[PATCH 3.11 022/208] net: rework recvmsg handler msg_name and msg_namelen logic
Luis Henriques
luis.henriques at canonical.com
Thu Dec 19 11:52:00 UTC 2013
3.11.10.2 -stable review patch. If anyone has any objections, please let me know.
------------------
From: Hannes Frederic Sowa <hannes at stressinduktion.org>
commit f3d3342602f8bcbf37d7c46641cb9bca7618eb1c upstream.
This patch now always passes msg->msg_namelen as 0. recvmsg handlers must
set msg_namelen to the proper size <= sizeof(struct sockaddr_storage)
to return msg_name to the user.
This prevents numerous uninitialized memory leaks we had in the
recvmsg handlers and makes it harder for new code to accidentally leak
uninitialized memory.
Optimize for the case recvfrom is called with NULL as address. We don't
need to copy the address at all, so set it to NULL before invoking the
recvmsg handler. We can do so, because all the recvmsg handlers must
cope with the case a plain read() is called on them. read() also sets
msg_name to NULL.
Also document these changes in include/linux/net.h as suggested by David
Miller.
Changes since RFC:
Set msg->msg_name = NULL if user specified a NULL in msg_name but had a
non-null msg_namelen in verify_iovec/verify_compat_iovec. This doesn't
affect sendto as it would bail out earlier while trying to copy-in the
address. It also more naturally reflects the logic by the callers of
verify_iovec.
With this change in place I could remove "
if (!uaddr || msg_sys->msg_namelen == 0)
msg->msg_name = NULL
".
This change does not alter the user visible error logic as we ignore
msg_namelen as long as msg_name is NULL.
Also remove two unnecessary curly brackets in ___sys_recvmsg and change
comments to netdev style.
Cc: David Miller <davem at davemloft.net>
Suggested-by: Eric Dumazet <eric.dumazet at gmail.com>
Signed-off-by: Hannes Frederic Sowa <hannes at stressinduktion.org>
Signed-off-by: David S. Miller <davem at davemloft.net>
[ luis: backported to 3.11: adjusted context ]
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
crypto/algif_hash.c | 2 --
crypto/algif_skcipher.c | 1 -
drivers/isdn/mISDN/socket.c | 13 ++++---------
drivers/net/ppp/pppoe.c | 2 --
include/linux/net.h | 8 ++++++++
net/appletalk/ddp.c | 16 +++++++---------
net/atm/common.c | 2 --
net/ax25/af_ax25.c | 4 ++--
net/bluetooth/af_bluetooth.c | 4 ----
net/bluetooth/hci_sock.c | 2 --
net/bluetooth/rfcomm/sock.c | 1 -
net/bluetooth/sco.c | 1 -
net/caif/caif_socket.c | 4 ----
net/compat.c | 3 ++-
net/core/iovec.c | 3 ++-
net/ipx/af_ipx.c | 3 +--
net/irda/af_irda.c | 4 ----
net/iucv/af_iucv.c | 2 --
net/key/af_key.c | 1 -
net/l2tp/l2tp_ppp.c | 2 --
net/llc/af_llc.c | 2 --
net/netlink/af_netlink.c | 2 --
net/netrom/af_netrom.c | 3 +--
net/nfc/llcp_sock.c | 2 --
net/nfc/rawsock.c | 2 --
net/packet/af_packet.c | 32 +++++++++++++++-----------------
net/rds/recv.c | 2 --
net/rose/af_rose.c | 8 +++++---
net/rxrpc/ar-recvmsg.c | 9 ++++++---
net/socket.c | 19 +++++++++++--------
net/tipc/socket.c | 6 ------
net/unix/af_unix.c | 5 -----
net/vmw_vsock/af_vsock.c | 2 --
net/vmw_vsock/vmci_transport.c | 2 --
