alpine 3.6
access weakness #263

1

Weakness Breakdown


Definition:

An access weakness occurs when software does not properly implement permissions that could have unintended consequences if exploited by malicious actors. An example of this weakness is when a default username and password are set by the developer but do not get changed by the system administrator.

Warning code(s):

Ensure that umask is given most restrictive possible setting.

File Name:

s6/src/s6-2.5.1.0/src/libs6/ftrigw_fifodir_make.c

Context:

The highlighted line of code below is the trigger point of this particular Alpine 3.6 access weakness.

 /* ISC license. */

#include <sys/stat.h>
#include <unistd.h>
#include <errno.h>
#include <s6/ftrigw.h>

int ftrigw_fifodir_make (char const *path, gid_t gid, int force)
{
  mode_t m = umask(0) ;
  if (mkdir(path, 0700) == -1)
  {
    struct stat st ;
    umask(m) ;
    if (errno != EEXIST) return 0 ;
    if (stat(path, &st) == -1) return 0 ;
    if (st.st_uid != getuid()) return (errno = EACCES, 0) ;
    if (!S_ISDIR(st.st_mode)) return (errno = ENOTDIR, 0) ;
    if (!force) return 1 ;
  }
  else umask(m) ;
  if ((gid >= 0) && (chown(path, -1, gid) == -1)) return 0 ;
  if (chmod(path, (gid >= 0) ? 03730 : 01733) == -1) return 0 ;
  return 1 ;
} 

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