
-		if (copy_from_user(&opt, optbuf, sizeof(opt)))
+		if (copy_from_sockptr(&opt, optbuf, sizeof(opt)))
 			return -EFAULT;
 
-		optbuf++;
+		sockptr_advance(optbuf, sizeof(opt));
 		len -= sizeof(opt);
 
 		switch (opt.opt_code) {
@@ -3020,8 +3020,8 @@ EXPORT_SYMBOL(tcp_sock_set_keepcnt);
 /*
  *	Socket option code for TCP.
  */
-static int do_tcp_setsockopt(struct sock *sk, int level,
-		int optname, char __user *optval, unsigned int optlen)
+static int do_tcp_setsockopt(struct sock *sk, int level, int optname,
+		sockptr_t optval, unsigned int optlen)
 {
 	struct tcp_sock *tp = tcp_sk(sk);
 	struct inet_connection_sock *icsk = inet_csk(sk);
@@ -3037,7 +3037,7 @@ static int do_tcp_setsockopt(struct sock *sk, int level,
 		if (optlen < 1)
 			return -EINVAL;
 
-		val = strncpy_from_user(name, optval,
+		val = strncpy_from_sockptr(name, optval,
 					min_t(long, TCP_CA_NAME_MAX-1, optlen));
 		if (val < 0)
 			return -EFAULT;
@@ -3056,7 +3056,7 @@ static int do_tcp_setsockopt(struct sock *sk, int level,
 		if (optlen < 1)
 			return -EINVAL;
 
-		val = strncpy_from_user(name, optval,
+		val = strncpy_from_sockptr(name, optval,
 					min_t(long, TCP_ULP_NAME_MAX - 1,
 					      optlen));
 		if (val < 0)
@@ -3079,7 +3079,7 @@ static int do_tcp_setsockopt(struct sock *sk, int level,
 		    optlen != TCP_FASTOPEN_KEY_BUF_LENGTH)
 			return -EINVAL;
 
-		if (copy_from_user(key, optval, optlen))
+		if (copy_from_sockptr(key, optval, optlen))
 			return -EFAULT;
 
 		if (optlen == TCP_FASTOPEN_KEY_BUF_LENGTH)
@@ -3095,7 +3095,7 @@ static int do_tcp_setsockopt(struct sock *sk, int level,
 	if (optlen < sizeof(int))
 		return -EINVAL;
 
-	if (get_user(val, (int __user *)optval))
+	if (copy_from_sockptr(&val, optval, sizeof(val)))
 		return -EFAULT;
 
 	lock_sock(sk);
@@ -3174,9 +3174,7 @@ static int do_tcp_setsockopt(struct sock *sk, int level,
 		if (!tp->repair)
 			err = -EINVAL;
 		else if (sk->sk_state == TCP_ESTABLISHED)
-			err = tcp_repair_options_est(sk,
-					(struct tcp_repair_opt __user *)optval,
-					optlen);
+			err = tcp_repair_options_est(sk, optval, optlen);
 		else
 			err = -EPERM;
 		break;
@@ -3249,8 +3247,7 @@ static int do_tcp_setsockopt(struct sock *sk, int level,
 #ifdef CONFIG_TCP_MD5SIG
 	case TCP_MD5SIG:
 	case TCP_MD5SIG_EXT:
-		err = tp->af_specific->md5_parse(sk, optname,
-						 USER_SOCKPTR(optval), optlen);
+		err = tp->af_specific->md5_parse(sk, optname, optval, optlen);
 		break;
 #endif
 	case TCP_USER_TIMEOUT:
@@ -3334,7 +3331,8 @@ int tcp_setsockopt(struct sock *sk, int level, int optname, char __user *optval,
 	if (level != SOL_TCP)
 		return icsk->icsk_af_ops->setsockopt(sk, level, optname,
 						     optval, optlen);
-	return do_tcp_setsockopt(sk, level, optname, optval, optlen);
+	return do_tcp_setsockopt(sk, level, optname, USER_SOCKPTR(optval),
+				 optlen);
 }
 EXPORT_SYMBOL(tcp_setsockopt);
 
-- 
2.27.0

