From e21def2aea233d2486862f70419db9bd2ba0c01c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Martin=20V=C3=ADtek?= <martinv@students.zcu.cz>
Date: Sat, 26 Sep 2020 18:00:29 +0200
Subject: [PATCH 1/2] Fixed memory leak in
 nfc_initiator_select_passive_target()

---
 libnfc/nfc.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/libnfc/nfc.c b/libnfc/nfc.c
index 6f58a71..d89f0f0 100644
--- a/libnfc/nfc.c
+++ b/libnfc/nfc.c
@@ -579,6 +579,7 @@ nfc_initiator_select_passive_target(nfc_device *pnd,
     free(abtTmpInit);
   } else if (nm.nmt == NMT_ISO14443A) {
     abtInit = abtTmpInit;
+    free(abtTmpInit);
     iso14443_cascade_uid(pbtInitData, szInitData, abtInit, &szInit);
   } else {
     abtInit = abtTmpInit;
@@ -587,8 +588,6 @@ nfc_initiator_select_passive_target(nfc_device *pnd,
     szInit = szInitData;
   }
   HAL(initiator_select_passive_target, pnd, nm, abtInit, szInit, pnt);
-
-  free(abtTmpInit);
 }
 
 /** @ingroup initiator

From 3434adbb4e8c605545ba89dd817d693cc0cbd1b8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Martin=20V=C3=ADtek?= <martinv@rice.zcu.cz>
Date: Fri, 16 Oct 2020 14:52:16 +0200
Subject: [PATCH 2/2] Replaced malloc() with alloca()

---
 libnfc/nfc.c | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/libnfc/nfc.c b/libnfc/nfc.c
index d89f0f0..419dbde 100644
--- a/libnfc/nfc.c
+++ b/libnfc/nfc.c
@@ -81,6 +81,7 @@
 #include <stddef.h>
 #include <string.h>
 #include <assert.h>
+#include <alloca.h>
 
 #include <nfc/nfc.h>
 
@@ -566,25 +567,21 @@ nfc_initiator_select_passive_target(nfc_device *pnd,
 {
   uint8_t *abtInit = NULL;
   uint8_t maxAbt = MAX(12, szInitData);
-  uint8_t *abtTmpInit = malloc(sizeof(uint8_t) * maxAbt);
+  uint8_t *abtTmpInit = alloca(sizeof(uint8_t) * maxAbt);
   size_t  szInit = 0;
   int res;
   if ((res = nfc_device_validate_modulation(pnd, N_INITIATOR, &nm)) != NFC_SUCCESS) {
-    free(abtTmpInit);
     return res;
   }
   if (szInitData == 0) {
     // Provide default values, if any
     prepare_initiator_data(nm, &abtInit, &szInit);
-    free(abtTmpInit);
   } else if (nm.nmt == NMT_ISO14443A) {
     abtInit = abtTmpInit;
-    free(abtTmpInit);
     iso14443_cascade_uid(pbtInitData, szInitData, abtInit, &szInit);
   } else {
     abtInit = abtTmpInit;
     memcpy(abtInit, pbtInitData, szInitData);
-    free(abtTmpInit);
     szInit = szInitData;
   }
   HAL(initiator_select_passive_target, pnd, nm, abtInit, szInit, pnt);