1 /*
2 * Copyright (c) 1991, 1992 Paul Kranenburg <pk@cs.few.eur.nl>
3 * Copyright (c) 1993 Branko Lankester <branko@hacktic.nl>
4 * Copyright (c) 1993, 1994, 1995, 1996 Rick Sladkey <jrs@world.std.com>
5 * Copyright (c) 1996-1999 Wichert Akkerman <wichert@cistron.nl>
6 * Copyright (c) 2005-2015 Dmitry V. Levin <ldv@altlinux.org>
7 * Copyright (c) 2014-2017 The strace developers.
8 * All rights reserved.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. The name of the author may not be used to endorse or promote products
19 * derived from this software without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
22 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
23 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
24 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
26 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
30 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31 */
32
33 #include "defs.h"
34
35 #include DEF_MPERS_TYPE(kernel_dirent)
36
37 #include MPERS_DEFS
38
39 #define D_NAME_LEN_MAX 256
40
41 static void
print_old_dirent(struct tcb * const tcp,const kernel_ulong_t addr)42 print_old_dirent(struct tcb *const tcp, const kernel_ulong_t addr)
43 {
44 kernel_dirent d;
45
46 if (umove_or_printaddr(tcp, addr, &d))
47 return;
48
49 tprintf("{d_ino=%llu, d_off=%llu, d_reclen=%u, d_name=",
50 zero_extend_signed_to_ull(d.d_ino),
51 zero_extend_signed_to_ull(d.d_off), d.d_reclen);
52 if (d.d_reclen > D_NAME_LEN_MAX)
53 d.d_reclen = D_NAME_LEN_MAX;
54 printpathn(tcp, addr + offsetof(kernel_dirent, d_name), d.d_reclen);
55 tprints("}");
56 }
57
SYS_FUNC(readdir)58 SYS_FUNC(readdir)
59 {
60 if (entering(tcp)) {
61 printfd(tcp, tcp->u_arg[0]);
62 tprints(", ");
63 } else {
64 if (tcp->u_rval == 0)
65 printaddr(tcp->u_arg[1]);
66 else
67 print_old_dirent(tcp, tcp->u_arg[1]);
68 /* Not much point in printing this out, it is always 1. */
69 if (tcp->u_arg[2] != 1)
70 tprintf(", %" PRI_klu, tcp->u_arg[2]);
71 }
72 return 0;
73 }
74
SYS_FUNC(getdents)75 SYS_FUNC(getdents)
76 {
77 unsigned int i, len, dents = 0;
78 unsigned char *buf;
79
80 if (entering(tcp)) {
81 printfd(tcp, tcp->u_arg[0]);
82 return 0;
83 }
84
85 const unsigned int count = tcp->u_arg[2];
86
87 if (syserror(tcp) || !verbose(tcp)) {
88 tprints(", ");
89 printaddr(tcp->u_arg[1]);
90 tprintf(", %u", count);
91 return 0;
92 }
93
94 /* Beware of insanely large or too small values in tcp->u_rval */
95 if (tcp->u_rval > 1024*1024)
96 len = 1024*1024;
97 else if (tcp->u_rval < (int) sizeof(kernel_dirent))
98 len = 0;
99 else
100 len = tcp->u_rval;
101
102 if (len) {
103 buf = malloc(len);
104 if (!buf || umoven(tcp, tcp->u_arg[1], len, buf) < 0) {
105 tprints(", ");
106 printaddr(tcp->u_arg[1]);
107 tprintf(", %u", count);
108 free(buf);
109 return 0;
110 }
111 } else {
112 buf = NULL;
113 }
114
115 tprints(",");
116 if (!abbrev(tcp))
117 tprints(" [");
118 for (i = 0; len && i <= len - sizeof(kernel_dirent); ) {
119 kernel_dirent *d = (kernel_dirent *) &buf[i];
120
121 if (!abbrev(tcp)) {
122 int oob = d->d_reclen < sizeof(kernel_dirent) ||
123 i + d->d_reclen - 1 >= len;
124 int d_name_len = oob ? len - i : d->d_reclen;
125 d_name_len -= offsetof(kernel_dirent, d_name) + 1;
126 if (d_name_len > D_NAME_LEN_MAX)
127 d_name_len = D_NAME_LEN_MAX;
128
129 tprintf("%s{d_ino=%llu, d_off=%llu, d_reclen=%u"
130 ", d_name=", i ? ", " : "",
131 zero_extend_signed_to_ull(d->d_ino),
132 zero_extend_signed_to_ull(d->d_off),
133 d->d_reclen);
134
135 print_quoted_cstring(d->d_name, d_name_len);
136
137 tprints(", d_type=");
138 if (oob)
139 tprints("?");
140 else
141 printxval(dirent_types, buf[i + d->d_reclen - 1], "DT_???");
142 tprints("}");
143 }
144 dents++;
145 if (d->d_reclen < sizeof(kernel_dirent)) {
146 tprints_comment("d_reclen < sizeof(struct dirent)");
147 break;
148 }
149 i += d->d_reclen;
150 }
151 if (!abbrev(tcp))
152 tprints("]");
153 else
154 tprintf_comment("%u entries", dents);
155 tprintf(", %u", count);
156 free(buf);
157 return 0;
158 }
159