net/x25/af_x25.c | 3 +--
35 files changed, 65 insertions(+), 112 deletions(-)
diff --git a/crypto/algif_hash.c b/crypto/algif_hash.c
index 0262210..ef5356c 100644
--- a/crypto/algif_hash.c
+++ b/crypto/algif_hash.c
@@ -161,8 +161,6 @@ static int hash_recvmsg(struct kiocb *unused, struct socket *sock,
else if (len < ds)
msg->msg_flags |= MSG_TRUNC;
- msg->msg_namelen = 0;
-
lock_sock(sk);
if (ctx->more) {
ctx->more = 0;
diff --git a/crypto/algif_skcipher.c b/crypto/algif_skcipher.c
index a1c4f0a..6a6dfc0 100644
--- a/crypto/algif_skcipher.c
+++ b/crypto/algif_skcipher.c
@@ -432,7 +432,6 @@ static int skcipher_recvmsg(struct kiocb *unused, struct socket *sock,
long copied = 0;
lock_sock(sk);
- msg->msg_namelen = 0;
for (iov = msg->msg_iov, iovlen = msg->msg_iovlen; iovlen > 0;
iovlen--, iov++) {
unsigned long seglen = iov->iov_len;
diff --git a/drivers/isdn/mISDN/socket.c b/drivers/isdn/mISDN/socket.c
index e47dcb9..5cefb47 100644
--- a/drivers/isdn/mISDN/socket.c
+++ b/drivers/isdn/mISDN/socket.c
@@ -117,7 +117,6 @@ mISDN_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
{
struct sk_buff *skb;
struct sock *sk = sock->sk;
- struct sockaddr_mISDN *maddr;
int copied, err;
@@ -135,9 +134,9 @@ mISDN_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
if (!skb)
return err;
- if (msg->msg_namelen >= sizeof(struct sockaddr_mISDN)) {
- msg->msg_namelen = sizeof(struct sockaddr_mISDN);
- maddr = (struct sockaddr_mISDN *)msg->msg_name;
+ if (msg->msg_name) {
+ struct sockaddr_mISDN *maddr = msg->msg_name;
+
maddr->family = AF_ISDN;
maddr->dev = _pms(sk)->dev->id;
if ((sk->sk_protocol == ISDN_P_LAPD_TE) ||
@@ -150,11 +149,7 @@ mISDN_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
maddr->sapi = _pms(sk)->ch.addr & 0xFF;
maddr->tei = (_pms(sk)->ch.addr >> 8) & 0xFF;
}
- } else {
- if (msg->msg_namelen)
- printk(KERN_WARNING "%s: too small namelen %d\n",
- __func__, msg->msg_namelen);
- msg->msg_namelen = 0;
+ msg->msg_namelen = sizeof(*maddr);
}
copied = skb->len + MISDN_HEADER_LEN;
diff --git a/drivers/net/ppp/pppoe.c b/drivers/net/ppp/pppoe.c
index 5f66e30..82ee6ed 100644
--- a/drivers/net/ppp/pppoe.c
+++ b/drivers/net/ppp/pppoe.c
@@ -979,8 +979,6 @@ static int pppoe_recvmsg(struct kiocb *iocb, struct socket *sock,
if (error < 0)
goto end;
- m->msg_namelen = 0;
-
if (skb) {
total_len = min_t(size_t, total_len, skb->len);
error = skb_copy_datagram_iovec(skb, 0, m->msg_iov, total_len);
diff --git a/include/linux/net.h b/include/linux/net.h
index 4f27575..8bd9d92 100644
--- a/include/linux/net.h
+++ b/include/linux/net.h
@@ -163,6 +163,14 @@ struct proto_ops {
#endif
int (*sendmsg) (struct kiocb *iocb, struct socket *sock,
struct msghdr *m, size_t total_len);
+ /* Notes for implementing recvmsg:
+ * ===============================
+ * msg->msg_namelen should get updated by the recvmsg handlers
+ * iff msg_name != NULL. It is by default 0 to prevent
+ * returning uninitialized memory to user space. The recvfrom
+ * handlers can assume that msg.msg_name is either NULL or has
+ * a minimum size of sizeof(struct sockaddr_storage).
