Loading...
1#include <linux/compat.h>
2#include <linux/uaccess.h>
3
4int copy_siginfo_to_user32(compat_siginfo_t __user *to, const siginfo_t *from)
5{
6 int err = 0;
7 bool ia32 = test_thread_flag(TIF_IA32);
8
9 if (!access_ok(VERIFY_WRITE, to, sizeof(compat_siginfo_t)))
10 return -EFAULT;
11
12 put_user_try {
13 /* If you change siginfo_t structure, please make sure that
14 this code is fixed accordingly.
15 It should never copy any pad contained in the structure
16 to avoid security leaks, but must copy the generic
17 3 ints plus the relevant union member. */
18 put_user_ex(from->si_signo, &to->si_signo);
19 put_user_ex(from->si_errno, &to->si_errno);
20 put_user_ex((short)from->si_code, &to->si_code);
21
22 if (from->si_code < 0) {
23 put_user_ex(from->si_pid, &to->si_pid);
24 put_user_ex(from->si_uid, &to->si_uid);
25 put_user_ex(ptr_to_compat(from->si_ptr), &to->si_ptr);
26 } else {
27 /*
28 * First 32bits of unions are always present:
29 * si_pid === si_band === si_tid === si_addr(LS half)
30 */
31 put_user_ex(from->_sifields._pad[0],
32 &to->_sifields._pad[0]);
33 switch (from->si_code >> 16) {
34 case __SI_FAULT >> 16:
35 break;
36 case __SI_SYS >> 16:
37 put_user_ex(from->si_syscall, &to->si_syscall);
38 put_user_ex(from->si_arch, &to->si_arch);
39 break;
40 case __SI_CHLD >> 16:
41 if (ia32) {
42 put_user_ex(from->si_utime, &to->si_utime);
43 put_user_ex(from->si_stime, &to->si_stime);
44 } else {
45 put_user_ex(from->si_utime, &to->_sifields._sigchld_x32._utime);
46 put_user_ex(from->si_stime, &to->_sifields._sigchld_x32._stime);
47 }
48 put_user_ex(from->si_status, &to->si_status);
49 /* FALL THROUGH */
50 default:
51 case __SI_KILL >> 16:
52 put_user_ex(from->si_uid, &to->si_uid);
53 break;
54 case __SI_POLL >> 16:
55 put_user_ex(from->si_fd, &to->si_fd);
56 break;
57 case __SI_TIMER >> 16:
58 put_user_ex(from->si_overrun, &to->si_overrun);
59 put_user_ex(ptr_to_compat(from->si_ptr),
60 &to->si_ptr);
61 break;
62 /* This is not generated by the kernel as of now. */
63 case __SI_RT >> 16:
64 case __SI_MESGQ >> 16:
65 put_user_ex(from->si_uid, &to->si_uid);
66 put_user_ex(from->si_int, &to->si_int);
67 break;
68 }
69 }
70 } put_user_catch(err);
71
72 return err;
73}
74
75int copy_siginfo_from_user32(siginfo_t *to, compat_siginfo_t __user *from)
76{
77 int err = 0;
78 u32 ptr32;
79
80 if (!access_ok(VERIFY_READ, from, sizeof(compat_siginfo_t)))
81 return -EFAULT;
82
83 get_user_try {
84 get_user_ex(to->si_signo, &from->si_signo);
85 get_user_ex(to->si_errno, &from->si_errno);
86 get_user_ex(to->si_code, &from->si_code);
87
88 get_user_ex(to->si_pid, &from->si_pid);
89 get_user_ex(to->si_uid, &from->si_uid);
90 get_user_ex(ptr32, &from->si_ptr);
91 to->si_ptr = compat_ptr(ptr32);
92 } get_user_catch(err);
93
94 return err;
95}
1// SPDX-License-Identifier: GPL-2.0
2#include <linux/compat.h>
3#include <linux/uaccess.h>
4#include <linux/ptrace.h>
5
6/*
7 * The compat_siginfo_t structure and handing code is very easy
8 * to break in several ways. It must always be updated when new
9 * updates are made to the main siginfo_t, and
10 * copy_siginfo_to_user32() must be updated when the
11 * (arch-independent) copy_siginfo_to_user() is updated.
