sys_eval() not freeing memory and can cause crashes

[montywi]

Here is a patch to the above issues with sys_evail()

I found the issues while checking the function with valgrind.

*** org/lib_mysqludf_sys-master/lib_mysqludf_sys.c Thu Feb 21 02:39:07 2013
--- ./lib_mysqludf_sys.c Fri Jan 13 15:31:45 2023

---

*** 54,60 ****

#define LIBVERSION "lib_mysqludf_sys version 0.0.3"

! #ifdef WIN
#define SETENV(name,value) SetEnvironmentVariable(name,value);
#else
#define SETENV(name,value) setenv(name,value,1);
--- 54,60 ----

#define LIBVERSION "lib_mysqludf_sys version 0.0.3"

! #ifdef WIN64
#define SETENV(name,value) SetEnvironmentVariable(name,value);
#else
#define SETENV(name,value) setenv(name,value,1);

---

*** 373,378 ****
--- 373,380 ----
unsigned int i=0;
if(args->arg_count == 1
&& args->arg_type[i]==STRING_RESULT){

•       initid->max_length= 65535;
  

•       initid->ptr= malloc(65535);
    return 0;
  

  } else {
  strcpy(

---

*** 385,390 ****
--- 387,394 ----
void sys_eval_deinit(
UDF_INIT *initid
){

• free(initid->ptr);
• initid->ptr= 0;
  }
  char* sys_eval(
  UDF_INIT *initid

---

*** 395,424 ****
, char *error
){
FILE *pipe;
! char line[1024];
! unsigned long outlen, linelen;

! result = malloc(1);
! outlen = 0;

pipe = popen(args->args[0], "r");

while (fgets(line, sizeof(line), pipe) != NULL) {

! linelen = strlen(line);
! result = realloc(result, outlen + linelen);
! strncpy(result + outlen, line, linelen);
! outlen = outlen + linelen;
}

pclose(pipe);

! if (!(*result) || result == NULL) {
! *is_null = 1;
! } else {
! result[outlen] = 0x00;
! *length = strlen(result);
! }
!
return result;
}

--- 399,424 ----
, char *error
){
FILE *pipe;
! char line[1024], *out= result;
! unsigned long outlen;

! if (result == 0) /* Allocation failed */
! {
! *is_null = 1;
! return 0;
! }

• outlen = 0;
  pipe = popen(args->args[0], "r");

  while (fgets(line, sizeof(line), pipe) != NULL) {
  ! out= strnmov(out, line, initid->max_length - outlen);
  ! outlen = out - result;
  }

  pclose(pipe);

! *length= outlen;
return result;
}