1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
|
/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 1991, 1992 Linus Torvalds
* Copyright (C) 1994 - 2000, 2006 Ralf Baechle
* Copyright (C) 1999, 2000 Silicon Graphics, Inc.
* Copyright (C) 2016, Imagination Technologies Ltd.
*/
#include <linux/compiler.h>
#include <linux/errno.h>
#include <linux/signal.h>
#include <linux/sched/signal.h>
#include <linux/uaccess.h>
#include <asm/abi.h>
#include <asm/compat-signal.h>
#include <asm/dsp.h>
#include <asm/sim.h>
#include <asm/unistd.h>
#include <asm/syscalls.h>
#include "signal-common.h"
/*
* Including <asm/unistd.h> would give use the 64-bit syscall numbers ...
*/
#define __NR_O32_restart_syscall 4253
struct sigframe32 {
u32 sf_ass[4]; /* argument save space for o32 */
u32 sf_pad[2]; /* Was: signal trampoline */
struct sigcontext32 sf_sc;
compat_sigset_t sf_mask;
};
struct ucontext32 {
u32 uc_flags;
s32 uc_link;
compat_stack_t uc_stack;
struct sigcontext32 uc_mcontext;
compat_sigset_t uc_sigmask; /* mask last for extensibility */
};
struct rt_sigframe32 {
u32 rs_ass[4]; /* argument save space for o32 */
u32 rs_pad[2]; /* Was: signal trampoline */
compat_siginfo_t rs_info;
struct ucontext32 rs_uc;
};
static int setup_sigcontext32(struct pt_regs *regs,
struct sigcontext32 __user *sc)
{
int err = 0;
int i;
err |= __put_user(regs->cp0_epc, &sc->sc_pc);
err |= __put_user(0, &sc->sc_regs[0]);
for (i = 1; i < 32; i++)
err |= __put_user(regs->regs[i], &sc->sc_regs[i]);
err |= __put_user(regs->hi, &sc->sc_mdhi);
err |= __put_user(regs->lo, &sc->sc_mdlo);
if (cpu_has_dsp) {
err |= __put_user(rddsp(DSP_MASK), &sc->sc_dsp);
err |= __put_user(mfhi1(), &sc->sc_hi1);
err |= __put_user(mflo1(), &sc->sc_lo1);
err |= __put_user(mfhi2(), &sc->sc_hi2);
err |= __put_user(mflo2(), &sc->sc_lo2);
err |= __put_user(mfhi3(), &sc->sc_hi3);
err |= __put_user(mflo3(), &sc->sc_lo3);
}
/*
* Save FPU state to signal context. Signal handler
* will "inherit" current FPU state.
*/
err |= protected_save_fp_context(sc);
return err;
}
static int restore_sigcontext32(struct pt_regs *regs,
struct sigcontext32 __user *sc)
{
int err = 0;
s32 treg;
int i;
/* Always make any pending restarted system calls return -EINTR */
current->restart_block.fn = do_no_restart_syscall;
err |= __get_user(regs->cp0_epc, &sc->sc_pc);
err |= __get_user(regs->hi, &sc->sc_mdhi);
err |= __get_user(regs->lo, &sc->sc_mdlo);
if (cpu_has_dsp) {
err |= __get_user(treg, &sc->sc_hi1); mthi1(treg);
err |= __get_user(treg, &sc->sc_lo1); mtlo1(treg);
err |= __get_user(treg, &sc->sc_hi2); mthi2(treg);
err |= __get_user(treg, &sc->sc_lo2); mtlo2(treg);
err |= __get_user(treg, &sc->sc_hi3); mthi3(treg);
err |= __get_user(treg, &sc->sc_lo3); mtlo3(treg);
err |= __get_user(treg, &sc->sc_dsp); wrdsp(treg, DSP_MASK);
}
for (i = 1; i < 32; i++)
err |= __get_user(regs->regs[i], &sc->sc_regs[i]);
return err ?: protected_restore_fp_context(sc);
}
static int setup_frame_32(void *sig_return, struct ksignal *ksig,
struct pt_regs *regs, sigset_t *set)
{
struct sigframe32 __user *frame;
int err = 0;
frame = get_sigframe(ksig, regs, sizeof(*frame));
if (!access_ok(frame, sizeof (*frame)))
return -EFAULT;
err |= setup_sigcontext32(regs, &frame->sf_sc);
err |= __copy_conv_sigset_to_user(&frame->sf_mask, set);
if (err)
return -EFAULT;
/*
* Arguments to signal handler:
*
* a0 = signal number
* a1 = 0 (should be cause)
* a2 = pointer to struct sigcontext
*
* $25 and c0_epc point to the signal handler, $29 points to the
* struct sigframe.
