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

   1 // Default options.
   2 // RUN: %clang_analyze_cc1                                                      \
   3 // RUN:  -analyzer-checker=core,security.cert.env.InvalidPtr                    \
   4 // RUN:  -verify -Wno-unused %s
   5 //
   6 // Test the laxer handling of getenv function (this is the default).
   7 // RUN: %clang_analyze_cc1                                                      \
   8 // RUN:  -analyzer-checker=core,security.cert.env.InvalidPtr                    \
   9 // RUN:  -analyzer-config security.cert.env.InvalidPtr:InvalidatingGetEnv=false \
  10 // RUN:  -verify -Wno-unused %s
  11 //
  12 // Test the stricter handling of getenv function.
  13 // RUN: %clang_analyze_cc1                                                      \
  14 // RUN:  -analyzer-checker=core,security.cert.env.InvalidPtr                    \
  15 // RUN:  -analyzer-config security.cert.env.InvalidPtr:InvalidatingGetEnv=true  \
  16 // RUN:  -verify=expected,pedantic -Wno-unused %s
  17
  18 #include "../Inputs/system-header-simulator.h"
  19 char *getenv(const char *name);
  20 int setenv(const char *name, const char *value, int overwrite);
  21 int strcmp(const char*, const char*);
  22 char *strdup(const char*);
  23 void free(void *memblock);
  24 void *malloc(size_t size);
  25
  26 void incorrect_usage_setenv_getenv_invalidation(void) {
  27   char *tmpvar;
  28   char *tempvar;
  29
  30   tmpvar = getenv("TMP");
  31
  32   if (!tmpvar)
  33     return;
  34
  35   setenv("TEMP", "", 1); //setenv can invalidate env
  36
  37   if (!tmpvar)
  38     return;
  39
  40   if (strcmp(tmpvar, "") == 0) { // body of strcmp is unknown
  41     // expected-warning@-1{{use of invalidated pointer 'tmpvar' in a function call}}
  42   }
  43 }
  44
  45 void incorrect_usage_double_getenv_invalidation(void) {
  46   char *tmpvar;
  47   char *tempvar;
  48
  49   tmpvar = getenv("TMP");
  50
  51   if (!tmpvar)
  52     return;
  53
  54   tempvar = getenv("TEMP"); //getenv should not invalidate env in non-pedantic mode
  55
  56   if (!tempvar)
  57     return;
  58
  59   if (strcmp(tmpvar, tempvar) == 0) { // body of strcmp is unknown
  60     // pedantic-warning@-1{{use of invalidated pointer 'tmpvar' in a function call}}
  61   }
  62 }
  63
  64 void correct_usage_1(void) {
  65   char *tmpvar;
  66   char *tempvar;
  67
  68   const char *temp = getenv("TMP");
  69   if (temp != NULL) {
  70     tmpvar = (char *)malloc(strlen(temp)+1);
  71     if (tmpvar != NULL) {
  72       strcpy(tmpvar, temp);
  73     } else {
  74       return;
  75     }
  76   } else {
  77     return;
  78   }
  79
  80   temp = getenv("TEMP");
  81   if (temp != NULL) {
  82     tempvar = (char *)malloc(strlen(temp)+1);
  83     if (tempvar != NULL) {
  84       strcpy(tempvar, temp);
  85     } else {
  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   free(tempvar);
  99 }
 100
 101 void correct_usage_2(void) {
 102   char *tmpvar;
 103   char *tempvar;
 104
 105   const char *temp = getenv("TMP");
 106   if (temp != NULL) {
 107     tmpvar = strdup(temp);
 108     if (tmpvar == NULL) {
 109       return;
 110     }
 111   } else {
 112     return;
 113   }
 114
 115   temp = getenv("TEMP");
 116   if (temp != NULL) {
 117     tempvar = strdup(temp);
 118     if (tempvar == NULL) {
 119       return;
 120     }
 121   } else {
 122     return;
 123   }
 124
 125   if (strcmp(tmpvar, tempvar) == 0) {
 126     printf("TMP and TEMP are the same.\n");
 127   } else {
 128     printf("TMP and TEMP are NOT the same.\n");
 129   }
 130   free(tmpvar);
 131   tmpvar = NULL;
 132   free(tempvar);
 133   tempvar = NULL;
 134 }