Harvey Hunt | d1e63c9 | 2016-06-17 16:03:45 +0100 | [diff] [blame] | 1 | /* |
| 2 | * This file is subject to the terms and conditions of the GNU General Public |
| 3 | * License. See the file "COPYING" in the main directory of this archive |
| 4 | * for more details. |
| 5 | * |
| 6 | * Copyright (C) 1991, 1992 Linus Torvalds |
| 7 | * Copyright (C) 1994 - 2000, 2006 Ralf Baechle |
| 8 | * Copyright (C) 1999, 2000 Silicon Graphics, Inc. |
| 9 | * Copyright (C) 2016, Imagination Technologies Ltd. |
| 10 | */ |
| 11 | #include <linux/compiler.h> |
| 12 | #include <linux/errno.h> |
| 13 | #include <linux/signal.h> |
| 14 | #include <linux/uaccess.h> |
| 15 | |
| 16 | #include <asm/abi.h> |
| 17 | #include <asm/compat-signal.h> |
| 18 | #include <asm/dsp.h> |
| 19 | #include <asm/sim.h> |
| 20 | #include <asm/unistd.h> |
| 21 | |
| 22 | #include "signal-common.h" |
| 23 | |
| 24 | /* |
| 25 | * Including <asm/unistd.h> would give use the 64-bit syscall numbers ... |
| 26 | */ |
| 27 | #define __NR_O32_restart_syscall 4253 |
| 28 | |
| 29 | struct sigframe32 { |
| 30 | u32 sf_ass[4]; /* argument save space for o32 */ |
| 31 | u32 sf_pad[2]; /* Was: signal trampoline */ |
| 32 | struct sigcontext32 sf_sc; |
| 33 | compat_sigset_t sf_mask; |
| 34 | }; |
| 35 | |
| 36 | struct ucontext32 { |
| 37 | u32 uc_flags; |
| 38 | s32 uc_link; |
| 39 | compat_stack_t uc_stack; |
| 40 | struct sigcontext32 uc_mcontext; |
| 41 | compat_sigset_t uc_sigmask; /* mask last for extensibility */ |
| 42 | }; |
| 43 | |
| 44 | struct rt_sigframe32 { |
| 45 | u32 rs_ass[4]; /* argument save space for o32 */ |
| 46 | u32 rs_pad[2]; /* Was: signal trampoline */ |
| 47 | compat_siginfo_t rs_info; |
| 48 | struct ucontext32 rs_uc; |
| 49 | }; |
| 50 | |
| 51 | static int setup_sigcontext32(struct pt_regs *regs, |
| 52 | struct sigcontext32 __user *sc) |
| 53 | { |
| 54 | int err = 0; |
| 55 | int i; |
| 56 | |
| 57 | err |= __put_user(regs->cp0_epc, &sc->sc_pc); |
| 58 | |
| 59 | err |= __put_user(0, &sc->sc_regs[0]); |
| 60 | for (i = 1; i < 32; i++) |
| 61 | err |= __put_user(regs->regs[i], &sc->sc_regs[i]); |
| 62 | |
| 63 | err |= __put_user(regs->hi, &sc->sc_mdhi); |
| 64 | err |= __put_user(regs->lo, &sc->sc_mdlo); |
| 65 | if (cpu_has_dsp) { |
| 66 | err |= __put_user(rddsp(DSP_MASK), &sc->sc_dsp); |
| 67 | err |= __put_user(mfhi1(), &sc->sc_hi1); |
| 68 | err |= __put_user(mflo1(), &sc->sc_lo1); |
| 69 | err |= __put_user(mfhi2(), &sc->sc_hi2); |
| 70 | err |= __put_user(mflo2(), &sc->sc_lo2); |
| 71 | err |= __put_user(mfhi3(), &sc->sc_hi3); |
| 72 | err |= __put_user(mflo3(), &sc->sc_lo3); |
| 73 | } |
| 74 | |
| 75 | /* |
| 76 | * Save FPU state to signal context. Signal handler |
| 77 | * will "inherit" current FPU state. |
| 78 | */ |
| 79 | err |= protected_save_fp_context(sc); |
| 80 | |
| 81 | return err; |
| 82 | } |
| 83 | |
| 84 | static int restore_sigcontext32(struct pt_regs *regs, |
| 85 | struct sigcontext32 __user *sc) |
| 86 | { |
| 87 | int err = 0; |
| 88 | s32 treg; |
| 89 | int i; |
| 90 | |
| 91 | /* Always make any pending restarted system calls return -EINTR */ |
| 92 | current->restart_block.fn = do_no_restart_syscall; |
| 93 | |
| 94 | err |= __get_user(regs->cp0_epc, &sc->sc_pc); |