+ */
int (*recvmsg) (struct kiocb *iocb, struct socket *sock,
struct msghdr *m, size_t total_len,
int flags);
diff --git a/net/appletalk/ddp.c b/net/appletalk/ddp.c
index 7fee50d..7d424ac 100644
--- a/net/appletalk/ddp.c
+++ b/net/appletalk/ddp.c
@@ -1735,7 +1735,6 @@ static int atalk_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr
size_t size, int flags)
{
struct sock *sk = sock->sk;
- struct sockaddr_at *sat = (struct sockaddr_at *)msg->msg_name;
struct ddpehdr *ddp;
int copied = 0;
int offset = 0;
@@ -1764,14 +1763,13 @@ static int atalk_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr
}
err = skb_copy_datagram_iovec(skb, offset, msg->msg_iov, copied);
- if (!err) {
- if (sat) {
- sat->sat_family = AF_APPLETALK;
- sat->sat_port = ddp->deh_sport;
- sat->sat_addr.s_node = ddp->deh_snode;
- sat->sat_addr.s_net = ddp->deh_snet;
- }
- msg->msg_namelen = sizeof(*sat);
+ if (!err && msg->msg_name) {
+ struct sockaddr_at *sat = msg->msg_name;
+ sat->sat_family = AF_APPLETALK;
+ sat->sat_port = ddp->deh_sport;
+ sat->sat_addr.s_node = ddp->deh_snode;
+ sat->sat_addr.s_net = ddp->deh_snet;
+ msg->msg_namelen = sizeof(*sat);
}
skb_free_datagram(sk, skb); /* Free the datagram. */
diff --git a/net/atm/common.c b/net/atm/common.c
index 737bef5..7b49100 100644
--- a/net/atm/common.c
+++ b/net/atm/common.c
@@ -531,8 +531,6 @@ int vcc_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg,
struct sk_buff *skb;
int copied, error = -EINVAL;
- msg->msg_namelen = 0;
-
if (sock->state != SS_CONNECTED)
return -ENOTCONN;
diff --git a/net/ax25/af_ax25.c b/net/ax25/af_ax25.c
index 4b4d2b7..78c474f 100644
--- a/net/ax25/af_ax25.c
+++ b/net/ax25/af_ax25.c
@@ -1636,11 +1636,11 @@ static int ax25_recvmsg(struct kiocb *iocb, struct socket *sock,
skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
- if (msg->msg_namelen != 0) {
- struct sockaddr_ax25 *sax = (struct sockaddr_ax25 *)msg->msg_name;
+ if (msg->msg_name) {
ax25_digi digi;
ax25_address src;
const unsigned char *mac = skb_mac_header(skb);
+ struct sockaddr_ax25 *sax = msg->msg_name;
memset(sax, 0, sizeof(struct full_sockaddr_ax25));
ax25_addr_parse(mac + 1, skb->data - mac - 1, &src, NULL,
diff --git a/net/bluetooth/af_bluetooth.c b/net/bluetooth/af_bluetooth.c
index 9096137..6629cdc 100644
--- a/net/bluetooth/af_bluetooth.c
+++ b/net/bluetooth/af_bluetooth.c
@@ -221,8 +221,6 @@ int bt_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
if (flags & (MSG_OOB))
return -EOPNOTSUPP;
- msg->msg_namelen = 0;
-
skb = skb_recv_datagram(sk, flags, noblock, &err);
if (!skb) {
if (sk->sk_shutdown & RCV_SHUTDOWN)
@@ -287,8 +285,6 @@ int bt_sock_stream_recvmsg(struct kiocb *iocb, struct socket *sock,
if (flags & MSG_OOB)
return -EOPNOTSUPP;
- msg->msg_namelen = 0;
