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) 1993-1996 Rick Sladkey <jrs@world.std.com>
5  * Copyright (c) 1996-1999 Wichert Akkerman <wichert@cistron.nl>
6  * Copyright (c) 2006 Ulrich Drepper <drepper@redhat.com>
7  * Copyright (c) 2006 Bernhard Kaindl <bk@suse.de>
8  * Copyright (c) 2006-2015 Dmitry V. Levin <ldv@altlinux.org>
9  * All rights reserved.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. The name of the author may not be used to endorse or promote products
20  *    derived from this software without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
23  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
24  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
25  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
26  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
27  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
31  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 #include "defs.h"
35 
36 static int
decode_readlink(struct tcb * tcp,int offset)37 decode_readlink(struct tcb *tcp, int offset)
38 {
39 	if (entering(tcp)) {
40 		printpath(tcp, tcp->u_arg[offset]);
41 		tprints(", ");
42 	} else {
43 		if (syserror(tcp))
44 			printaddr(tcp->u_arg[offset + 1]);
45 		else
46 			/* Used to use printpathn(), but readlink
47 			 * neither includes NUL in the returned count,
48 			 * nor actually writes it into memory.
49 			 * printpathn() would decide on printing
50 			 * "..." continuation based on garbage
51 			 * past return buffer's end.
52 			 */
53 			printstr(tcp, tcp->u_arg[offset + 1], tcp->u_rval);
54 		tprintf(", %lu", tcp->u_arg[offset + 2]);
55 	}
56 	return 0;
57 }
58 
SYS_FUNC(readlink)59 SYS_FUNC(readlink)
60 {
61 	return decode_readlink(tcp, 0);
62 }
63 
SYS_FUNC(readlinkat)64 SYS_FUNC(readlinkat)
65 {
66 	if (entering(tcp))
67 		print_dirfd(tcp, tcp->u_arg[0]);
68 	return decode_readlink(tcp, 1);
69 }
70