diff --git a/kernel/scheme/sys/context.rs b/kernel/scheme/sys/context.rs
index a67b62d..26e3e2d 100644
--- a/kernel/scheme/sys/context.rs
+++ b/kernel/scheme/sys/context.rs
@@ -5,11 +5,13 @@ use context;
 use syscall::error::Result;
 
 pub fn resource() -> Result<Vec<u8>> {
-    let mut string = format!("{:<6}{:<6}{:<6}{:<6}{:<6}{:<6}{:<8}{:<6}{}\n",
+    let mut string = format!("{:<6}{:<6}{:<6}{:<6}{:<6}{:<6}{:<6}{:<6}{:<8}{:<6}{}\n",
                              "PID",
                              "PPID",
-                             "UID",
-                             "GID",
+                             "RUID",
+                             "RGID",
+                             "EUID",
+                             "EGID",
                              "STAT",
                              "CPU",
                              "MEM",
@@ -83,9 +85,11 @@ pub fn resource() -> Result<Vec<u8>> {
             let name_bytes = context.name.lock();
             let name = str::from_utf8(&name_bytes).unwrap_or("");
 
-            string.push_str(&format!("{:<6}{:<6}{:<6}{:<6}{:<6}{:<6}{:<8}{:<6}{}\n",
+            string.push_str(&format!("{:<6}{:<6}{:<6}{:<6}{:<6}{:<6}{:<6}{:<6}{:<8}{:<6}{}\n",
                                context.id.into(),
                                context.ppid.into(),
+                               context.ruid,
+                               context.rgid,
                                context.euid,
                                context.egid,
                                stat_string,
diff --git a/kernel/syscall/mod.rs b/kernel/syscall/mod.rs
index 0bb1a64..c4e30ae 100644
--- a/kernel/syscall/mod.rs
+++ b/kernel/syscall/mod.rs
@@ -86,8 +86,8 @@ pub extern fn syscall(a: usize, b: usize, c: usize, d: usize, e: usize, f: usize
                 SYS_GETGID => getgid(),
                 SYS_GETEUID => geteuid(),
                 SYS_GETEGID => getegid(),
-                SYS_SETUID => setuid(b as u32),
-                SYS_SETGID => setgid(b as u32),
+                SYS_SETREUID => setreuid(b as u32, c as u32),
+                SYS_SETREGID => setregid(b as u32, c as u32),
                 SYS_SETNS => setns(validate_slice(b as *const [usize; 2], c)?),
                 SYS_PIPE2 => pipe2(validate_slice_mut(b as *mut usize, 2)?, c),
                 SYS_PHYSALLOC => physalloc(b),
diff --git a/kernel/syscall/privilege.rs b/kernel/syscall/privilege.rs
index a4ce336..e1abd8a 100644
--- a/kernel/syscall/privilege.rs
+++ b/kernel/syscall/privilege.rs
@@ -33,26 +33,52 @@ pub fn getuid() -> Result<usize> {
     Ok(context.ruid as usize)
 }
 
-pub fn setgid(gid: u32) -> Result<usize> {
+pub fn setregid(rgid: u32, egid: u32) -> Result<usize> {
     let contexts = context::contexts();
     let context_lock = contexts.current().ok_or(Error::new(ESRCH))?;
     let mut context = context_lock.write();
-    if context.egid == 0 {
-        context.rgid = gid;
-        context.egid = gid;
+
+    if (context.euid == 0
+    || rgid as i32 == -1
+    || rgid == context.egid
+    || rgid == context.rgid)
+    && (context.euid == 0
+    || egid as i32 == -1
+    || egid == context.egid
+    || egid == context.rgid)
+    {
+        if rgid as i32 != -1 {
+            context.rgid = rgid;
+        }
+        if egid as i32 != -1 {
+            context.egid = egid;
+        }
         Ok(0)
     } else {
         Err(Error::new(EPERM))
     }
 }
 
-pub fn setuid(uid: u32) -> Result<usize> {
+pub fn setreuid(ruid: u32, euid: u32) -> Result<usize> {
     let contexts = context::contexts();
     let context_lock = contexts.current().ok_or(Error::new(ESRCH))?;
     let mut context = context_lock.write();
-    if context.euid == 0 {
-        context.ruid = uid;
-        context.euid = uid;
+
+    if (context.euid == 0
+    || ruid as i32 == -1
+    || ruid == context.euid
+    || ruid == context.ruid)
+    && (context.euid == 0
+    || euid as i32 == -1
+    || euid == context.euid
+    || euid == context.ruid)
+    {
+        if ruid as i32 != -1 {
+            context.ruid = ruid;
+        }
+        if euid as i32 != -1 {
+            context.euid = euid;
+        }
         Ok(0)
     } else {
         Err(Error::new(EPERM))
diff --git a/libstd/libc/src/syscall.rs b/libstd/libc/src/syscall.rs
index 260d030..7f44357 100644
--- a/libstd/libc/src/syscall.rs
+++ b/libstd/libc/src/syscall.rs
@@ -8,7 +8,7 @@ use self::syscall::data::{Stat, TimeSpec};
 pub use self::syscall::error::*;
 pub use self::syscall::flag::*;
 pub use self::syscall::{
-    clock_gettime, clone, execve as exec, exit, futex, getpid, kill, nanosleep, setgid, setuid, waitpid,
+    clock_gettime, clone, execve as exec, exit, futex, getpid, kill, nanosleep, setregid, setreuid, waitpid,
     chdir, chmod, getcwd, open, mkdir, rmdir, unlink, dup, pipe2,
     read, write, fcntl, fpath, fstat, fsync, ftruncate, lseek, close
 };
diff --git a/rust b/rust
index f01add1..2556400 160000
--- a/rust
+++ b/rust
@@ -1 +1 @@
-Subproject commit f01add1a3bc3d86ee62f5819fa6ed9f79d453665
+Subproject commit 2556400a5d4c9b56084332c29b6c91ac5cd3a9fa
diff --git a/syscall b/syscall
index 7b8cc59..8ce29a6 160000
--- a/syscall
+++ b/syscall
@@ -1 +1 @@
-Subproject commit 7b8cc598909189526d8c0caa8057e4a6b23f0fdc
+Subproject commit 8ce29a6ea29042d4101733cc25e84a013a74018a