12 *
13 * It is also easy to put a new member in the compat_siginfo_t
14 * which has implicit alignment which can move internal structure
15 * alignment around breaking the ABI. This can happen if you,
16 * for instance, put a plain 64-bit value in there.
17 */
18static inline void signal_compat_build_tests(void)
19{
20 int _sifields_offset = offsetof(compat_siginfo_t, _sifields);
21
22 /*
23 * If adding a new si_code, there is probably new data in
24 * the siginfo. Make sure folks bumping the si_code
25 * limits also have to look at this code. Make sure any
26 * new fields are handled in copy_siginfo_to_user32()!
27 */
28 BUILD_BUG_ON(NSIGILL != 11);
29 BUILD_BUG_ON(NSIGFPE != 15);
30 BUILD_BUG_ON(NSIGSEGV != 9);
31 BUILD_BUG_ON(NSIGBUS != 5);
32 BUILD_BUG_ON(NSIGTRAP != 6);
33 BUILD_BUG_ON(NSIGCHLD != 6);
34 BUILD_BUG_ON(NSIGSYS != 2);
35
36 /* This is part of the ABI and can never change in size: */
37 BUILD_BUG_ON(sizeof(siginfo_t) != 128);
38 BUILD_BUG_ON(sizeof(compat_siginfo_t) != 128);
39
40 /* This is a part of the ABI and can never change in alignment */
41 BUILD_BUG_ON(__alignof__(siginfo_t) != 8);
42 BUILD_BUG_ON(__alignof__(compat_siginfo_t) != 4);
43
44 /*
45 * The offsets of all the (unioned) si_fields are fixed
46 * in the ABI, of course. Make sure none of them ever
47 * move and are always at the beginning:
48 */
49 BUILD_BUG_ON(offsetof(compat_siginfo_t, _sifields) != 3 * sizeof(int));
50#define CHECK_CSI_OFFSET(name) BUILD_BUG_ON(_sifields_offset != offsetof(compat_siginfo_t, _sifields.name))
51
52 BUILD_BUG_ON(offsetof(siginfo_t, si_signo) != 0);
53 BUILD_BUG_ON(offsetof(siginfo_t, si_errno) != 4);
54 BUILD_BUG_ON(offsetof(siginfo_t, si_code) != 8);
55
56 BUILD_BUG_ON(offsetof(compat_siginfo_t, si_signo) != 0);
57 BUILD_BUG_ON(offsetof(compat_siginfo_t, si_errno) != 4);
58 BUILD_BUG_ON(offsetof(compat_siginfo_t, si_code) != 8);
59 /*
60 * Ensure that the size of each si_field never changes.
61 * If it does, it is a sign that the
62 * copy_siginfo_to_user32() code below needs to updated
63 * along with the size in the CHECK_SI_SIZE().
64 *
65 * We repeat this check for both the generic and compat
66 * siginfos.
67 *
68 * Note: it is OK for these to grow as long as the whole
69 * structure stays within the padding size (checked
70 * above).
