kernel: add ksys_setsid() helper; remove in-kernel call to sys_setsid()
Using this helper allows us to avoid the in-kernel call to the
sys_setsid() 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_setsid().
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>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
diff --git a/kernel/sys.c b/kernel/sys.c
index 550f477..ad69218 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -1150,7 +1150,7 @@
change_pid(curr, PIDTYPE_PGID, pid);
}
-SYSCALL_DEFINE0(setsid)
+int ksys_setsid(void)
{
struct task_struct *group_leader = current->group_leader;
struct pid *sid = task_pid(group_leader);
@@ -1183,6 +1183,11 @@
return err;
}
+SYSCALL_DEFINE0(setsid)
+{
+ return ksys_setsid();
+}
+
DECLARE_RWSEM(uts_sem);
#ifdef COMPAT_UTS_MACHINE