-
BT_DBG("sk %p size %zu", sk, size);
lock_sock(sk);
diff --git a/net/bluetooth/hci_sock.c b/net/bluetooth/hci_sock.c
index 9bd7d95..fa4bf66 100644
--- a/net/bluetooth/hci_sock.c
+++ b/net/bluetooth/hci_sock.c
@@ -752,8 +752,6 @@ static int hci_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
if (!skb)
return err;
- msg->msg_namelen = 0;
-
copied = skb->len;
if (len < copied) {
msg->msg_flags |= MSG_TRUNC;
diff --git a/net/bluetooth/rfcomm/sock.c b/net/bluetooth/rfcomm/sock.c
index 30b3721..c1c6028 100644
--- a/net/bluetooth/rfcomm/sock.c
+++ b/net/bluetooth/rfcomm/sock.c
@@ -608,7 +608,6 @@ static int rfcomm_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
if (test_and_clear_bit(RFCOMM_DEFER_SETUP, &d->flags)) {
rfcomm_dlc_accept(d);
- msg->msg_namelen = 0;
return 0;
}
diff --git a/net/bluetooth/sco.c b/net/bluetooth/sco.c
index e7bd4ee..2bb1d3a 100644
--- a/net/bluetooth/sco.c
+++ b/net/bluetooth/sco.c
@@ -700,7 +700,6 @@ static int sco_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
test_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags)) {
sco_conn_defer_accept(pi->conn->hcon, 0);
sk->sk_state = BT_CONFIG;
- msg->msg_namelen = 0;
release_sock(sk);
return 0;
diff --git a/net/caif/caif_socket.c b/net/caif/caif_socket.c
index 05a41c7..d6be3ed 100644
--- a/net/caif/caif_socket.c
+++ b/net/caif/caif_socket.c
@@ -286,8 +286,6 @@ static int caif_seqpkt_recvmsg(struct kiocb *iocb, struct socket *sock,
if (m->msg_flags&MSG_OOB)
goto read_error;
- m->msg_namelen = 0;
-
skb = skb_recv_datagram(sk, flags, 0 , &ret);
if (!skb)
goto read_error;
@@ -361,8 +359,6 @@ static int caif_stream_recvmsg(struct kiocb *iocb, struct socket *sock,
if (flags&MSG_OOB)
goto out;
- msg->msg_namelen = 0;
-
/*
* Lock the socket to prevent queue disordering
* while sleeps in memcpy_tomsg
diff --git a/net/compat.c b/net/compat.c
index 8903258..618c6a8 100644
--- a/net/compat.c
+++ b/net/compat.c
@@ -93,7 +93,8 @@ int verify_compat_iovec(struct msghdr *kern_msg, struct iovec *kern_iov,
if (err < 0)
return err;
}
- kern_msg->msg_name = kern_address;
+ if (kern_msg->msg_name)
+ kern_msg->msg_name = kern_address;
} else
kern_msg->msg_name = NULL;
diff --git a/net/core/iovec.c b/net/core/iovec.c
index de178e4..9a31515 100644
--- a/net/core/iovec.c
+++ b/net/core/iovec.c
@@ -48,7 +48,8 @@ int verify_iovec(struct msghdr *m, struct iovec *iov, struct sockaddr_storage *a
if (err < 0)
return err;
}
- m->msg_name = address;
+ if (m->msg_name)
+ m->msg_name = address;
} else {
m->msg_name = NULL;
}
diff --git a/net/ipx/af_ipx.c b/net/ipx/af_ipx.c
index 7a1e0fc..e096025 100644
--- a/net/ipx/af_ipx.c
+++ b/net/ipx/af_ipx.c
@@ -1823,8 +1823,6 @@ static int ipx_recvmsg(struct kiocb *iocb, struct socket *sock,
