1. 17 Oct, 2007 1 commit
  2. 17 Jul, 2007 1 commit
    • Satyam Sharma's avatar
      Introduce is_owner_or_cap() to wrap CAP_FOWNER use with fsuid check · 3bd858ab
      Satyam Sharma authored
      Introduce is_owner_or_cap() macro in fs.h, and convert over relevant
      users to it. This is done because we want to avoid bugs in the future
      where we check for only effective fsuid of the current task against a
      file's owning uid, without simultaneously checking for CAP_FOWNER as
      well, thus violating its semantics.
      [ XFS uses special macros and structures, and in general looked ...
      untouchable, so we leave it alone -- but it has been looked over. ]
      
      The (current->fsuid != inode->i_uid) check in generic_permission() and
      exec_permission_lite() is left alone, because those operations are
      covered by CAP_DAC_OVERRIDE and CAP_DAC_READ_SEARCH. Similarly operations
      falling under the purview of CAP_CHOWN and CAP_LEASE are also left alone.
      Signed-off-by: default avatarSatyam Sharma <ssatyam@cse.iitk.ac.in>
      Cc: Al Viro <viro@ftp.linux.org.uk>
      Acked-by: default avatarSerge E. Hallyn <serge@hallyn.com>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      3bd858ab
  3. 16 Jul, 2007 1 commit
  4. 08 Jul, 2007 1 commit
  5. 08 May, 2007 1 commit
    • Ulrich Drepper's avatar
      utimensat implementation · 1c710c89
      Ulrich Drepper authored
      Implement utimensat(2) which is an extension to futimesat(2) in that it
      
      a) supports nano-second resolution for the timestamps
      b) allows to selectively ignore the atime/mtime value
      c) allows to selectively use the current time for either atime or mtime
      d) supports changing the atime/mtime of a symlink itself along the lines
         of the BSD lutimes(3) functions
      
      For this change the internally used do_utimes() functions was changed to
      accept a timespec time value and an additional flags parameter.
      
      Additionally the sys_utime function was changed to match compat_sys_utime
      which already use do_utimes instead of duplicating the work.
      
      Also, the completely missing futimensat() functionality is added.  We have
      such a function in glibc but we have to resort to using /proc/self/fd/* which
      not everybody likes (chroot etc).
      
      Test application (the syscall number will need per-arch editing):
      
      #include <errno.h>
      #include <fcntl.h>
      #include <time.h>
      #include <sys/time.h>
      #include <stddef.h>
      #include <syscall.h>
      
      #define __NR_utimensat 280
      
      #define UTIME_NOW       ((1l << 30) - 1l)
      #define UTIME_OMIT      ((1l << 30) - 2l)
      
      int
      main(void)
      {
        int status = 0;
      
        int fd = open("ttt", O_RDWR|O_CREAT|O_EXCL, 0666);
        if (fd == -1)
          error (1, errno, "failed to create test file \"ttt\"");
      
        struct stat64 st1;
        if (fstat64 (fd, &st1) != 0)
          error (1, errno, "fstat failed");
      
        struct timespec t[2];
        t[0].tv_sec = 0;
        t[0].tv_nsec = 0;
        t[1].tv_sec = 0;
        t[1].tv_nsec = 0;
        if (syscall(__NR_utimensat, AT_FDCWD, "ttt", t, 0) != 0)
          error (1, errno, "utimensat failed");
      
        struct stat64 st2;
        if (fstat64 (fd, &st2) != 0)
          error (1, errno, "fstat failed");
      
        if (st2.st_atim.tv_sec != 0 || st2.st_atim.tv_nsec != 0)
          {
            puts ("atim not reset to zero");
            status = 1;
          }
        if (st2.st_mtim.tv_sec != 0 || st2.st_mtim.tv_nsec != 0)
          {
            puts ("mtim not reset to zero");
            status = 1;
          }
        if (status != 0)
          goto out;
      
        t[0] = st1.st_atim;
        t[1].tv_sec = 0;
        t[1].tv_nsec = UTIME_OMIT;
        if (syscall(__NR_utimensat, AT_FDCWD, "ttt", t, 0) != 0)
          error (1, errno, "utimensat failed");
      
        if (fstat64 (fd, &st2) != 0)
          error (1, errno, "fstat failed");
      
