1 /* Check for GLOB_TIDLE heap allocation issues (bugs 22320, 22325, 22332).
2    Copyright (C) 2017-2022 Free Software Foundation, Inc.
3    This file is part of the GNU C Library.
4 
5    The GNU C Library is free software; you can redistribute it and/or
6    modify it under the terms of the GNU Lesser General Public
7    License as published by the Free Software Foundation; either
8    version 2.1 of the License, or (at your option) any later version.
9 
10    The GNU C Library is distributed in the hope that it will be useful,
11    but WITHOUT ANY WARRANTY; without even the implied warranty of
12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13    Lesser General Public License for more details.
14 
15    You should have received a copy of the GNU Lesser General Public
16    License along with the GNU C Library; if not, see
17    <https://www.gnu.org/licenses/>.  */
18 
19 #include <glob.h>
20 #include <mcheck.h>
21 #include <nss.h>
22 #include <pwd.h>
23 #include <stdlib.h>
24 #include <string.h>
25 #include <support/check.h>
26 #include <support/support.h>
27 
28 /* Flag which indicates whether to pass the GLOB_ONLYDIR flag.  */
29 static int do_onlydir;
30 
31 /* Flag which indicates whether to pass the GLOB_NOCHECK flag.  */
32 static int do_nocheck;
33 
34 /* Flag which indicates whether to pass the GLOB_MARK flag.  */
35 static int do_mark;
36 
37 /* Flag which indicates whether to pass the GLOB_NOESCAPE flag.  */
38 static int do_noescape;
39 
40 static void
one_test(const char * prefix,const char * middle,const char * suffix)41 one_test (const char *prefix, const char *middle, const char *suffix)
42 {
43   char *pattern = xasprintf ("%s%s%s", prefix, middle, suffix);
44   int flags = GLOB_TILDE;
45   if (do_onlydir)
46     flags |= GLOB_ONLYDIR;
47   if (do_nocheck)
48     flags |= GLOB_NOCHECK;
49   if (do_mark)
50     flags |= GLOB_MARK;
51   if (do_noescape)
52     flags |= GLOB_NOESCAPE;
53   glob_t gl;
54   /* This glob call might result in crashes or memory leaks.  */
55   if (glob (pattern, flags, NULL, &gl) == 0)
56     globfree (&gl);
57   free (pattern);
58 }
59 
60 enum
61   {
62     /* The largest base being tested.  */
63     largest_base_size = 500000,
64 
65     /* The actual size is the base size plus a variable whose absolute
66        value is not greater than this.  This helps malloc to trigger
67        overflows.  */
68     max_size_skew = 16,
69 
70     /* The maximum string length supported by repeating_string
71        below.  */
72     repeat_size = largest_base_size + max_size_skew,
73   };
74 
75 /* Used to construct strings which repeat a single character 'x'.  */
76 static char *repeat;
77 
78 /* Return a string of SIZE characters.  */
79 const char *
repeating_string(int size)80 repeating_string (int size)
81 {
82   TEST_VERIFY (size >= 0);
83   TEST_VERIFY (size <= repeat_size);
84   const char *repeated_shifted = repeat + repeat_size - size;
85   TEST_VERIFY (strlen (repeated_shifted) == size);
86   return repeated_shifted;
87 }
88 
89 static int
do_test(void)90 do_test (void)
91 {
92   /* Avoid network-based NSS modules and initialize nss_files with a
93      dummy lookup.  This has to come before mtrace because NSS does
94      not free all memory.  */
95   __nss_configure_lookup ("passwd", "files");
96   (void) getpwnam ("root");
97 
98   mtrace ();
99 
100   repeat = xmalloc (repeat_size + 1);
101   memset (repeat, 'x', repeat_size);
102   repeat[repeat_size] = '\0';
103 
104   /* These numbers control the size of the user name.  The values
105      cover the minimum (0), a typical size (8), a large
106      stack-allocated size (100000), and a somewhat large
107      heap-allocated size (largest_base_size).  */
108   static const int base_sizes[] = { 0, 8, 100, 100000, largest_base_size, -1 };
109 
110   for (do_onlydir = 0; do_onlydir < 2; ++do_onlydir)
111     for (do_nocheck = 0; do_nocheck < 2; ++do_nocheck)
112       for (do_mark = 0; do_mark < 2; ++do_mark)
113 	for (do_noescape = 0; do_noescape < 2; ++do_noescape)
114 	  for (int base_idx = 0; base_sizes[base_idx] >= 0; ++base_idx)
115 	    {
116 	      for (int size_skew = -max_size_skew; size_skew <= max_size_skew;
117 		   ++size_skew)
118 		{
119 		  int size = base_sizes[base_idx] + size_skew;
120 		  if (size < 0)
121 		    continue;
122 
123 		  const char *user_name = repeating_string (size);
124 		  one_test ("~", user_name, "/a/b");
125 		  one_test ("~", user_name, "x\\x\\x////x\\a");
126 		}
127 
128 	      const char *user_name = repeating_string (base_sizes[base_idx]);
129 	      one_test ("~", user_name, "");
130 	      one_test ("~", user_name, "/");
131 	      one_test ("~", user_name, "/a");
132 	      one_test ("~", user_name, "/*/*");
133 	      one_test ("~", user_name, "\\/");
134 	      one_test ("/~", user_name, "");
135 	      one_test ("*/~", user_name, "/a/b");
136 	    }
137 
138   free (repeat);
139 
140   return 0;
141 }
142 
143 #define TIMEOUT 200
144 #include <support/test-driver.c>
145