From 3a5793be4fb040709a115d44d969364b61a4fd06 Mon Sep 17 00:00:00 2001
From: He Sun <bochang.sh@antfin.com>
Date: Wed, 17 Jun 2020 07:44:47 +0800
Subject: [PATCH] Fix set_tid_address not supporting null pointers

---
 src/libos/src/process/syscalls.rs | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/libos/src/process/syscalls.rs b/src/libos/src/process/syscalls.rs
index ea20cd17..1ca946d2 100644
--- a/src/libos/src/process/syscalls.rs
+++ b/src/libos/src/process/syscalls.rs
@@ -180,7 +180,9 @@ pub fn do_arch_prctl(code: u32, addr: *mut usize) -> Result<isize> {
 }
 
 pub fn do_set_tid_address(tidptr: *mut pid_t) -> Result<isize> {
-    check_mut_ptr(tidptr)?;
+    if !tidptr.is_null() {
+        check_mut_ptr(tidptr)?;
+    }
     super::do_set_tid_address::do_set_tid_address(tidptr).map(|tid| tid as isize)
 }