| 95 | err |= __get_user(regs->hi, &sc->sc_mdhi); |
| 96 | err |= __get_user(regs->lo, &sc->sc_mdlo); |
| 97 | if (cpu_has_dsp) { |
| 98 | err |= __get_user(treg, &sc->sc_hi1); mthi1(treg); |
| 99 | err |= __get_user(treg, &sc->sc_lo1); mtlo1(treg); |
| 100 | err |= __get_user(treg, &sc->sc_hi2); mthi2(treg); |
| 101 | err |= __get_user(treg, &sc->sc_lo2); mtlo2(treg); |
| 102 | err |= __get_user(treg, &sc->sc_hi3); mthi3(treg); |
| 103 | err |= __get_user(treg, &sc->sc_lo3); mtlo3(treg); |
| 104 | err |= __get_user(treg, &sc->sc_dsp); wrdsp(treg, DSP_MASK); |
| 105 | } |
| 106 | |
| 107 | for (i = 1; i < 32; i++) |
| 108 | err |= __get_user(regs->regs[i], &sc->sc_regs[i]); |
| 109 | |
| 110 | return err ?: protected_restore_fp_context(sc); |
| 111 | } |
| 112 | |
| 113 | static int setup_frame_32(void *sig_return, struct ksignal *ksig, |
| 114 | struct pt_regs *regs, sigset_t *set) |
| 115 | { |
| 116 | struct sigframe32 __user *frame; |
| 117 | int err = 0; |
| 118 | |
| 119 | frame = get_sigframe(ksig, regs, sizeof(*frame)); |
| 120 | if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame))) |
| 121 | return -EFAULT; |
| 122 | |
| 123 | err |= setup_sigcontext32(regs, &frame->sf_sc); |
| 124 | err |= __copy_conv_sigset_to_user(&frame->sf_mask, set); |
| 125 | |
| 126 | if (err) |
| 127 | return -EFAULT; |
| 128 | |
| 129 | /* |
| 130 | * Arguments to signal handler: |
| 131 | * |
| 132 | * a0 = signal number |
| 133 | * a1 = 0 (should be cause) |
| 134 | * a2 = pointer to struct sigcontext |
| 135 | * |
| 136 | * $25 and c0_epc point to the signal handler, $29 points to the |
| 137 | * struct sigframe. |
| 138 | */ |
| 139 | regs->regs[ 4] = ksig->sig; |
| 140 | regs->regs[ 5] = 0; |
| 141 | regs->regs[ 6] = (unsigned long) &frame->sf_sc; |
| 142 | regs->regs[29] = (unsigned long) frame; |
| 143 | regs->regs[31] = (unsigned long) sig_return; |
| 144 | regs->cp0_epc = regs->regs[25] = (unsigned long) ksig->ka.sa.sa_handler; |
| 145 | |
| 146 | DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n", |
| 147 | current->comm, current->pid, |
| 148 | frame, regs->cp0_epc, regs->regs[31]); |
| 149 | |
| 150 | return 0; |
| 151 | } |
| 152 | |
| 153 | asmlinkage void sys32_rt_sigreturn(nabi_no_regargs struct pt_regs regs) |
| 154 | { |
| 155 | struct rt_sigframe32 __user *frame; |
| 156 | sigset_t set; |
| 157 | int sig; |
| 158 | |
| 159 | frame = (struct rt_sigframe32 __user *) regs.regs[29]; |
| 160 | if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) |
| 161 | goto badframe; |
| 162 | if (__copy_conv_sigset_from_user(&set, &frame->rs_uc.uc_sigmask)) |
| 163 | goto badframe; |
| 164 | |
| 165 | set_current_blocked(&set); |
| 166 | |
| 167 | sig = restore_sigcontext32(®s, &frame->rs_uc.uc_mcontext); |
| 168 | if (sig < 0) |
| 169 | goto badframe; |
| 170 | else if (sig) |
| 171 | force_sig(sig, current); |
| 172 | |
| 173 | if (compat_restore_altstack(&frame->rs_uc.uc_stack)) |
| 174 | goto badframe; |
| 175 | |
| 176 | /* |
| 177 | * Don't let your children do this ... |
| 178 | */ |
| 179 | __asm__ __volatile__( |
| 180 | "move\t$29, %0\n\t" |
| 181 | "j\tsyscall_exit" |
| 182 | :/* no outputs */ |
| 183 | :"r" (®s)); |
| 184 | /* Unreached */ |
