Branch data Line data Source code
1 : : /*
2 : : * Copyright (c) 1999-2000 Wichert Akkerman <wichert@cistron.nl>
3 : : * Copyright (c) 2002-2005 Roland McGrath <roland@redhat.com>
4 : : * Copyright (c) 2008 Jan Kratochvil <jan.kratochvil@redhat.com>
5 : : * Copyright (c) 2009-2013 Denys Vlasenko <dvlasenk@redhat.com>
6 : : * Copyright (c) 2006-2015 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 : : #include <sched.h>
35 : : #include <asm/unistd.h>
36 : :
37 : : #ifndef CSIGNAL
38 : : # define CSIGNAL 0x000000ff
39 : : #endif
40 : :
41 : : #include "xlat/clone_flags.h"
42 : : #include "xlat/setns_types.h"
43 : : #include "xlat/unshare_flags.h"
44 : :
45 : : #if defined IA64
46 : : # define ARG_FLAGS 0
47 : : # define ARG_STACK 1
48 : : # define ARG_STACKSIZE (tcp->scno == __NR_clone2 ? 2 : -1)
49 : : # define ARG_PTID (tcp->scno == __NR_clone2 ? 3 : 2)
50 : : # define ARG_CTID (tcp->scno == __NR_clone2 ? 4 : 3)
51 : : # define ARG_TLS (tcp->scno == __NR_clone2 ? 5 : 4)
52 : : #elif defined S390 || defined S390X || defined CRISV10 || defined CRISV32
53 : : # define ARG_STACK 0
54 : : # define ARG_FLAGS 1
55 : : # define ARG_PTID 2
56 : : # define ARG_CTID 3
57 : : # define ARG_TLS 4
58 : : #elif defined X86_64 || defined X32
59 : : /* x86 personality processes have the last two arguments flipped. */
60 : : # define ARG_FLAGS 0
61 : : # define ARG_STACK 1
62 : : # define ARG_PTID 2
63 : : # define ARG_CTID ((current_personality != 1) ? 3 : 4)
64 : : # define ARG_TLS ((current_personality != 1) ? 4 : 3)
65 : : #elif defined ALPHA || defined TILE || defined OR1K || defined RISCV
66 : : # define ARG_FLAGS 0
67 : : # define ARG_STACK 1
68 : : # define ARG_PTID 2
69 : : # define ARG_CTID 3
70 : : # define ARG_TLS 4
71 : : #else
72 : : # define ARG_FLAGS 0
73 : : # define ARG_STACK 1
74 : : # define ARG_PTID 2
75 : : # define ARG_TLS 3
76 : : # define ARG_CTID 4
77 : : #endif
78 : :
79 : : static void
80 : 0 : print_tls_arg(struct tcb *const tcp, const kernel_ulong_t addr)
81 : : {
82 : : #ifdef HAVE_STRUCT_USER_DESC
83 : : # if SUPPORTED_PERSONALITIES > 1
84 [ # # ]: 0 : if (current_personality == 1)
85 : : # endif
86 : : {
87 [ # # ]: 0 : print_user_desc(tcp, tcp->u_arg[ARG_TLS]);
88 : : }
89 : : # if SUPPORTED_PERSONALITIES > 1
90 : : else
91 : : # endif
92 : : #endif /* HAVE_STRUCT_USER_DESC */
93 : : {
94 [ # # ]: 0 : printaddr(tcp->u_arg[ARG_TLS]);
95 : : }
96 : 0 : }
97 : :
98 : 4 : SYS_FUNC(clone)
99 : : {
100 [ + + ]: 4 : if (exiting(tcp)) {
101 : 2 : const char *sep = "|";
102 : 2 : kernel_ulong_t flags = tcp->u_arg[ARG_FLAGS];
103 : 2 : tprints("child_stack=");
104 : 2 : printaddr(tcp->u_arg[ARG_STACK]);
105 : 2 : tprints(", ");
106 : : #ifdef ARG_STACKSIZE
107 : : if (ARG_STACKSIZE != -1)
108 : : tprintf("stack_size=%#" PRI_klx ", ",
109 : : tcp->u_arg[ARG_STACKSIZE]);
110 : : #endif
111 : 2 : tprints("flags=");
112 [ - + ]: 2 : if (!printflags64(clone_flags, flags & ~CSIGNAL, NULL))
113 : 0 : sep = "";
114 [ + - ]: 2 : if ((flags & CSIGNAL) != 0)
115 : 2 : tprintf("%s%s", sep, signame(flags & CSIGNAL));
116 [ + - ]: 2 : if ((flags & (CLONE_PARENT_SETTID|CLONE_CHILD_SETTID
117 : : |CLONE_CHILD_CLEARTID|CLONE_SETTLS)) == 0)
118 : : return 0;
119 [ - + ]: 2 : if (flags & CLONE_PARENT_SETTID) {
120 : 0 : tprints(", parent_tidptr=");
121 : 0 : printaddr(tcp->u_arg[ARG_PTID]);
122 : : }
123 [ - + ]: 2 : if (flags & CLONE_SETTLS) {
124 : 0 : tprints(", tls=");
125 : 0 : print_tls_arg(tcp, tcp->u_arg[ARG_TLS]);
126 : : }
127 [ + - ]: 2 : if (flags & (CLONE_CHILD_SETTID|CLONE_CHILD_CLEARTID)) {
128 : 2 : tprints(", child_tidptr=");
129 [ + + ]: 2 : printaddr(tcp->u_arg[ARG_CTID]);
130 : : }
131 : : }
132 : : /* TODO on syscall entry:
133 : : * We can clear CLONE_PTRACE here since it is an ancient hack
134 : : * to allow us to catch children, and we use another hack for that.
135 : : * But CLONE_PTRACE can conceivably be used by malicious programs
136 : : * to subvert us. By clearing this bit, we can defend against it:
137 : : * in untraced execution, CLONE_PTRACE should have no effect.
138 : : *
139 : : * We can also clear CLONE_UNTRACED, since it allows to start
140 : : * children outside of our control. At the moment
141 : : * I'm trying to figure out whether there is a *legitimate*
142 : : * use of this flag which we should respect.
143 : : */
144 : : return 0;
145 : : }
146 : :
147 : 6 : SYS_FUNC(setns)
148 : : {
149 : 6 : printfd(tcp, tcp->u_arg[0]);
150 : 6 : tprints(", ");
151 : 6 : printxval(setns_types, tcp->u_arg[1], "CLONE_NEW???");
152 : :
153 : 6 : return RVAL_DECODED;
154 : : }
155 : :
156 : 10 : SYS_FUNC(unshare)
157 : : {
158 : 10 : printflags64(unshare_flags, tcp->u_arg[0], "CLONE_???");
159 : 10 : return RVAL_DECODED;
160 : : }
161 : :
162 : 0 : SYS_FUNC(fork)
163 : : {
164 : 0 : return RVAL_DECODED | RVAL_UDECIMAL;
165 : : }
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