[MESOS-2412] Potential memleak(s) in stout/os.hpp

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.23.0
• Component/s: stout
• Labels: coverity mesosphere twitter
• Target Version/s: 0.23.0
• Sprint: Mesosphere Q1 Sprint 4 - 3/6
• Assignee: Jörg Schad
• Reporter: Jörg Schad
• Shepherd: Till Toenshoff
• Created: 26/Feb/15 09:47
• Updated: 26/Nov/18 12:22
• Resolved: 26/Nov/18 12:22

Description

Coverity picked up this potential memleak in os.hpp where we do not delete buffer in the else case. The exact same pattern occurs in getuid(const Option<std::string>& user = None()).
The corresponding CID 1230371 and 1230371.

inline Result<gid_t> getgid(const Option<std::string>& user = None())
...
  while (true) {
    char* buffer = new char[size];

    if (getpwnam_r(user.get().c_str(), &passwd, buffer, size, &result) == 0) {
      ... 
      delete[] buffer;
      return gid;
    } else {
      // RHEL7 (and possibly other systems) will return non-zero and
      // set one of the following errors for "The given name or uid
      // was not found." See 'man getpwnam_r'. We only check for the
      // errors explicitly listed, and do not consider the ellipsis.
      if (errno == ENOENT ||
          errno == ESRCH ||
          errno == EBADF ||
          errno == EPERM) {
        return None();
       // HERE WE DO NOT DELETE BUFFER.
      }
     ...
     // getpwnam_r set ERANGE so try again with a larger buffer.
      size *= 2;
      delete[] buffer;
   }

Issue Links

• is related to: MESOS-2418 Remove raw pointers from stout/os.hpp
• is related to: MESOS-2569 Introduce Buffer abstraction to minimize inline buffer size constants, allocation and safe-guards