diff --git a/cfg/posix.cfg b/cfg/posix.cfg
index 92fc15c20..29bb3aef2 100644
--- a/cfg/posix.cfg
+++ b/cfg/posix.cfg
@@ -1089,6 +1089,28 @@ The function 'mktemp' is considered to be dangerous due to race conditions and s
       <not-bool/>
     </arg>
   </function>
+  <!-- int fstatat(int dirfd, const char *pathname, struct stat *statbuf, int flags); -->
+  <function name="fstat">
+    <noreturn>false</noreturn>
+    <leak-ignore/>
+    <returnValue type="int"/>
+    <arg nr="1" direction="in">
+      <not-uninit/>
+      <valid>0:</valid>
+    </arg>
+    <arg nr="2" direction="in">
+      <not-null/>
+      <not-uninit/>
+    </arg>
+    <arg nr="3" direction="out">
+      <not-null/>
+      <not-bool/>
+    </arg>
+    <arg nr="4" direction="in">
+      <not-bool/>
+      <not-uninit/>
+    </arg>
+  </function>  
   <!-- int chmod(const char *path, mode_t mode); -->
   <function name="chmod">
     <noreturn>false</noreturn>