From 5aebb2cdaf62c02db6dd1f0e8e19c9ec3806d221 Mon Sep 17 00:00:00 2001
From: chrchr-github <78114321+chrchr-github@users.noreply.github.com>
Date: Fri, 19 Jul 2024 10:22:38 +0200
Subject: [PATCH] Fix #12506 FP memleak when not calling freeaddrinfo() in
 error path (#6604)

---
 lib/checkleakautovar.cpp | 48 +++++++++++++++++++++++++++-------------
 test/cfg/posix.c         | 11 +++++++++
 2 files changed, 44 insertions(+), 15 deletions(-)

diff --git a/lib/checkleakautovar.cpp b/lib/checkleakautovar.cpp
index 80a3a862893..432b786edee 100644
--- a/lib/checkleakautovar.cpp
+++ b/lib/checkleakautovar.cpp
@@ -263,6 +263,30 @@ static const Token * isFunctionCall(const Token * nameToken)
     return nullptr;
 }
 
+static const Token* getOutparamAllocation(const Token* tok, const Settings& settings)
+{
+    if (!tok)
+        return nullptr;
+    int argn{};
+    const Token* ftok = getTokenArgumentFunction(tok, argn);
+    if (!ftok)
+        return nullptr;
+    if (const Library::AllocFunc* allocFunc = settings.library.getAllocFuncInfo(ftok)) {
+        if (allocFunc->arg == argn + 1)
+            return ftok;
+    }
+    return nullptr;
+}
+
+static const Token* getReturnValueFromOutparamAlloc(const Token* alloc, const Settings& settings)
+{
+    if (const Token* ftok = getOutparamAllocation(alloc, settings)) {
+        if (Token::simpleMatch(ftok->astParent()->astParent(), "="))
+            return ftok->next()->astParent()->astOperand1();
+    }
+    return nullptr;
+}
+
 bool CheckLeakAutoVar::checkScope(const Token * const startToken,
                                   VarInfo &varInfo,
                                   std::set<int> notzero,
@@ -526,6 +550,15 @@ bool CheckLeakAutoVar::checkScope(const Token * const startToken,
                         if (astIsVariableComparison(tok3, "!=", "0", &vartok) &&
                             (notzero.find(vartok->varId()) != notzero.end()))
                             varInfo2.clear();
+
+                        if (std::any_of(varInfo1.alloctype.begin(), varInfo1.alloctype.end(), [&](const std::pair<int, VarInfo::AllocInfo>& info) {
+                            if (info.second.status != VarInfo::ALLOC)
+                                return false;
+                            const Token* ret = getReturnValueFromOutparamAlloc(info.second.allocTok, *mSettings);
+                            return ret && ret->varId() && ret->varId() == vartok->varId();
+                        })) {
+                            varInfo1.clear();
+                        }
                     } else if (isVarTokComparison(tok3, &vartok, alloc_failed_conds)) {
                         varInfo1.reallocToAlloc(vartok->varId());
                         varInfo1.erase(vartok->varId());
@@ -1056,21 +1089,6 @@ void CheckLeakAutoVar::leakIfAllocated(const Token *vartok,
     }
 }
 
-static const Token* getOutparamAllocation(const Token* tok, const Settings& settings)
-{
-    if (!tok)
-        return nullptr;
-    int argn{};
-    const Token* ftok = getTokenArgumentFunction(tok, argn);
-    if (!ftok)
-        return nullptr;
-    if (const Library::AllocFunc* allocFunc = settings.library.getAllocFuncInfo(ftok)) {
-        if (allocFunc->arg == argn + 1)
-            return ftok;
-    }
-    return nullptr;
-}
-
 void CheckLeakAutoVar::ret(const Token *tok, VarInfo &varInfo, const bool isEndOfScope)
 {
     const std::map<int, VarInfo::AllocInfo> &alloctype = varInfo.alloctype;
diff --git a/test/cfg/posix.c b/test/cfg/posix.c
index b4b8c9e4985..f135ea7d6de 100644
--- a/test/cfg/posix.c
+++ b/test/cfg/posix.c
@@ -1046,6 +1046,17 @@ void memleak_getaddrinfo() // #6994
     // cppcheck-suppress memleak
 }
 
+void memleak_getaddrinfo_if() // #12506
+{
+    struct addrinfo hints = {};
+    struct addrinfo* addrs;
+    int err = getaddrinfo("example.com", "https", &hints, &addrs);
+    if (err != 0) {}
+    else {
+        freeaddrinfo(addrs);
+    }
+}
+
 void memleak_mmap(int fd)
 {
     // cppcheck-suppress [unusedAllocatedMemory, unreadVariable, constVariablePointer]