diff --git a/cfg/posix.cfg b/cfg/posix.cfg
index 35a2dd777..860a512c2 100644
--- a/cfg/posix.cfg
+++ b/cfg/posix.cfg
@@ -3396,17 +3396,21 @@ The function 'mktemp' is considered to be dangerous due to race conditions and s
     </arg>
     <warn severity="portability">Non reentrant function 'getpwuid' called. For threadsafe applications it is recommended to use the reentrant replacement function 'getpwuid_r'.</warn>
   </function>
-  <!-- https://pubs.opengroup.org/onlinepubs/9699919799/functions/getpwuid.html -->
-  <!-- int getpwuid_r(uid_t uid, struct passwd *pwd, char *buffer, size_t bufsize, struct passwd **result); -->
+  <!-- https://man7.org/linux/man-pages/man3/getpwnam.3.html -->
+  <!-- int getpwuid_r(uid_t uid, struct passwd *restrict pwd, char *restrict buf, size_t buflen, struct passwd **restrict result) -->
   <function name="getpwuid_r">
     <returnValue type="int"/>
+    <use-retval/>
     <noreturn>false</noreturn>
     <arg nr="1" direction="in">
       <not-uninit/>
       <not-bool/>
     </arg>
-    <arg nr="2" direction="out"/>
+    <arg nr="2" direction="out">
+      <not-null/>
+    </arg>
     <arg nr="3" direction="out">
+      <not-null/>
       <minsize type="argvalue" arg="4"/>
     </arg>
     <arg nr="4" direction="in">
@@ -3416,6 +3420,7 @@ The function 'mktemp' is considered to be dangerous due to race conditions and s
     </arg>
     <arg nr="5" direction="out">
       <not-bool/>
+      <not-null/>
     </arg>
   </function>
   <!-- void setpwent(void); -->
diff --git a/test/cfg/posix.c b/test/cfg/posix.c
index f735a4b5c..482214d12 100644
--- a/test/cfg/posix.c
+++ b/test/cfg/posix.c
@@ -35,6 +35,17 @@
 #include <string.h>
 #include <strings.h>
 
+int nullPointer_getpwuid_r(uid_t uid, struct passwd *pwd, char *buffer, size_t bufsize, struct passwd **result)
+{
+    // cppcheck-suppress nullPointer
+    (void) getpwuid_r(uid, NULL, buffer, bufsize, result);
+    // cppcheck-suppress nullPointer
+    (void) getpwuid_r(uid, pwd, NULL, bufsize, result);
+    // cppcheck-suppress nullPointer
+    (void) getpwuid_r(uid, pwd, buffer, bufsize, NULL);
+    return getpwuid_r(uid, pwd, buffer, bufsize, result);
+}
+
 int nullPointer_getpwnam_r(const char *name, struct passwd *pwd, char *buffer, size_t bufsize, struct passwd **result)
 {
     // cppcheck-suppress nullPointer