1 /*
2  * Copyright (c) 2015 Dmitry V. Levin <ldv@altlinux.org>
3  * Copyright (c) 2015-2017 The strace developers.
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. The name of the author may not be used to endorse or promote products
15  *    derived from this software without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #include "defs.h"
30 #include "print_fields.h"
31 #include <fcntl.h>
32 
33 #include "xlat/uffd_flags.h"
34 
SYS_FUNC(userfaultfd)35 SYS_FUNC(userfaultfd)
36 {
37 	printflags(uffd_flags, tcp->u_arg[0], "UFFD_???");
38 
39 	return RVAL_DECODED | RVAL_FD;
40 }
41 
42 #ifdef HAVE_LINUX_USERFAULTFD_H
43 # include <linux/ioctl.h>
44 # include <linux/userfaultfd.h>
45 
46 # include "xlat/uffd_api_features.h"
47 # include "xlat/uffd_api_flags.h"
48 # include "xlat/uffd_copy_flags.h"
49 # include "xlat/uffd_register_ioctl_flags.h"
50 # include "xlat/uffd_register_mode_flags.h"
51 # include "xlat/uffd_zeropage_flags.h"
52 
53 static void
tprintf_uffdio_range(const struct uffdio_range * range)54 tprintf_uffdio_range(const struct uffdio_range *range)
55 {
56 	PRINT_FIELD_X("{", *range, start);
57 	PRINT_FIELD_X(", ", *range, len);
58 	tprints("}");
59 }
60 
61 #define PRINT_FIELD_UFFDIO_RANGE(prefix_, where_, field_)		\
62 	do {								\
63 		STRACE_PRINTF("%s%s=", (prefix_), #field_);		\
64 		tprintf_uffdio_range(&(where_).field_);			\
65 	} while (0)
66 
67 int
uffdio_ioctl(struct tcb * const tcp,const unsigned int code,const kernel_ulong_t arg)68 uffdio_ioctl(struct tcb *const tcp, const unsigned int code,
69 	     const kernel_ulong_t arg)
70 {
71 	switch (code) {
72 	case UFFDIO_API: {
73 		uint64_t *entering_features;
74 		struct uffdio_api ua;
75 
76 		if (entering(tcp)) {
77 			tprints(", ");
78 			if (umove_or_printaddr(tcp, arg, &ua))
79 				break;
80 			PRINT_FIELD_X("{", ua, api);
81 			PRINT_FIELD_FLAGS(", ", ua, features, uffd_api_features,
82 					  "UFFD_FEATURE_???");
83 			entering_features = malloc(sizeof(*entering_features));
84 			if (entering_features) {
85 				*entering_features = ua.features;
86 				set_tcb_priv_data(tcp, entering_features, free);
87 			}
88 
89 			return 0;
90 		}
91 
92 		if (!syserror(tcp) && !umove(tcp, arg, &ua)) {
93 			entering_features = get_tcb_priv_data(tcp);
94 
95 			if (!entering_features
96 			    || *entering_features != ua.features) {
97 				PRINT_FIELD_FLAGS(" => ", ua, features,
98 						  uffd_api_features,
99 						  "UFFD_FEATURE_???");
100 			}
101 
102 			PRINT_FIELD_FLAGS(", ", ua, ioctls, uffd_api_flags,
103 					  "_UFFDIO_???");
104 		}
105 
106 		tprints("}");
107 
108 		break;
109 	}
110 
111 	case UFFDIO_COPY: {
112 		struct uffdio_copy uc;
113 
114 		if (entering(tcp)) {
115 			tprints(", ");
116 			if (umove_or_printaddr(tcp, arg, &uc))
117 				return RVAL_IOCTL_DECODED;
118 			PRINT_FIELD_X("{", uc, dst);
119 			PRINT_FIELD_X(", ", uc, src);
120 			PRINT_FIELD_X(", ", uc, len);
121 			PRINT_FIELD_FLAGS(", ", uc, mode, uffd_copy_flags,
122 					  "UFFDIO_COPY_???");
123 
124 			return 0;
125 		}
126 
127 		if (!syserror(tcp) && !umove(tcp, arg, &uc))
128 			PRINT_FIELD_X(", ", uc, copy);
129 
130 		tprints("}");
131 
132 		break;
133 	}
134 
135 	case UFFDIO_REGISTER: {
136 		struct uffdio_register ur;
137 
138 		if (entering(tcp)) {
139 			tprints(", ");
140 			if (umove_or_printaddr(tcp, arg, &ur))
141 				return RVAL_IOCTL_DECODED;
142 			PRINT_FIELD_UFFDIO_RANGE("{", ur, range);
143 			PRINT_FIELD_FLAGS(", ", ur, mode,
144 					  uffd_register_mode_flags,
145 					  "UFFDIO_REGISTER_MODE_???");
146 
147 			return 0;
148 		}
149 
150 		if (!syserror(tcp) && !umove(tcp, arg, &ur)) {
151 			PRINT_FIELD_FLAGS(", ", ur, ioctls,
152 					  uffd_register_ioctl_flags,
153 					  "UFFDIO_???");
154 		}
155 
156 		tprints("}");
157 
158 		break;
159 	}
160 
161 	case UFFDIO_UNREGISTER:
162 	case UFFDIO_WAKE: {
163 		struct uffdio_range ura;
164 
165 		tprints(", ");
166 
167 		if (!umove_or_printaddr(tcp, arg, &ura))
168 			tprintf_uffdio_range(&ura);
169 
170 		break;
171 	}
172 
173 	case UFFDIO_ZEROPAGE: {
174 		struct uffdio_zeropage uz;
175 
176 		if (entering(tcp)) {
177 			tprints(", ");
178 			if (umove_or_printaddr(tcp, arg, &uz))
179 				return RVAL_IOCTL_DECODED;
180 			PRINT_FIELD_UFFDIO_RANGE("{", uz, range);
181 			PRINT_FIELD_FLAGS(", ", uz, mode, uffd_zeropage_flags,
182 					  "UFFDIO_ZEROPAGE_???");
183 
184 			return 0;
185 		}
186 
187 		if (!syserror(tcp) && !umove(tcp, arg, &uz))
188 			PRINT_FIELD_X(", ", uz, zeropage);
189 
190 		tprints("}");
191 
192 		break;
193 	}
194 
195 	default:
196 		return RVAL_DECODED;
197 	}
198 
199 	return RVAL_IOCTL_DECODED;
200 }
201 #endif /* HAVE_LINUX_USERFAULTFD_H */
202