if (skb->tstamp.tv64)
sk->sk_stamp = skb->tstamp;
- msg->msg_namelen = sizeof(*sipx);
-
if (sipx) {
sipx->sipx_family = AF_IPX;
sipx->sipx_port = ipx->ipx_source.sock;
@@ -1832,6 +1830,7 @@ static int ipx_recvmsg(struct kiocb *iocb, struct socket *sock,
sipx->sipx_network = IPX_SKB_CB(skb)->ipx_source_net;
sipx->sipx_type = ipx->ipx_type;
sipx->sipx_zero = 0;
+ msg->msg_namelen = sizeof(*sipx);
}
rc = copied;
diff --git a/net/irda/af_irda.c b/net/irda/af_irda.c
index 0578d4f..a5e62ef5 100644
--- a/net/irda/af_irda.c
+++ b/net/irda/af_irda.c
@@ -1385,8 +1385,6 @@ static int irda_recvmsg_dgram(struct kiocb *iocb, struct socket *sock,
IRDA_DEBUG(4, "%s()\n", __func__);
- msg->msg_namelen = 0;
-
skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT,
flags & MSG_DONTWAIT, &err);
if (!skb)
@@ -1451,8 +1449,6 @@ static int irda_recvmsg_stream(struct kiocb *iocb, struct socket *sock,
target = sock_rcvlowat(sk, flags & MSG_WAITALL, size);
timeo = sock_rcvtimeo(sk, noblock);
- msg->msg_namelen = 0;
-
do {
int chunk;
struct sk_buff *skb = skb_dequeue(&sk->sk_receive_queue);
diff --git a/net/iucv/af_iucv.c b/net/iucv/af_iucv.c
index 168aff5..c4b7218 100644
--- a/net/iucv/af_iucv.c
+++ b/net/iucv/af_iucv.c
@@ -1324,8 +1324,6 @@ static int iucv_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
int err = 0;
u32 offset;
- msg->msg_namelen = 0;
-
if ((sk->sk_state == IUCV_DISCONN) &&
skb_queue_empty(&iucv->backlog_skb_q) &&
skb_queue_empty(&sk->sk_receive_queue) &&
diff --git a/net/key/af_key.c b/net/key/af_key.c
index ab8bd2c..66f51c5 100644
--- a/net/key/af_key.c
+++ b/net/key/af_key.c
@@ -3623,7 +3623,6 @@ static int pfkey_recvmsg(struct kiocb *kiocb,
if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT))
goto out;
- msg->msg_namelen = 0;
skb = skb_recv_datagram(sk, flags, flags & MSG_DONTWAIT, &err);
if (skb == NULL)
goto out;
diff --git a/net/l2tp/l2tp_ppp.c b/net/l2tp/l2tp_ppp.c
index 8c46b27..44441c0 100644
--- a/net/l2tp/l2tp_ppp.c
+++ b/net/l2tp/l2tp_ppp.c
@@ -197,8 +197,6 @@ static int pppol2tp_recvmsg(struct kiocb *iocb, struct socket *sock,
if (sk->sk_state & PPPOX_BOUND)
goto end;
- msg->msg_namelen = 0;
-
err = 0;
skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT,
flags & MSG_DONTWAIT, &err);
diff --git a/net/llc/af_llc.c b/net/llc/af_llc.c
index 48aaa89..8870988 100644
--- a/net/llc/af_llc.c
+++ b/net/llc/af_llc.c
@@ -720,8 +720,6 @@ static int llc_ui_recvmsg(struct kiocb *iocb, struct socket *sock,
int target; /* Read at least this many bytes */
long timeo;
- msg->msg_namelen = 0;
-
lock_sock(sk);
copied = -ENOTCONN;
if (unlikely(sk->sk_type == SOCK_STREAM && sk->sk_state == TCP_LISTEN))
diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c
index 0c61b59..90b654b 100644
