aboutsummaryrefslogtreecommitdiff
path: root/net
diff options
context:
space:
mode:
authorDominik Brodowski <linux@dominikbrodowski.net>2018-03-13 20:35:57 +0100
committerDominik Brodowski <linux@dominikbrodowski.net>2018-04-02 20:15:15 +0200
commite1834a329d6bb5659c14e9e537bd1f750fe3b85e (patch)
treed47326548c1db4840cefb1d4e5341df49dabdef6 /net
parent1255e2690689ba5b72814c8df7bfd9ecf50175aa (diff)
downloadlinux-stericsson-e1834a329d6bb5659c14e9e537bd1f750fe3b85e.tar.gz
net: socket: move check for forbid_cmsg_compat to __sys_...msg()
The non-compat codepaths for sys_...msg() verify that MSG_CMSG_COMPAT is not set. By moving this check to the __sys_...msg() functions (and making it dependent on a static flag passed to this function), we can call the __sys...msg() functions instead of the syscall functions in all cases. __sys_recvmmsg() does not need this trickery, as the check is handled within the do_sys_recvmmsg() function internal to net/socket.c. This patch is part of a series which removes in-kernel calls to syscalls. On this basis, the syscall entry path can be streamlined. For details, see http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net Cc: David S. Miller <davem@davemloft.net> Cc: netdev@vger.kernel.org Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Diffstat (limited to 'net')
-rw-r--r--net/compat.c8
-rw-r--r--net/socket.c38
2 files changed, 28 insertions, 18 deletions
diff --git a/net/compat.c b/net/compat.c
index f1ec23e9dfce..5caa48987bb2 100644
--- a/net/compat.c
+++ b/net/compat.c
@@ -736,19 +736,21 @@ static unsigned char nas[21] = {
COMPAT_SYSCALL_DEFINE3(sendmsg, int, fd, struct compat_msghdr __user *, msg, unsigned int, flags)
{
- return __sys_sendmsg(fd, (struct user_msghdr __user *)msg, flags | MSG_CMSG_COMPAT);
+ return __sys_sendmsg(fd, (struct user_msghdr __user *)msg,
+ flags | MSG_CMSG_COMPAT, false);
}
COMPAT_SYSCALL_DEFINE4(sendmmsg, int, fd, struct compat_mmsghdr __user *, mmsg,
unsigned int, vlen, unsigned int, flags)
{
return __sys_sendmmsg(fd, (struct mmsghdr __user *)mmsg, vlen,
- flags | MSG_CMSG_COMPAT);
+ flags | MSG_CMSG_COMPAT, false);
}
COMPAT_SYSCALL_DEFINE3(recvmsg, int, fd, struct compat_msghdr __user *, msg, unsigned int, flags)
{
- return __sys_recvmsg(fd, (struct user_msghdr __user *)msg, flags | MSG_CMSG_COMPAT);
+ return __sys_recvmsg(fd, (struct user_msghdr __user *)msg,
+ flags | MSG_CMSG_COMPAT, false);
}
COMPAT_SYSCALL_DEFINE4(recv, int, fd, void __user *, buf, compat_size_t, len, unsigned int, flags)
diff --git a/net/socket.c b/net/socket.c
index 54d19b0edab1..a70793a7ce78 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -2137,12 +2137,16 @@ out_freeiov:
* BSD sendmsg interface
*/
-long __sys_sendmsg(int fd, struct user_msghdr __user *msg, unsigned flags)
+long __sys_sendmsg(int fd, struct user_msghdr __user *msg, unsigned int flags,
+ bool forbid_cmsg_compat)
{
int fput_needed, err;
