diff --git a/cfg/cppcheck-cfg.rng b/cfg/cppcheck-cfg.rng
index b87c07152..a6dba3351 100644
--- a/cfg/cppcheck-cfg.rng
+++ b/cfg/cppcheck-cfg.rng
@@ -474,11 +474,9 @@
   </define>
 
   <define name="DATA-BUFFER-SIZE">
-    <choice>
-      <value>malloc</value>
-      <value>calloc</value>
-      <value>strdup</value>
-    </choice>
+    <data type="string">
+      <param name="pattern">malloc(:[1-5])?|calloc(:[1-5],[1-5])?|strdup(:[1-5])?</param>
+    </data>
   </define>
 
   <define name="CONTAINER-ACTION">
diff --git a/lib/library.cpp b/lib/library.cpp
index 181d00294..53f4187cd 100644
--- a/lib/library.cpp
+++ b/lib/library.cpp
@@ -204,14 +204,25 @@ Library::Error Library::load(const tinyxml2::XMLDocument &doc)
                     const char *bufferSize = memorynode->Attribute("buffer-size");
                     if (!bufferSize)
                         temp.bufferSize = AllocFunc::BufferSize::none;
-                    else if (std::strcmp(bufferSize, "malloc") == 0)
-                        temp.bufferSize = AllocFunc::BufferSize::malloc;
-                    else if (std::strcmp(bufferSize, "calloc") == 0)
-                        temp.bufferSize = AllocFunc::BufferSize::calloc;
-                    else if (std::strcmp(bufferSize, "strdup") == 0)
-                        temp.bufferSize = AllocFunc::BufferSize::strdup;
-                    else
-                        return Error(BAD_ATTRIBUTE_VALUE, bufferSize);
+                    else {
+                        if (std::strncmp(bufferSize, "malloc", 6) == 0)
+                            temp.bufferSize = AllocFunc::BufferSize::malloc;
+                        else if (std::strncmp(bufferSize, "calloc", 6) == 0)
+                            temp.bufferSize = AllocFunc::BufferSize::calloc;
+                        else if (std::strncmp(bufferSize, "strdup", 6) == 0)
+                            temp.bufferSize = AllocFunc::BufferSize::strdup;
+                        else
+                            return Error(BAD_ATTRIBUTE_VALUE, bufferSize);
+                        if (bufferSize[6] == 0) {
+                            temp.bufferSizeArg1 = 1;
+                            temp.bufferSizeArg2 = 2;
+                        } else if (bufferSize[6] == ':' && bufferSize[7] >= '1' && bufferSize[7] <= '5') {
+                            temp.bufferSizeArg1 = bufferSize[7] - '0';
+                            if (bufferSize[8] == ',' && bufferSize[9] >= '1' && bufferSize[9] <= '5')
+                                temp.bufferSizeArg2 = bufferSize[9] - '0';
+                        } else
+                            return Error(BAD_ATTRIBUTE_VALUE, bufferSize);
+                    }
 
                     mAlloc[memorynode->GetText()] = temp;
                 } else if (memorynodename == "dealloc") {
diff --git a/lib/library.h b/lib/library.h
index 204bebb7e..315215f1a 100644
--- a/lib/library.h
+++ b/lib/library.h
@@ -75,6 +75,8 @@ public:
         int arg;
         enum class BufferSize {none,malloc,calloc,strdup};
         BufferSize bufferSize;
+        int bufferSizeArg1;
+        int bufferSizeArg2;
     };
 
     /** get allocation info for function */
diff --git a/lib/valueflow.cpp b/lib/valueflow.cpp
index 6d35dce33..49bc3611c 100644
--- a/lib/valueflow.cpp
+++ b/lib/valueflow.cpp
@@ -5130,21 +5130,24 @@ static void valueFlowDynamicBufferSize(TokenList *tokenlist, SymbolDatabase *sym
 
             const std::vector<const Token *> args = getArguments(rhs->previous());
 
+            const Token * const arg1 = (args.size() >= allocFunc->bufferSizeArg1) ? args[allocFunc->bufferSizeArg1 - 1] : nullptr;
+            const Token * const arg2 = (args.size() >= allocFunc->bufferSizeArg2) ? args[allocFunc->bufferSizeArg2 - 1] : nullptr;
+
             MathLib::bigint sizeValue = -1;
             switch (allocFunc->bufferSize) {
             case Library::AllocFunc::BufferSize::none:
                 break;
             case Library::AllocFunc::BufferSize::malloc:
-                if (args.size() == 1 && args[0]->hasKnownIntValue())
-                    sizeValue = args[0]->getKnownIntValue();
+                if (arg1 && arg1->hasKnownIntValue())
+                    sizeValue = arg1->getKnownIntValue();
                 break;
             case Library::AllocFunc::BufferSize::calloc:
-                if (args.size() == 2 && args[0]->hasKnownIntValue() && args[1]->hasKnownIntValue())
-                    sizeValue = args[0]->getKnownIntValue() * args[1]->getKnownIntValue();
+                if (arg1 && arg2 && arg1->hasKnownIntValue() && arg2->hasKnownIntValue())
+                    sizeValue = arg1->getKnownIntValue() * arg2->getKnownIntValue();
                 break;
             case Library::AllocFunc::BufferSize::strdup:
-                if (args.size() == 1 && args[0]->hasKnownValue()) {
-                    const ValueFlow::Value &value = args[0]->values().back();
+                if (arg1 && arg1->hasKnownValue()) {
+                    const ValueFlow::Value &value = arg1->values().back();
                     if (value.isTokValue() && value.tokvalue->tokType() == Token::eString)
                         sizeValue = Token::getStrLength(value.tokvalue);
                 }