71 */
72#define CHECK_CSI_SIZE(name, size) BUILD_BUG_ON(size != sizeof(((compat_siginfo_t *)0)->_sifields.name))
73#define CHECK_SI_SIZE(name, size) BUILD_BUG_ON(size != sizeof(((siginfo_t *)0)->_sifields.name))
74
75 CHECK_CSI_OFFSET(_kill);
76 CHECK_CSI_SIZE (_kill, 2*sizeof(int));
77 CHECK_SI_SIZE (_kill, 2*sizeof(int));
78
79 BUILD_BUG_ON(offsetof(siginfo_t, si_pid) != 0x10);
80 BUILD_BUG_ON(offsetof(siginfo_t, si_uid) != 0x14);
81 BUILD_BUG_ON(offsetof(compat_siginfo_t, si_pid) != 0xC);
82 BUILD_BUG_ON(offsetof(compat_siginfo_t, si_uid) != 0x10);
83
84 CHECK_CSI_OFFSET(_timer);
85 CHECK_CSI_SIZE (_timer, 3*sizeof(int));
86 CHECK_SI_SIZE (_timer, 6*sizeof(int));
87
88 BUILD_BUG_ON(offsetof(siginfo_t, si_tid) != 0x10);
89 BUILD_BUG_ON(offsetof(siginfo_t, si_overrun) != 0x14);
90 BUILD_BUG_ON(offsetof(siginfo_t, si_value) != 0x18);
91 BUILD_BUG_ON(offsetof(compat_siginfo_t, si_tid) != 0x0C);
92 BUILD_BUG_ON(offsetof(compat_siginfo_t, si_overrun) != 0x10);
93 BUILD_BUG_ON(offsetof(compat_siginfo_t, si_value) != 0x14);
94
95 CHECK_CSI_OFFSET(_rt);
96 CHECK_CSI_SIZE (_rt, 3*sizeof(int));
97 CHECK_SI_SIZE (_rt, 4*sizeof(int));
98
99 BUILD_BUG_ON(offsetof(siginfo_t, si_pid) != 0x10);
100 BUILD_BUG_ON(offsetof(siginfo_t, si_uid) != 0x14);
101 BUILD_BUG_ON(offsetof(siginfo_t, si_value) != 0x18);
102 BUILD_BUG_ON(offsetof(compat_siginfo_t, si_pid) != 0x0C);
103 BUILD_BUG_ON(offsetof(compat_siginfo_t, si_uid) != 0x10);
104 BUILD_BUG_ON(offsetof(compat_siginfo_t, si_value) != 0x14);
105
106 CHECK_CSI_OFFSET(_sigchld);
107 CHECK_CSI_SIZE (_sigchld, 5*sizeof(int));
108 CHECK_SI_SIZE (_sigchld, 8*sizeof(int));
109
110 BUILD_BUG_ON(offsetof(siginfo_t, si_pid) != 0x10);
111 BUILD_BUG_ON(offsetof(siginfo_t, si_uid) != 0x14);
112 BUILD_BUG_ON(offsetof(siginfo_t, si_status) != 0x18);
113 BUILD_BUG_ON(offsetof(siginfo_t, si_utime) != 0x20);
114 BUILD_BUG_ON(offsetof(siginfo_t, si_stime) != 0x28);
115 BUILD_BUG_ON(offsetof(compat_siginfo_t, si_pid) != 0x0C);
116 BUILD_BUG_ON(offsetof(compat_siginfo_t, si_uid) != 0x10);
117 BUILD_BUG_ON(offsetof(compat_siginfo_t, si_status) != 0x14);
118 BUILD_BUG_ON(offsetof(compat_siginfo_t, si_utime) != 0x18);
119 BUILD_BUG_ON(offsetof(compat_siginfo_t, si_stime) != 0x1C);
120
121#ifdef CONFIG_X86_X32_ABI
122 CHECK_CSI_OFFSET(_sigchld_x32);
123 CHECK_CSI_SIZE (_sigchld_x32, 7*sizeof(int));
124 /* no _sigchld_x32 in the generic siginfo_t */
125 BUILD_BUG_ON(offsetof(compat_siginfo_t, _sifields._sigchld_x32._utime) != 0x18);
126 BUILD_BUG_ON(offsetof(compat_siginfo_t, _sifields._sigchld_x32._stime) != 0x20);
