clang/test/Analysis/cert/env34-c-cert-examples.c

   1 // RUN: %clang_analyze_cc1                                         \
   2 // RUN:  -analyzer-checker=core,alpha.security.cert.env.InvalidPtr \
   3 // RUN:  -verify -Wno-unused %s
   4
   5 #include "../Inputs/system-header-simulator.h"
   6 char *getenv(const char *name);
   7 int strcmp(const char*, const char*);
   8 char *strdup(const char*);
   9 void free(void *memblock);
  10 void *malloc(size_t size);
  11
  12 void incorrect_usage(void) {
  13   char *tmpvar;
  14   char *tempvar;
  15
  16   tmpvar = getenv("TMP");
  17
  18   if (!tmpvar)
  19     return;
  20
  21   tempvar = getenv("TEMP");
  22
  23   if (!tempvar)
  24     return;
  25
  26   if (strcmp(tmpvar, tempvar) == 0) { // body of strcmp is unknown
  27     // expected-warning@-1{{use of invalidated pointer 'tmpvar' in a function call}}
  28   }
  29 }
  30
  31 void correct_usage_1(void) {
  32   char *tmpvar;
  33   char *tempvar;
  34
  35   const char *temp = getenv("TMP");
  36   if (temp != NULL) {
  37     tmpvar = (char *)malloc(strlen(temp)+1);
  38     if (tmpvar != NULL) {
  39       strcpy(tmpvar, temp);
  40     } else {
  41       return;
  42     }
  43   } else {
  44     return;
  45   }
  46
  47   temp = getenv("TEMP");
  48   if (temp != NULL) {
  49     tempvar = (char *)malloc(strlen(temp)+1);
  50     if (tempvar != NULL) {
  51       strcpy(tempvar, temp);
  52     } else {
  53       return;
  54     }
  55   } else {
  56     return;
  57   }
  58
  59   if (strcmp(tmpvar, tempvar) == 0) {
  60     printf("TMP and TEMP are the same.\n");
  61   } else {
  62     printf("TMP and TEMP are NOT the same.\n");
  63   }
  64   free(tmpvar);
  65   free(tempvar);
  66 }
  67
  68 void correct_usage_2(void) {
  69   char *tmpvar;
  70   char *tempvar;
  71
  72   const char *temp = getenv("TMP");
  73   if (temp != NULL) {
  74     tmpvar = strdup(temp);
  75     if (tmpvar == NULL) {
  76       return;
  77     }
  78   } else {
  79     return;
  80   }
  81
  82   temp = getenv("TEMP");
  83   if (temp != NULL) {
  84     tempvar = strdup(temp);
  85     if (tempvar == NULL) {
  86       return;
  87     }
  88   } else {
  89     return;
  90   }
  91
  92   if (strcmp(tmpvar, tempvar) == 0) {
  93     printf("TMP and TEMP are the same.\n");
  94   } else {
  95     printf("TMP and TEMP are NOT the same.\n");
  96   }
  97   free(tmpvar);
  98   tmpvar = NULL;
  99   free(tempvar);
 100   tempvar = NULL;
 101 }