net: Unbreak compat_sys_{send,recv}msg
I broke them in this commit:
commit 1be374a0518a288147c6a7398792583200a67261
Author: Andy Lutomirski <luto@amacapital.net>
Date: Wed May 22 14:07:44 2013 -0700
net: Block MSG_CMSG_COMPAT in send(m)msg and recv(m)msg
This patch adds __sys_sendmsg and __sys_sendmsg as common helpers that accept
MSG_CMSG_COMPAT and blocks MSG_CMSG_COMPAT at the syscall entrypoints. It
also reverts some unnecessary checks in sys_socketcall.
Apparently I was suffering from underscore blindness the first time around.
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Tested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/socket.c b/net/socket.c
index 9ff6366..4ca1526 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -1956,7 +1956,7 @@
unsigned int name_len;
};
-static int __sys_sendmsg(struct socket *sock, struct msghdr __user *msg,
+static int ___sys_sendmsg(struct socket *sock, struct msghdr __user *msg,
struct msghdr *msg_sys, unsigned int flags,
struct used_address *used_address)
{
@@ -2071,26 +2071,30 @@
* BSD sendmsg interface
*/
-SYSCALL_DEFINE3(sendmsg, int, fd, struct msghdr __user *, msg, unsigned int, flags)
+long __sys_sendmsg(int fd, struct msghdr __user *msg, unsigned flags)
{
int fput_needed, err;
struct msghdr msg_sys;
struct socket *sock;
- if (flags & MSG_CMSG_COMPAT)
- return -EINVAL;
-
sock = sockfd_lookup_light(fd, &err, &fput_needed);
if (!sock)
goto out;
- err = __sys_sendmsg(sock, msg, &msg_sys, flags, NULL);
+ err = ___sys_sendmsg(sock, msg, &msg_sys, flags, NULL);
fput_light(sock->file, fput_needed);
out:
return err;
}
+SYSCALL_DEFINE3(sendmsg, int, fd, struct msghdr __user *, msg, unsigned int, flags)
+{
+ if (flags & MSG_CMSG_COMPAT)
+ return -EINVAL;
+ return __sys_sendmsg(fd, msg, flags);
+}
+
/*
* Linux sendmmsg interface
*/
@@ -2121,15 +2125,16 @@
while (datagrams < vlen) {
if (MSG_CMSG_COMPAT & flags) {
- err = __sys_sendmsg(sock, (struct msghdr __user *)compat_entry,
- &msg_sys, flags, &used_address);
+ err = ___sys_sendmsg(sock, (struct msghdr __user *)compat_entry,
+ &msg_sys, flags, &used_address);
if (err < 0)
break;
err = __put_user(err, &compat_entry->msg_len);
++compat_entry;
} else {
- err = __sys_sendmsg(sock, (struct msghdr __user *)entry,
- &msg_sys, flags, &used_address);
+ err = ___sys_sendmsg(sock,
+ (struct msghdr __user *)entry,
+ &msg_sys, flags, &used_address);
if (err < 0)
break;
err = put_user(err, &entry->msg_len);
@@ -2158,7 +2163,7 @@
return __sys_sendmmsg(fd, mmsg, vlen, flags);
}
-static int __sys_recvmsg(struct socket *sock, struct msghdr __user *msg,
+static int ___sys_recvmsg(struct socket *sock, struct msghdr __user *msg,
struct msghdr *msg_sys, unsigned int flags, int nosec)
{
struct compat_msghdr __user *msg_compat =
@@ -2250,27 +2255,31 @@
* BSD recvmsg interface
*/
-SYSCALL_DEFINE3(recvmsg, int, fd, struct msghdr __user *, msg,
- unsigned int, flags)
+long __sys_recvmsg(int fd, struct msghdr __user *msg, unsigned flags)
{
int fput_needed, err;
struct msghdr msg_sys;
struct socket *sock;
- if (flags & MSG_CMSG_COMPAT)
- return -EINVAL;
-
sock = sockfd_lookup_light(fd, &err, &fput_needed);
if (!sock)
goto out;
- err = __sys_recvmsg(sock, msg, &msg_sys, flags, 0);
+ err = ___sys_recvmsg(sock, msg, &msg_sys, flags, 0);
fput_light(sock->file, fput_needed);
out:
return err;
}
+SYSCALL_DEFINE3(recvmsg, int, fd, struct msghdr __user *, msg,
+ unsigned int, flags)
+{
+ if (flags & MSG_CMSG_COMPAT)
+ return -EINVAL;
+ return __sys_recvmsg(fd, msg, flags);
+}
+
/*
* Linux recvmmsg interface
*/
@@ -2308,17 +2317,18 @@
* No need to ask LSM for more than the first datagram.
*/
if (MSG_CMSG_COMPAT & flags) {
- err = __sys_recvmsg(sock, (struct msghdr __user *)compat_entry,
- &msg_sys, flags & ~MSG_WAITFORONE,
- datagrams);
+ err = ___sys_recvmsg(sock, (struct msghdr __user *)compat_entry,
+ &msg_sys, flags & ~MSG_WAITFORONE,
+ datagrams);
if (err < 0)
break;
err = __put_user(err, &compat_entry->msg_len);
++compat_entry;
} else {
- err = __sys_recvmsg(sock, (struct msghdr __user *)entry,
- &msg_sys, flags & ~MSG_WAITFORONE,
- datagrams);
+ err = ___sys_recvmsg(sock,
+ (struct msghdr __user *)entry,
+ &msg_sys, flags & ~MSG_WAITFORONE,
+ datagrams);
if (err < 0)
break;
err = put_user(err, &entry->msg_len);
@@ -2505,31 +2515,15 @@
(int __user *)a[4]);
break;
case SYS_SENDMSG:
- if (a[2] & MSG_CMSG_COMPAT) {
- err = -EINVAL;
- break;
- }
err = sys_sendmsg(a0, (struct msghdr __user *)a1, a[2]);
break;
case SYS_SENDMMSG:
- if (a[3] & MSG_CMSG_COMPAT) {
- err = -EINVAL;
- break;
- }
err = sys_sendmmsg(a0, (struct mmsghdr __user *)a1, a[2], a[3]);
break;
case SYS_RECVMSG:
- if (a[2] & MSG_CMSG_COMPAT) {
- err = -EINVAL;
- break;
- }
err = sys_recvmsg(a0, (struct msghdr __user *)a1, a[2]);
break;
case SYS_RECVMMSG:
- if (a[3] & MSG_CMSG_COMPAT) {
- err = -EINVAL;
- break;
- }
err = sys_recvmmsg(a0, (struct mmsghdr __user *)a1, a[2], a[3],
(struct timespec __user *)a[4]);
break;