diff options
| author | Dominik Brodowski <linux@dominikbrodowski.net> | 2018-03-13 20:35:57 +0100 |
|---|---|---|
| committer | Dominik Brodowski <linux@dominikbrodowski.net> | 2018-04-02 20:15:15 +0200 |
| commit | e1834a329d6bb5659c14e9e537bd1f750fe3b85e (patch) | |
| tree | d47326548c1db4840cefb1d4e5341df49dabdef6 /net/socket.c | |
| parent | 1255e2690689ba5b72814c8df7bfd9ecf50175aa (diff) | |
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/socket.c')
| -rw-r--r-- | net/socket.c | 38 |
1 files changed, 23 insertions, 15 deletions
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], |