From 157b334aa84dc5a4edcbf056b7254263e4112ba8 Mon Sep 17 00:00:00 2001 From: Dominik Brodowski Date: Fri, 16 Mar 2018 17:10:50 +0100 Subject: [PATCH] net: socket: add __compat_sys_recvmmsg() helper; remove in-kernel call to compat syscall Using the net-internal helper __compat_sys_recvmmsg() allows us to avoid the internal calls to the compat_sys_recvmmsg() syscall. 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 Cc: netdev@vger.kernel.org Signed-off-by: Dominik Brodowski --- net/compat.c | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-) diff --git a/net/compat.c b/net/compat.c index cdf5b0c1b962..7b2ae42a1598 100644 --- a/net/compat.c +++ b/net/compat.c @@ -787,9 +787,9 @@ COMPAT_SYSCALL_DEFINE6(recvfrom, int, fd, void __user *, buf, compat_size_t, len return __compat_sys_recvfrom(fd, buf, len, flags, addr, addrlen); } -COMPAT_SYSCALL_DEFINE5(recvmmsg, int, fd, struct compat_mmsghdr __user *, mmsg, - unsigned int, vlen, unsigned int, flags, - struct compat_timespec __user *, timeout) +static int __compat_sys_recvmmsg(int fd, struct compat_mmsghdr __user *mmsg, + unsigned int vlen, unsigned int flags, + struct compat_timespec __user *timeout) { int datagrams; struct timespec ktspec; @@ -809,6 +809,13 @@ COMPAT_SYSCALL_DEFINE5(recvmmsg, int, fd, struct compat_mmsghdr __user *, mmsg, return datagrams; } +COMPAT_SYSCALL_DEFINE5(recvmmsg, int, fd, struct compat_mmsghdr __user *, mmsg, + unsigned int, vlen, unsigned int, flags, + struct compat_timespec __user *, timeout) +{ + return __compat_sys_recvmmsg(fd, mmsg, vlen, flags, timeout); +} + COMPAT_SYSCALL_DEFINE2(socketcall, int, call, u32 __user *, args) { u32 a[AUDITSC_ARGS]; @@ -895,8 +902,8 @@ COMPAT_SYSCALL_DEFINE2(socketcall, int, call, u32 __user *, args) ret = compat_sys_recvmsg(a0, compat_ptr(a1), a[2]); break; case SYS_RECVMMSG: - ret = compat_sys_recvmmsg(a0, compat_ptr(a1), a[2], a[3], - compat_ptr(a[4])); + ret = __compat_sys_recvmmsg(a0, compat_ptr(a1), a[2], a[3], + compat_ptr(a[4])); break; case SYS_ACCEPT4: ret = __sys_accept4(a0, compat_ptr(a1), compat_ptr(a[2]), a[3]); -- GitLab