--- a/net/netlink/af_netlink.c
+++ b/net/netlink/af_netlink.c
@@ -2317,8 +2317,6 @@ static int netlink_recvmsg(struct kiocb *kiocb, struct socket *sock,
}
#endif
- msg->msg_namelen = 0;
-
copied = data_skb->len;
if (len < copied) {
msg->msg_flags |= MSG_TRUNC;
diff --git a/net/netrom/af_netrom.c b/net/netrom/af_netrom.c
index 698814b..53c19a3 100644
--- a/net/netrom/af_netrom.c
+++ b/net/netrom/af_netrom.c
@@ -1179,10 +1179,9 @@ static int nr_recvmsg(struct kiocb *iocb, struct socket *sock,
sax->sax25_family = AF_NETROM;
skb_copy_from_linear_data_offset(skb, 7, sax->sax25_call.ax25_call,
AX25_ADDR_LEN);
+ msg->msg_namelen = sizeof(*sax);
}
- msg->msg_namelen = sizeof(*sax);
-
skb_free_datagram(sk, skb);
release_sock(sk);
diff --git a/net/nfc/llcp_sock.c b/net/nfc/llcp_sock.c
index d308402..824c605 100644
--- a/net/nfc/llcp_sock.c
+++ b/net/nfc/llcp_sock.c
@@ -807,8 +807,6 @@ static int llcp_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
pr_debug("%p %zu\n", sk, len);
- msg->msg_namelen = 0;
-
lock_sock(sk);
if (sk->sk_state == LLCP_CLOSED &&
diff --git a/net/nfc/rawsock.c b/net/nfc/rawsock.c
index 313bf1b..5d11f4a 100644
--- a/net/nfc/rawsock.c
+++ b/net/nfc/rawsock.c
@@ -241,8 +241,6 @@ static int rawsock_recvmsg(struct kiocb *iocb, struct socket *sock,
if (!skb)
return rc;
- msg->msg_namelen = 0;
-
copied = skb->len;
if (len < copied) {
msg->msg_flags |= MSG_TRUNC;
diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
index 75c8bbf..739c50d 100644
--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -2694,7 +2694,6 @@ static int packet_recvmsg(struct kiocb *iocb, struct socket *sock,
struct sock *sk = sock->sk;
struct sk_buff *skb;
int copied, err;
- struct sockaddr_ll *sll;
int vnet_hdr_len = 0;
err = -EINVAL;
@@ -2777,22 +2776,10 @@ static int packet_recvmsg(struct kiocb *iocb, struct socket *sock,
goto out_free;
}
- /*
- * If the address length field is there to be filled in, we fill
- * it in now.
- */
-
- sll = &PACKET_SKB_CB(skb)->sa.ll;
- if (sock->type == SOCK_PACKET)
- msg->msg_namelen = sizeof(struct sockaddr_pkt);
- else
- msg->msg_namelen = sll->sll_halen + offsetof(struct sockaddr_ll, sll_addr);
-
- /*
- * You lose any data beyond the buffer you gave. If it worries a
- * user program they can ask the device for its MTU anyway.
+ /* You lose any data beyond the buffer you gave. If it worries
+ * a user program they can ask the device for its MTU
+ * anyway.
*/
-
copied = skb->len;
if (copied > len) {
copied = len;
@@ -2805,9 +2792,20 @@ static int packet_recvmsg(struct kiocb *iocb, struct socket *sock,
sock_recv_ts_and_drops(msg, sk, skb);
- if (msg->msg_name)
+ if (msg->msg_name) {
+ /* If the address length field is there to be filled
+ * in, we fill it in now.
