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) 2007 Roland McGrath <roland@redhat.com>
7  * Copyright (c) 2011-2012 Denys Vlasenko <vda.linux@googlemail.com>
8  * Copyright (c) 2010-2015 Dmitry V. Levin <ldv@altlinux.org>
9  * Copyright (c) 2014-2018 The strace developers.
10  * All rights reserved.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  * 3. The name of the author may not be used to endorse or promote products
21  *    derived from this software without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
24  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
25  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
26  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
27  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
28  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
29  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
30  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
31  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
32  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33  */
34 
35 #include "defs.h"
36 
37 static void
printargv(struct tcb * const tcp,kernel_ulong_t addr)38 printargv(struct tcb *const tcp, kernel_ulong_t addr)
39 {
40 	if (!addr || !verbose(tcp)) {
41 		printaddr(addr);
42 		return;
43 	}
44 
45 	const char *const start_sep = "[";
46 	const char *sep = start_sep;
47 	const unsigned int wordsize = current_wordsize;
48 	unsigned int n;
49 
50 	for (n = 0; addr; sep = ", ", addr += wordsize, ++n) {
51 		union {
52 			unsigned int p32;
53 			kernel_ulong_t p64;
54 			char data[sizeof(kernel_ulong_t)];
55 		} cp;
56 
57 		if (umoven(tcp, addr, wordsize, cp.data)) {
58 			if (sep == start_sep)
59 				printaddr(addr);
60 			else {
61 				tprints(", ...");
62 				printaddr_comment(addr);
63 				tprints("]");
64 			}
65 			return;
66 		}
67 		if (!(wordsize < sizeof(cp.p64) ? cp.p32 : cp.p64)) {
68 			if (sep == start_sep)
69 				tprints(start_sep);
70 			break;
71 		}
72 		if (abbrev(tcp) && n >= max_strlen) {
73 			tprintf("%s...", sep);
74 			break;
75 		}
76 		tprints(sep);
77 		printstr(tcp, wordsize < sizeof(cp.p64) ? cp.p32 : cp.p64);
78 	}
79 	tprints("]");
80 }
81 
82 static void
printargc(struct tcb * const tcp,kernel_ulong_t addr)83 printargc(struct tcb *const tcp, kernel_ulong_t addr)
84 {
85 	printaddr(addr);
86 
87 	if (!addr || !verbose(tcp))
88 		return;
89 
90 	bool unterminated = false;
91 	unsigned int count = 0;
92 	char *cp = NULL;
93 
94 	for (; addr; addr += current_wordsize, ++count) {
95 		if (umoven(tcp, addr, current_wordsize, &cp)) {
96 			if (!count)
97 				return;
98 
99 			unterminated = true;
100 			break;
101 		}
102 		if (!cp)
103 			break;
104 	}
105 	tprintf_comment("%u var%s%s",
106 		count, count == 1 ? "" : "s",
107 		unterminated ? ", unterminated" : "");
108 }
109 
110 static void
decode_execve(struct tcb * tcp,const unsigned int index)111 decode_execve(struct tcb *tcp, const unsigned int index)
112 {
113 	printpath(tcp, tcp->u_arg[index + 0]);
114 	tprints(", ");
115 
116 	printargv(tcp, tcp->u_arg[index + 1]);
117 	tprints(", ");
118 
119 	(abbrev(tcp) ? printargc : printargv) (tcp, tcp->u_arg[index + 2]);
120 }
121 
SYS_FUNC(execve)122 SYS_FUNC(execve)
123 {
124 	decode_execve(tcp, 0);
125 
126 	return RVAL_DECODED;
127 }
128 
SYS_FUNC(execveat)129 SYS_FUNC(execveat)
130 {
131 	print_dirfd(tcp, tcp->u_arg[0]);
132 	decode_execve(tcp, 1);
133 	tprints(", ");
134 	printflags(at_flags, tcp->u_arg[4], "AT_???");
135 
136 	return RVAL_DECODED;
137 }
138 
139 #if defined(SPARC) || defined(SPARC64)
SYS_FUNC(execv)140 SYS_FUNC(execv)
141 {
142 	printpath(tcp, tcp->u_arg[0]);
143 	tprints(", ");
144 	printargv(tcp, tcp->u_arg[1]);
145 
146 	return RVAL_DECODED;
147 }
148 #endif /* SPARC || SPARC64 */
149