        if (st2.st_atim.tv_sec != st1.st_atim.tv_sec
            || st2.st_atim.tv_nsec != st1.st_atim.tv_nsec)
          {
            puts ("atim not set");
            status = 1;
          }
        if (st2.st_mtim.tv_sec != 0 || st2.st_mtim.tv_nsec != 0)
          {
            puts ("mtim changed from zero");
            status = 1;
          }
        if (status != 0)
          goto out;
      
        t[0].tv_sec = 0;
        t[0].tv_nsec = UTIME_OMIT;
        t[1] = st1.st_mtim;
        if (syscall(__NR_utimensat, AT_FDCWD, "ttt", t, 0) != 0)
          error (1, errno, "utimensat failed");
      
        if (fstat64 (fd, &st2) != 0)
          error (1, errno, "fstat failed");
      
        if (st2.st_atim.tv_sec != st1.st_atim.tv_sec
            || st2.st_atim.tv_nsec != st1.st_atim.tv_nsec)
          {
            puts ("mtim changed from original time");
            status = 1;
          }
        if (st2.st_mtim.tv_sec != st1.st_mtim.tv_sec
            || st2.st_mtim.tv_nsec != st1.st_mtim.tv_nsec)
          {
            puts ("mtim not set");
            status = 1;
          }
        if (status != 0)
          goto out;
      
        sleep (2);
      
        t[0].tv_sec = 0;
        t[0].tv_nsec = UTIME_NOW;
        t[1].tv_sec = 0;
        t[1].tv_nsec = UTIME_NOW;
        if (syscall(__NR_utimensat, AT_FDCWD, "ttt", t, 0) != 0)
          error (1, errno, "utimensat failed");
      
        if (fstat64 (fd, &st2) != 0)
          error (1, errno, "fstat failed");
      
        struct timeval tv;
        gettimeofday(&tv,NULL);
      
        if (st2.st_atim.tv_sec <= st1.st_atim.tv_sec
            || st2.st_atim.tv_sec > tv.tv_sec)
          {
            puts ("atim not set to NOW");
            status = 1;
          }
        if (st2.st_mtim.tv_sec <= st1.st_mtim.tv_sec
            || st2.st_mtim.tv_sec > tv.tv_sec)
          {
            puts ("mtim not set to NOW");
            status = 1;
          }
      
        if (symlink ("ttt", "tttsym") != 0)
          error (1, errno, "cannot create symlink");
      
        t[0].tv_sec = 0;
        t[0].tv_nsec = 0;
        t[1].tv_sec = 0;
        t[1].tv_nsec = 0;
        if (syscall(__NR_utimensat, AT_FDCWD, "tttsym", t, AT_SYMLINK_NOFOLLOW) != 0)
          error (1, errno, "utimensat failed");
      
        if (lstat64 ("tttsym", &st2) != 0)
          error (1, errno, "lstat failed");
      
        if (st2.st_atim.tv_sec != 0 || st2.st_atim.tv_nsec != 0)
          {
            puts ("symlink atim not reset to zero");
            status = 1;
          }
        if (st2.st_mtim.tv_sec != 0 || st2.st_mtim.tv_nsec != 0)
          {
            puts ("symlink mtim not reset to zero");
            status = 1;
          }
        if (status != 0)
          goto out;
      
        t[0].tv_sec = 1;
        t[0].tv_nsec = 0;
        t[1].tv_sec = 1;
        t[1].tv_nsec = 0;
        if (syscall(__NR_utimensat, fd, NULL, t, 0) != 0)
          error (1, errno, "utimensat failed");
      
        if (fstat64 (fd, &st2) != 0)
          error (1, errno, "fstat failed");
      
        if (st2.st_atim.tv_sec != 1 || st2.st_atim.tv_nsec != 0)
          {
            puts ("atim not reset to one");
            status = 1;
          }
        if (st2.st_mtim.tv_sec != 1 || st2.st_mtim.tv_nsec != 0)
          {
            puts ("mtim not reset to one");
            status = 1;
          }
      
        if (status == 0)
           puts ("all OK");
      
       out:
        close (fd);
        unlink ("ttt");
        unlink ("tttsym");
      
        return status;
      }
      
      [akpm@linux-foundation.org: add missing i386 syscall table entry]
      Signed-off-by: default avatarUlrich Drepper <drepper@redhat.com>
      Cc: Alexey Dobriyan <adobriyan@openvz.org>
      Cc: Michael Kerrisk <mtk-manpages@gmx.net>
      Cc: <linux-arch@vger.kernel.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      1c710c89
  6. 04 Dec, 2006 1 commit
  7. 01 Oct, 2006 1 commit