127#endif
128
129 CHECK_CSI_OFFSET(_sigfault);
130 CHECK_CSI_SIZE (_sigfault, 4*sizeof(int));
131 CHECK_SI_SIZE (_sigfault, 8*sizeof(int));
132
133 BUILD_BUG_ON(offsetof(siginfo_t, si_addr) != 0x10);
134 BUILD_BUG_ON(offsetof(compat_siginfo_t, si_addr) != 0x0C);
135
136 BUILD_BUG_ON(offsetof(siginfo_t, si_trapno) != 0x18);
137 BUILD_BUG_ON(offsetof(compat_siginfo_t, si_trapno) != 0x10);
138
139 BUILD_BUG_ON(offsetof(siginfo_t, si_addr_lsb) != 0x18);
140 BUILD_BUG_ON(offsetof(compat_siginfo_t, si_addr_lsb) != 0x10);
141
142 BUILD_BUG_ON(offsetof(siginfo_t, si_lower) != 0x20);
143 BUILD_BUG_ON(offsetof(siginfo_t, si_upper) != 0x28);
144 BUILD_BUG_ON(offsetof(compat_siginfo_t, si_lower) != 0x14);
145 BUILD_BUG_ON(offsetof(compat_siginfo_t, si_upper) != 0x18);
146
147 BUILD_BUG_ON(offsetof(siginfo_t, si_pkey) != 0x20);
148 BUILD_BUG_ON(offsetof(compat_siginfo_t, si_pkey) != 0x14);
149
150 BUILD_BUG_ON(offsetof(siginfo_t, si_perf_data) != 0x18);
151 BUILD_BUG_ON(offsetof(siginfo_t, si_perf_type) != 0x20);
152 BUILD_BUG_ON(offsetof(siginfo_t, si_perf_flags) != 0x24);
153 BUILD_BUG_ON(offsetof(compat_siginfo_t, si_perf_data) != 0x10);
154 BUILD_BUG_ON(offsetof(compat_siginfo_t, si_perf_type) != 0x14);
155 BUILD_BUG_ON(offsetof(compat_siginfo_t, si_perf_flags) != 0x18);
156
157 CHECK_CSI_OFFSET(_sigpoll);
158 CHECK_CSI_SIZE (_sigpoll, 2*sizeof(int));
159 CHECK_SI_SIZE (_sigpoll, 4*sizeof(int));
160
161 BUILD_BUG_ON(offsetof(siginfo_t, si_band) != 0x10);
162 BUILD_BUG_ON(offsetof(siginfo_t, si_fd) != 0x18);
163 BUILD_BUG_ON(offsetof(compat_siginfo_t, si_band) != 0x0C);
164 BUILD_BUG_ON(offsetof(compat_siginfo_t, si_fd) != 0x10);
165
166 CHECK_CSI_OFFSET(_sigsys);
167 CHECK_CSI_SIZE (_sigsys, 3*sizeof(int));
168 CHECK_SI_SIZE (_sigsys, 4*sizeof(int));
169
170 BUILD_BUG_ON(offsetof(siginfo_t, si_call_addr) != 0x10);
171 BUILD_BUG_ON(offsetof(siginfo_t, si_syscall) != 0x18);
172 BUILD_BUG_ON(offsetof(siginfo_t, si_arch) != 0x1C);
173 BUILD_BUG_ON(offsetof(compat_siginfo_t, si_call_addr) != 0x0C);
174 BUILD_BUG_ON(offsetof(compat_siginfo_t, si_syscall) != 0x10);
175 BUILD_BUG_ON(offsetof(compat_siginfo_t, si_arch) != 0x14);
176
177 /* any new si_fields should be added here */
178}
179
180void sigaction_compat_abi(struct k_sigaction *act, struct k_sigaction *oact)
181{
182 signal_compat_build_tests();
183
184 if (!act)
185 return;
186
187 if (in_ia32_syscall())
188 act->sa.sa_flags |= SA_IA32_ABI;
189 if (in_x32_syscall())
190 act->sa.sa_flags |= SA_X32_ABI;
191}