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*** postfix/src/util/safe_open.c.orig	Sun Jun  4 19:04:49 2006
- --- postfix/src/util/safe_open.c	Mon Aug  4 16:47:18 2008
***************
*** 83,88 ****
- --- 83,89 ----
  #include <msg.h>
  #include <vstream.h>
  #include <vstring.h>
+ #include <stringops.h>
  #include <safe_open.h>
  
  /* safe_open_exist - open existing file */
***************
*** 138,150 ****
       * for symlinks owned by root. NEVER, NEVER, make exceptions for symlinks
       * owned by a non-root user. This would open a security hole when
       * delivering mail to a world-writable mailbox directory.
       */
      else if (lstat(path, &lstat_st) < 0) {
  	vstring_sprintf(why, "file status changed unexpectedly: %m");
  	errno = EPERM;
      } else if (S_ISLNK(lstat_st.st_mode)) {
! 	if (lstat_st.st_uid == 0)
! 	    return (fp);
  	vstring_sprintf(why, "file is a symbolic link");
  	errno = EPERM;
      } else if (fstat_st->st_dev != lstat_st.st_dev
- --- 139,167 ----
       * for symlinks owned by root. NEVER, NEVER, make exceptions for symlinks
       * owned by a non-root user. This would open a security hole when
       * delivering mail to a world-writable mailbox directory.
+      * 
+      * Sebastian Krahmer of SuSE brought to my attention that some systems have
+      * changed their semantics of link(symlink, newpath), such that the
+      * result is a hardlink to the symlink. For this reason, we now also
+      * require that the symlink's parent directory is writable only by root.
       */
      else if (lstat(path, &lstat_st) < 0) {
  	vstring_sprintf(why, "file status changed unexpectedly: %m");
  	errno = EPERM;
      } else if (S_ISLNK(lstat_st.st_mode)) {
! 	if (lstat_st.st_uid == 0) {
! 	    VSTRING *parent_buf = vstring_alloc(100);
! 	    const char *parent_path = sane_dirname(parent_buf, path);
! 	    struct stat parent_st;
! 	    int     parent_ok;
! 
! 	    parent_ok = (stat(parent_path, &parent_st) == 0	/* not lstat */
! 			 && parent_st.st_uid == 0
! 			 && (parent_st.st_mode & (S_IWGRP | S_IWOTH)) == 0);
! 	    vstring_free(parent_buf);
! 	    if (parent_ok)
! 		return (fp);
! 	}
  	vstring_sprintf(why, "file is a symbolic link");
  	errno = EPERM;
      } else if (fstat_st->st_dev != lstat_st.st_dev