+ */
+ if (sock->type == SOCK_PACKET) {
+ msg->msg_namelen = sizeof(struct sockaddr_pkt);
+ } else {
+ struct sockaddr_ll *sll = &PACKET_SKB_CB(skb)->sa.ll;
+ msg->msg_namelen = sll->sll_halen +
+ offsetof(struct sockaddr_ll, sll_addr);
+ }
memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa,
msg->msg_namelen);
+ }
if (pkt_sk(sk)->auxdata) {
struct tpacket_auxdata aux;
diff --git a/net/rds/recv.c b/net/rds/recv.c
index 9f0f17c..de339b2 100644
--- a/net/rds/recv.c
+++ b/net/rds/recv.c
@@ -410,8 +410,6 @@ int rds_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg,
rdsdebug("size %zu flags 0x%x timeo %ld\n", size, msg_flags, timeo);
- msg->msg_namelen = 0;
-
if (msg_flags & MSG_OOB)
goto out;
diff --git a/net/rose/af_rose.c b/net/rose/af_rose.c
index e98fcfb..33af772 100644
--- a/net/rose/af_rose.c
+++ b/net/rose/af_rose.c
@@ -1216,7 +1216,6 @@ static int rose_recvmsg(struct kiocb *iocb, struct socket *sock,
{
struct sock *sk = sock->sk;
struct rose_sock *rose = rose_sk(sk);
- struct sockaddr_rose *srose = (struct sockaddr_rose *)msg->msg_name;
size_t copied;
unsigned char *asmptr;
struct sk_buff *skb;
@@ -1252,8 +1251,11 @@ static int rose_recvmsg(struct kiocb *iocb, struct socket *sock,
skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
- if (srose != NULL) {
- memset(srose, 0, msg->msg_namelen);
+ if (msg->msg_name) {
+ struct sockaddr_rose *srose;
+
+ memset(msg->msg_name, 0, sizeof(struct full_sockaddr_rose));
+ srose = msg->msg_name;
srose->srose_family = AF_ROSE;
srose->srose_addr = rose->dest_addr;
srose->srose_call = rose->dest_call;
diff --git a/net/rxrpc/ar-recvmsg.c b/net/rxrpc/ar-recvmsg.c
index 4b48687..898492a 100644
--- a/net/rxrpc/ar-recvmsg.c
+++ b/net/rxrpc/ar-recvmsg.c
@@ -143,10 +143,13 @@ int rxrpc_recvmsg(struct kiocb *iocb, struct socket *sock,
/* copy the peer address and timestamp */
if (!continue_call) {
- if (msg->msg_name && msg->msg_namelen > 0)
+ if (msg->msg_name) {
+ size_t len =
+ sizeof(call->conn->trans->peer->srx);
memcpy(msg->msg_name,
- &call->conn->trans->peer->srx,
- sizeof(call->conn->trans->peer->srx));
+ &call->conn->trans->peer->srx, len);
+ msg->msg_namelen = len;
+ }
sock_recv_ts_and_drops(msg, &rx->sk, skb);
}
diff --git a/net/socket.c b/net/socket.c
index 4b94643..5158ff7 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -1849,8 +1849,10 @@ SYSCALL_DEFINE6(recvfrom, int, fd, void __user *, ubuf, size_t, size,
msg.msg_iov = &iov;
iov.iov_len = size;
iov.iov_base = ubuf;
- msg.msg_name = (struct sockaddr *)&address;
- msg.msg_namelen = sizeof(address);
+ /* Save some cycles and don't copy the address if not needed */
+ msg.msg_name = addr ? (struct sockaddr *)&address : NULL;
+ /* We assume all kernel code knows the size of sockaddr_storage */
+ msg.msg_namelen = 0;
if (sock->file->f_flags & O_NONBLOCK)
flags |= MSG_DONTWAIT;
err = sock_recvmsg(sock, &msg, size, flags);
@@ -2230,16 +2232,14 @@ static int ___sys_recvmsg(struct socket *sock, struct msghdr __user *msg,
goto out;
}
- /*
- * Save the user-mode address (verify_iovec will change the
- * kernel msghdr to use the kernel address space)
+ /* Save the user-mode address (verify_iovec will change the
+ * kernel msghdr to use the kernel address space)
*/
-
uaddr = (__force void __user *)msg_sys->msg_name;
uaddr_len = COMPAT_NAMELEN(msg);
- if (MSG_CMSG_COMPAT & flags) {
+ if (MSG_CMSG_COMPAT & flags)
