ipc: add shmget syscall wrapper

Provide ksys_shmget() wrapper to avoid in-kernel calls to this syscall.
The ksys_ prefix denotes that this function is meant as a drop-in
replacement for the syscall. In particular, it uses the same calling
convention as sys_shmget().

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: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>

1 files changed, 2 insertions, 2 deletions

diff --git a/ipc/syscall.c b/ipc/syscall.c
index 355c4a644bbf..60bceb19b6f0 100644
--- a/ipc/syscall.c
+++ b/ipc/syscall.c
@@ -92,7 +92,7 @@ SYSCALL_DEFINE6(ipc, unsigned int, call, int, first, unsigned long, second,
         case SHMDT:
                 return sys_shmdt((char __user *)ptr);
         case SHMGET:
-                return sys_shmget(first, second, third);
+                return ksys_shmget(first, second, third);
         case SHMCTL:
                 return sys_shmctl(first, second,
                                    (struct shmid_ds __user *) ptr);
@@ -180,7 +180,7 @@ COMPAT_SYSCALL_DEFINE6(ipc, u32, call, int, first, int, second,
         case SHMDT:
                 return sys_shmdt(compat_ptr(ptr));
         case SHMGET:
-                return sys_shmget(first, (unsigned)second, third);
+                return ksys_shmget(first, (unsigned int)second, third);
         case SHMCTL:
                 return compat_sys_shmctl(first, second, compat_ptr(ptr));
         }