4 files changed, 20 insertions, 1 deletions
diff --git a/sys/include/sys/syscall.h b/sys/include/sys/syscall.h
index 3650e7a..05288f4 100644
--- a/sys/include/sys/syscall.h
+++ b/sys/include/sys/syscall.h
@@ -56,6 +56,7 @@
 #define SYS_inject  15
 #define SYS_getpid  16
 #define SYS_getppid 17
+#define SYS_setuid  18
 
 #if defined(_KERNEL)
 /* Syscall return value and arg type */
diff --git a/sys/include/sys/ucred.h b/sys/include/sys/ucred.h
index ef66a18..b44a7fe 100644
--- a/sys/include/sys/ucred.h
+++ b/sys/include/sys/ucred.h
@@ -33,6 +33,7 @@
 #include <sys/types.h>
 #if defined(_KERNEL)
 #include <sys/spinlock.h>
+#include <sys/syscall.h>
 #endif
 
 /*
@@ -47,4 +48,8 @@ struct ucred {
 };
 
 int setuid(uid_t new);
+
+#if defined(_KERNEL)
+scret_t sys_setuid(struct syscall_args *scargs);
+#endif
 #endif  /* !_SYS_UCRED_H_ */
diff --git a/sys/kern/kern_cred.c b/sys/kern/kern_cred.c
index 828ba3b..e1202fc 100644
--- a/sys/kern/kern_cred.c
+++ b/sys/kern/kern_cred.c
@@ -55,3 +55,14 @@ setuid(uid_t new)
     spinlock_release(&cur_cred->lock);
     return 0;
 }
+
+/*
+ * setuid() syscall
+ *
+ * arg0: `new'
+ */
+scret_t
+sys_setuid(struct syscall_args *scargs)
+{
+    return setuid(scargs->arg0);
+}
diff --git a/sys/kern/kern_syscall.c b/sys/kern/kern_syscall.c
index 739dd7f..276c7c7 100644
--- a/sys/kern/kern_syscall.c
+++ b/sys/kern/kern_syscall.c
@@ -31,6 +31,7 @@
 #include <sys/sysctl.h>
 #include <sys/reboot.h>
 #include <sys/types.h>
+#include <sys/ucred.h>
 #include <sys/time.h>
 #include <sys/mman.h>
 #include <sys/proc.h>
@@ -55,7 +56,8 @@ scret_t(*g_sctab[])(struct syscall_args *) = {
     sys_sleep,  /* SYS_sleep */
     sys_inject, /* SYS_inject */
     sys_getpid, /* SYS_getpid */
-    sys_getppid /* SYS_getppid */
+    sys_getppid, /* SYS_getppid */
+    sys_setuid,  /* SYS_setuid */
 };
 
 const size_t MAX_SYSCALLS = NELEM(g_sctab);