diff --git a/cfg/posix.cfg b/cfg/posix.cfg
index cce1045b3..32bede511 100644
--- a/cfg/posix.cfg
+++ b/cfg/posix.cfg
@@ -3970,6 +3970,46 @@ The function 'mktemp' is considered to be dangerous due to race conditions and s
       <not-bool/>
     </arg>
   </function>
+<!-- https://man7.org/linux/man-pages/man3/gethostbyaddr_r.3.html -->
+<!-- int gethostbyaddr_r(const void *addr, socklen_t len, int type, struct hostent *restrict ret, char *restrict buf, size_t buflen, struct hostent **restrict result, int *restrict h_errnop); -->
+<function name="gethostbyaddr_r">
+  <returnValue type="int"/>
+  <noreturn>false</noreturn>
+  <use-retval/>
+  <pure/>
+  <arg nr="1" direction="in">
+    <not-uninit/>
+    <not-null/>
+  </arg>
+  <arg nr="2" direction="in">
+    <not-uninit/>
+    <valid>0:</valid>
+  </arg>
+  <arg nr="3" direction="in">
+    <not-uninit/>
+  </arg>
+  <arg nr="4" direction="out">
+    <not-null/>
+  </arg>
+  <arg nr="5" direction="in">
+    <not-uninit/>
+    <not-null/>
+    <minsize type="argvalue" arg="6"/>
+  </arg>
+  <arg nr="6" direction="in">
+    <not-uninit/>
+    <valid>0:</valid>
+  </arg>
+  <arg nr="7" direction="in">
+    <not-null/>
+    <not-uninit/>
+  </arg>
+  <arg nr="8" direction="in">
+    <not-null/>
+    <not-uninit/>
+  </arg>
+</function>
+
   <!-- void setkey(const char *key); -->
   <function name="setkey">
     <noreturn>false</noreturn>
diff --git a/test/cfg/gnu.c b/test/cfg/gnu.c
index 3a909dc2f..6f2f7be6c 100644
--- a/test/cfg/gnu.c
+++ b/test/cfg/gnu.c
@@ -34,6 +34,21 @@ void unreachableCode_error(void) // #11197
     int i;
 }
 
+int nullPointer_gethostbyaddr_r(const void* addr, socklen_t len, int type, struct hostent* ret, char* buf, size_t buflen, struct hostent** result, int* h_errnop)
+{
+    // cppcheck-suppress nullPointer
+    (void) gethostbyaddr_r(NULL, len, type, ret, buf, buflen, result, h_errnop);
+    // cppcheck-suppress nullPointer
+    (void) gethostbyaddr_r(addr, len, type, NULL, buf, buflen, result, h_errnop);
+    // cppcheck-suppress nullPointer
+    (void) gethostbyaddr_r(addr, len, type, ret, NULL, buflen, result, h_errnop);
+    // cppcheck-suppress nullPointer
+    (void) gethostbyaddr_r(addr, len, type, ret, buf, buflen, NULL, h_errnop);
+    // cppcheck-suppress nullPointer
+    (void) gethostbyaddr_r(addr, len, type, ret, buf, buflen, result, NULL);
+    return gethostbyaddr_r(addr, len, type, ret, buf, buflen, result, h_errnop);
+}
+
 int nullPointer_getopt_long(int argc, char **argv, const char *optstring,
                             const struct option *longopts, int *longindex)
 {