*/
regs->regs[ 4] = ksig->sig;
regs->regs[ 5] = 0;
regs->regs[ 6] = (unsigned long) &frame->sf_sc;
regs->regs[29] = (unsigned long) frame;
regs->regs[31] = (unsigned long) sig_return;
regs->cp0_epc = regs->regs[25] = (unsigned long) ksig->ka.sa.sa_handler;
DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n",
current->comm, current->pid,
frame, regs->cp0_epc, regs->regs[31]);
return 0;
}
asmlinkage void sys32_rt_sigreturn(void)
{
struct rt_sigframe32 __user *frame;
struct pt_regs *regs;
sigset_t set;
int sig;
regs = current_pt_regs();
frame = (struct rt_sigframe32 __user *)regs->regs[29];
if (!access_ok(frame, sizeof(*frame)))
goto badframe;
if (__copy_conv_sigset_from_user(&set, &frame->rs_uc.uc_sigmask))
goto badframe;
set_current_blocked(&set);
sig = restore_sigcontext32(regs, &frame->rs_uc.uc_mcontext);
if (sig < 0)
goto badframe;
else if (sig)
force_sig(sig);
if (compat_restore_altstack(&frame->rs_uc.uc_stack))
goto badframe;
/*
* Don't let your children do this ...
*/
__asm__ __volatile__(
"move\t$29, %0\n\t"
"j\tsyscall_exit"
: /* no outputs */
: "r" (regs));
/* Unreached */
badframe:
force_sig(SIGSEGV);
}
static int setup_rt_frame_32(void *sig_return, struct ksignal *ksig,
struct pt_regs *regs, sigset_t *set)
{
struct rt_sigframe32 __user *frame;
int err = 0;
frame = get_sigframe(ksig, regs, sizeof(*frame));
if (!access_ok(frame, sizeof (*frame)))
return -EFAULT;
/* Convert (siginfo_t -> compat_siginfo_t) and copy to user. */
err |= copy_siginfo_to_user32(&frame->rs_info, &ksig->info);
/* Create the ucontext. */
err |= __put_user(0, &frame->rs_uc.uc_flags);
err |= __put_user(0, &frame->rs_uc.uc_link);
err |= __compat_save_altstack(&frame->rs_uc.uc_stack, regs->regs[29]);
err |= setup_sigcontext32(regs, &frame->rs_uc.uc_mcontext);
err |= __copy_conv_sigset_to_user(&frame->rs_uc.uc_sigmask, set);
if (err)
return -EFAULT;
/*
* Arguments to signal handler:
*
* a0 = signal number
* a1 = 0 (should be cause)
* a2 = pointer to ucontext
*
* $25 and c0_epc point to the signal handler, $29 points to
* the struct rt_sigframe32.
*/
regs->regs[ 4] = ksig->sig;
regs->regs[ 5] = (unsigned long) &frame->rs_info;
regs->regs[ 6] = (unsigned long) &frame->rs_uc;
regs->regs[29] = (unsigned long) frame;
regs->regs[31] = (unsigned long) sig_return;
regs->cp0_epc = regs->regs[25] = (unsigned long) ksig->ka.sa.sa_handler;
DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n",
current->comm, current->pid,
frame, regs->cp0_epc, regs->regs[31]);
return 0;
}
/*
* o32 compatibility on 64-bit kernels, without DSP ASE
*/
struct mips_abi mips_abi_32 = {
.setup_frame = setup_frame_32,
.setup_rt_frame = setup_rt_frame_32,
.restart = __NR_O32_restart_syscall,
.off_sc_fpregs = offsetof(struct sigcontext32, sc_fpregs),
.off_sc_fpc_csr = offsetof(struct sigcontext32, sc_fpc_csr),
.off_sc_used_math = offsetof(struct sigcontext32, sc_used_math),
.vdso = &vdso_image_o32,
};
asmlinkage void sys32_sigreturn(void)
{
struct sigframe32 __user *frame;
struct pt_regs *regs;
sigset_t blocked;
int sig;
regs = current_pt_regs();
frame = (struct sigframe32 __user *)regs->regs[29];
if (!access_ok(frame, sizeof(*frame)))
goto badframe;
if (__copy_conv_sigset_from_user(&blocked, &frame->sf_mask))
goto badframe;
set_current_blocked(&blocked);
sig = restore_sigcontext32(regs, &frame->sf_sc);
if (sig < 0)
goto badframe;
else if (sig)
force_sig(sig);
/*
* Don't let your children do this ...
*/
__asm__ __volatile__(
"move\t$29, %0\n\t"
"j\tsyscall_exit"
: /* no outputs */
: "r" (regs));
/* Unreached */
badframe:
force_sig(SIGSEGV);
}
|
