From https://ftp.gnu.org/gnu/bash/bash-4.4-patches/bash44-007

Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

			     BASH PATCH REPORT
			     =================

Bash-Release:	4.4
Patch-ID:	bash44-007

Bug-Reported-by:	Jens Heyens <jens.heyens@cispa.saarland>
Bug-Reference-ID:	
Bug-Reference-URL:	https://savannah.gnu.org/support/?109224

Bug-Description:

When performing filename completion, bash dequotes the directory name being
completed, which can result in match failures and potential unwanted
expansion.

Patch (apply with `patch -p0'):

*** bash-4.4-patched/bashline.c	2016-08-05 21:44:05.000000000 -0400
--- b/bashline.c	2017-01-19 13:15:51.000000000 -0500
***************
*** 143,147 ****
  static void restore_directory_hook __P((rl_icppfunc_t));
  
! static int directory_exists __P((const char *));
  
  static void cleanup_expansion_error __P((void));
--- b/144,148 ----
  static void restore_directory_hook __P((rl_icppfunc_t));
  
! static int directory_exists __P((const char *, int));
  
  static void cleanup_expansion_error __P((void));
***************
*** 3103,3111 ****
  }
  
! /* Check whether not the (dequoted) version of DIRNAME, with any trailing slash
!    removed, exists. */
  static int
! directory_exists (dirname)
       const char *dirname;
  {
    char *new_dirname;
--- b/3107,3116 ----
  }
  
! /* Check whether not DIRNAME, with any trailing slash removed, exists.  If
!    SHOULD_DEQUOTE is non-zero, we dequote the directory name first. */
  static int
! directory_exists (dirname, should_dequote)
       const char *dirname;
+      int should_dequote;
  {
    char *new_dirname;
***************
*** 3113,3118 ****
    struct stat sb;
  
!   /* First, dequote the directory name */
!   new_dirname = bash_dequote_filename ((char *)dirname, rl_completion_quote_character);
    dirlen = STRLEN (new_dirname);
    if (new_dirname[dirlen - 1] == '/')
--- b/3118,3124 ----
    struct stat sb;
  
!   /* We save the string and chop the trailing slash because stat/lstat behave
!      inconsistently if one is present. */
!   new_dirname = should_dequote ? bash_dequote_filename ((char *)dirname, rl_completion_quote_character) : savestring (dirname);
    dirlen = STRLEN (new_dirname);
    if (new_dirname[dirlen - 1] == '/')
***************
*** 3146,3150 ****
      should_expand_dirname = '`';
  
!   if (should_expand_dirname && directory_exists (local_dirname))
      should_expand_dirname = 0;
    
--- b/3152,3156 ----
      should_expand_dirname = '`';
  
!   if (should_expand_dirname && directory_exists (local_dirname, 0))
      should_expand_dirname = 0;
    
***************
*** 3156,3160 ****
        global_nounset = unbound_vars_is_error;
        unbound_vars_is_error = 0;
!       wl = expand_prompt_string (new_dirname, 0, W_NOCOMSUB|W_COMPLETE);	/* does the right thing */
        unbound_vars_is_error = global_nounset;
        if (wl)
--- b/3162,3166 ----
        global_nounset = unbound_vars_is_error;
        unbound_vars_is_error = 0;
!       wl = expand_prompt_string (new_dirname, 0, W_NOCOMSUB|W_NOPROCSUB|W_COMPLETE);	/* does the right thing */
        unbound_vars_is_error = global_nounset;
        if (wl)
***************
*** 3245,3249 ****
      }
  
!   if (should_expand_dirname && directory_exists (local_dirname))
      should_expand_dirname = 0;
  
--- b/3262,3266 ----
      }
  
!   if (should_expand_dirname && directory_exists (local_dirname, 1))
      should_expand_dirname = 0;
  
***************
*** 3251,3255 ****
      {
        new_dirname = savestring (local_dirname);
!       wl = expand_prompt_string (new_dirname, 0, W_NOCOMSUB|W_COMPLETE);	/* does the right thing */
        if (wl)
  	{
--- b/3268,3272 ----
      {
        new_dirname = savestring (local_dirname);
!       wl = expand_prompt_string (new_dirname, 0, W_NOCOMSUB|W_NOPROCSUB|W_COMPLETE);	/* does the right thing */
        if (wl)
  	{
*** bash-4.4/subst.c	2016-08-30 16:46:38.000000000 -0400
--- b/subst.c	2017-01-19 07:09:57.000000000 -0500
***************
*** 9459,9462 ****
--- b/9459,9466 ----
  	      if (word->flags & W_COMPLETE)
  		tword->flags |= W_COMPLETE;	/* for command substitutions */
+ 	      if (word->flags & W_NOCOMSUB)
+ 		tword->flags |= W_NOCOMSUB;
+ 	      if (word->flags & W_NOPROCSUB)
+ 		tword->flags |= W_NOPROCSUB;
  
  	      temp = (char *)NULL;
*** bash-4.4/patchlevel.h	2016-06-22 14:51:03.000000000 -0400
--- b/patchlevel.h	2016-10-01 11:01:28.000000000 -0400
***************
*** 26,30 ****
     looks for to find the patch level (for the sccs version string). */
  
! #define PATCHLEVEL 6
  
  #endif /* _PATCHLEVEL_H_ */
--- b/26,30 ----
     looks for to find the patch level (for the sccs version string). */
  
! #define PATCHLEVEL 7
  
  #endif /* _PATCHLEVEL_H_ */