unhide (part #3)

Stack overflow in unhide. There is a mismatch between the maxpathlen from a readlink (it gets both sizes wrong in any case).

An attack scenario might be that a rootkit is installed by an attacker then gets code execution (again presumably) when the sysadmin tries to "unhide" the rootkit.

char cmdcont[1000] ;
...
     char proc_exe[512] ;
...
      sprintf(mypath,"/proc/%d",my_pid);
      statuscmd = stat(mypath, &buffer) ;
      if ((statuscmd == 0) && S_ISDIR(buffer.st_mode))
      {
         pid_exists[N_PROC] = TRUE ;
         strcat(mypath,"/exe") ;
         length = readlink(mypath, cmdcont, 1000) ;
         if (-1 != length)
         {
            cmdcont[length] = 0;   // terminate the string
//            printf("cmdcont(proc_exe) = %s\n", cmdcont) ;   //DEBUG
            strcpy(proc_exe,cmdcont) ;
         }
         else
         {
            strcpy(proc_exe,"unknown exe") ;
         }
      }

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