struct msghdr msg_sys;
struct socket *sock;
+ if (forbid_cmsg_compat && (flags & MSG_CMSG_COMPAT))
+ return -EINVAL;
+
sock = sockfd_lookup_light(fd, &err, &fput_needed);
if (!sock)
goto out;
@@ -2156,9 +2160,7 @@ out:
SYSCALL_DEFINE3(sendmsg, int, fd, struct user_msghdr __user *, msg, unsigned int, flags)
{
- if (flags & MSG_CMSG_COMPAT)
- return -EINVAL;
- return __sys_sendmsg(fd, msg, flags);
+ return __sys_sendmsg(fd, msg, flags, true);
}
/*
@@ -2166,7 +2168,7 @@ SYSCALL_DEFINE3(sendmsg, int, fd, struct user_msghdr __user *, msg, unsigned int
*/
int __sys_sendmmsg(int fd, struct mmsghdr __user *mmsg, unsigned int vlen,
- unsigned int flags)
+ unsigned int flags, bool forbid_cmsg_compat)
{
int fput_needed, err, datagrams;
struct socket *sock;
@@ -2176,6 +2178,9 @@ int __sys_sendmmsg(int fd, struct mmsghdr __user *mmsg, unsigned int vlen,
struct used_address used_address;
unsigned int oflags = flags;
+ if (forbid_cmsg_compat && (flags & MSG_CMSG_COMPAT))
+ return -EINVAL;
+
if (vlen > UIO_MAXIOV)
vlen = UIO_MAXIOV;
@@ -2232,9 +2237,7 @@ int __sys_sendmmsg(int fd, struct mmsghdr __user *mmsg, unsigned int vlen,
SYSCALL_DEFINE4(sendmmsg, int, fd, struct mmsghdr __user *, mmsg,
unsigned int, vlen, unsigned int, flags)
{
- if (flags & MSG_CMSG_COMPAT)
- return -EINVAL;
- return __sys_sendmmsg(fd, mmsg, vlen, flags);
+ return __sys_sendmmsg(fd, mmsg, vlen, flags, true);
}
static int ___sys_recvmsg(struct socket *sock, struct user_msghdr __user *msg,
@@ -2307,12 +2310,16 @@ out_freeiov:
* BSD recvmsg interface
*/
-long __sys_recvmsg(int fd, struct user_msghdr __user *msg, unsigned flags)
+long __sys_recvmsg(int fd, struct user_msghdr __user *msg, unsigned int flags,
+ bool forbid_cmsg_compat)
{
int fput_needed, err;
struct msghdr msg_sys;
struct socket *sock;
+ if (forbid_cmsg_compat && (flags & MSG_CMSG_COMPAT))
+ return -EINVAL;
+
sock = sockfd_lookup_light(fd, &err, &fput_needed);
if (!sock)
goto out;
@@ -2327,9 +2334,7 @@ out:
SYSCALL_DEFINE3(recvmsg, int, fd, struct user_msghdr __user *, msg,
unsigned int, flags)
{
- if (flags & MSG_CMSG_COMPAT)
- return -EINVAL;
- return __sys_recvmsg(fd, msg, flags);
+ return __sys_recvmsg(fd, msg, flags, true);
}
/*
@@ -2580,13 +2585,16 @@ SYSCALL_DEFINE2(socketcall, int, call, unsigned long __user *, args)
(int __user *)a[4]);
break;
case SYS_SENDMSG:
- err = sys_sendmsg(a0, (struct user_msghdr __user *)a1, a[2]);
+ err = __sys_sendmsg(a0, (struct user_msghdr __user *)a1,
+ a[2], true);
break;
case SYS_SENDMMSG:
- err = sys_sendmmsg(a0, (struct mmsghdr __user *)a1, a[2], a[3]);
+ err = __sys_sendmmsg(a0, (struct mmsghdr __user *)a1, a[2],
+ a[3], true);
break;
case SYS_RECVMSG:
- err = sys_recvmsg(a0, (struct user_msghdr __user *)a1, a[2]);
+ err = __sys_recvmsg(a0, (struct user_msghdr __user *)a1,
+ a[2], true);
break;
case SYS_RECVMMSG:
err = do_sys_recvmmsg(a0, (struct mmsghdr __user *)a1, a[2],