err = verify_compat_iovec(msg_sys, iov, &addr, VERIFY_WRITE);
- } else
+ else
err = verify_iovec(msg_sys, iov, &addr, VERIFY_WRITE);
if (err < 0)
goto out_freeiov;
@@ -2248,6 +2248,9 @@ static int ___sys_recvmsg(struct socket *sock, struct msghdr __user *msg,
cmsg_ptr = (unsigned long)msg_sys->msg_control;
msg_sys->msg_flags = flags & (MSG_CMSG_CLOEXEC|MSG_CMSG_COMPAT);
+ /* We assume all kernel code knows the size of sockaddr_storage */
+ msg_sys->msg_namelen = 0;
+
if (sock->file->f_flags & O_NONBLOCK)
flags |= MSG_DONTWAIT;
err = (nosec ? sock_recvmsg_nosec : sock_recvmsg)(sock, msg_sys,
diff --git a/net/tipc/socket.c b/net/tipc/socket.c
index 6cc7ddd..dffdbea 100644
--- a/net/tipc/socket.c
+++ b/net/tipc/socket.c
@@ -984,9 +984,6 @@ static int recv_msg(struct kiocb *iocb, struct socket *sock,
goto exit;
}
- /* will be updated in set_orig_addr() if needed */
- m->msg_namelen = 0;
-
timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
restart:
@@ -1095,9 +1092,6 @@ static int recv_stream(struct kiocb *iocb, struct socket *sock,
goto exit;
}
- /* will be updated in set_orig_addr() if needed */
- m->msg_namelen = 0;
-
target = sock_rcvlowat(sk, flags & MSG_WAITALL, buf_len);
timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index e64bbcf..6c66e8d 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -1762,7 +1762,6 @@ static void unix_copy_addr(struct msghdr *msg, struct sock *sk)
{
struct unix_sock *u = unix_sk(sk);
- msg->msg_namelen = 0;
if (u->addr) {
msg->msg_namelen = u->addr->len;
memcpy(msg->msg_name, u->addr->name, u->addr->len);
@@ -1786,8 +1785,6 @@ static int unix_dgram_recvmsg(struct kiocb *iocb, struct socket *sock,
if (flags&MSG_OOB)
goto out;
- msg->msg_namelen = 0;
-
err = mutex_lock_interruptible(&u->readlock);
if (err) {
err = sock_intr_errno(sock_rcvtimeo(sk, noblock));
@@ -1927,8 +1924,6 @@ static int unix_stream_recvmsg(struct kiocb *iocb, struct socket *sock,
target = sock_rcvlowat(sk, flags&MSG_WAITALL, size);
timeo = sock_rcvtimeo(sk, flags&MSG_DONTWAIT);
- msg->msg_namelen = 0;
-
/* Lock the socket to prevent queue disordering
* while sleeps in memcpy_tomsg
*/
diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
index 4d93346..16f721c 100644
--- a/net/vmw_vsock/af_vsock.c
+++ b/net/vmw_vsock/af_vsock.c
@@ -1663,8 +1663,6 @@ vsock_stream_recvmsg(struct kiocb *kiocb,
vsk = vsock_sk(sk);
err = 0;
- msg->msg_namelen = 0;
-
lock_sock(sk);
if (sk->sk_state != SS_CONNECTED) {
diff --git a/net/vmw_vsock/vmci_transport.c b/net/vmw_vsock/vmci_transport.c
index ffc11df..73ca104 100644
--- a/net/vmw_vsock/vmci_transport.c
+++ b/net/vmw_vsock/vmci_transport.c
@@ -1746,8 +1746,6 @@ static int vmci_transport_dgram_dequeue(struct kiocb *kiocb,
if (flags & MSG_OOB || flags & MSG_ERRQUEUE)
return -EOPNOTSUPP;
- msg->msg_namelen = 0;
-
/* Retrieve the head sk_buff from the socket's receive queue. */
err = 0;
skb = skb_recv_datagram(&vsk->sk, flags, noblock, &err);
diff --git a/net/x25/af_x25.c b/net/x25/af_x25.c
index 45a3ab5..7622789 100644
--- a/net/x25/af_x25.c
+++ b/net/x25/af_x25.c
@@ -1340,10 +1340,9 @@ static int x25_recvmsg(struct kiocb *iocb, struct socket *sock,
if (sx25) {
sx25->sx25_family = AF_X25;
sx25->sx25_addr = x25->dest_addr;
+ msg->msg_namelen = sizeof(*sx25);
}
- msg->msg_namelen = sizeof(struct sockaddr_x25);
-
x25_check_rbuf(sk);
rc = copied;
out_free_dgram:
--
1.8.3.2
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