| 185 | |
| 186 | badframe: |
| 187 | force_sig(SIGSEGV, current); |
| 188 | } |
| 189 | |
| 190 | static int setup_rt_frame_32(void *sig_return, struct ksignal *ksig, |
| 191 | struct pt_regs *regs, sigset_t *set) |
| 192 | { |
| 193 | struct rt_sigframe32 __user *frame; |
| 194 | int err = 0; |
| 195 | |
| 196 | frame = get_sigframe(ksig, regs, sizeof(*frame)); |
| 197 | if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame))) |
| 198 | return -EFAULT; |
| 199 | |
| 200 | /* Convert (siginfo_t -> compat_siginfo_t) and copy to user. */ |
| 201 | err |= copy_siginfo_to_user32(&frame->rs_info, &ksig->info); |
| 202 | |
| 203 | /* Create the ucontext. */ |
| 204 | err |= __put_user(0, &frame->rs_uc.uc_flags); |
| 205 | err |= __put_user(0, &frame->rs_uc.uc_link); |
| 206 | err |= __compat_save_altstack(&frame->rs_uc.uc_stack, regs->regs[29]); |
| 207 | err |= setup_sigcontext32(regs, &frame->rs_uc.uc_mcontext); |
| 208 | err |= __copy_conv_sigset_to_user(&frame->rs_uc.uc_sigmask, set); |
| 209 | |
| 210 | if (err) |
| 211 | return -EFAULT; |
| 212 | |
| 213 | /* |
| 214 | * Arguments to signal handler: |
| 215 | * |
| 216 | * a0 = signal number |
| 217 | * a1 = 0 (should be cause) |
| 218 | * a2 = pointer to ucontext |
| 219 | * |
| 220 | * $25 and c0_epc point to the signal handler, $29 points to |
| 221 | * the struct rt_sigframe32. |
| 222 | */ |
| 223 | regs->regs[ 4] = ksig->sig; |
| 224 | regs->regs[ 5] = (unsigned long) &frame->rs_info; |
| 225 | regs->regs[ 6] = (unsigned long) &frame->rs_uc; |
| 226 | regs->regs[29] = (unsigned long) frame; |
| 227 | regs->regs[31] = (unsigned long) sig_return; |
| 228 | regs->cp0_epc = regs->regs[25] = (unsigned long) ksig->ka.sa.sa_handler; |
| 229 | |
| 230 | DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n", |
| 231 | current->comm, current->pid, |
| 232 | frame, regs->cp0_epc, regs->regs[31]); |
| 233 | |
| 234 | return 0; |
| 235 | } |
| 236 | |
| 237 | /* |
| 238 | * o32 compatibility on 64-bit kernels, without DSP ASE |
| 239 | */ |
| 240 | struct mips_abi mips_abi_32 = { |
| 241 | .setup_frame = setup_frame_32, |
| 242 | .setup_rt_frame = setup_rt_frame_32, |
| 243 | .restart = __NR_O32_restart_syscall, |
| 244 | |
| 245 | .off_sc_fpregs = offsetof(struct sigcontext32, sc_fpregs), |
| 246 | .off_sc_fpc_csr = offsetof(struct sigcontext32, sc_fpc_csr), |
| 247 | .off_sc_used_math = offsetof(struct sigcontext32, sc_used_math), |
| 248 | |
| 249 | .vdso = &vdso_image_o32, |
| 250 | }; |
| 251 | |
| 252 | |
| 253 | asmlinkage void sys32_sigreturn(nabi_no_regargs struct pt_regs regs) |
| 254 | { |
| 255 | struct sigframe32 __user *frame; |
| 256 | sigset_t blocked; |
| 257 | int sig; |
| 258 | |
| 259 | frame = (struct sigframe32 __user *) regs.regs[29]; |
| 260 | if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) |
| 261 | goto badframe; |
| 262 | if (__copy_conv_sigset_from_user(&blocked, &frame->sf_mask)) |
| 263 | goto badframe; |
| 264 | |
| 265 | set_current_blocked(&blocked); |
| 266 | |
| 267 | sig = restore_sigcontext32(®s, &frame->sf_sc); |
| 268 | if (sig < 0) |
| 269 | goto badframe; |
| 270 | else if (sig) |
| 271 | force_sig(sig, current); |
| 272 | |
| 273 | /* |
| 274 | * Don't let your children do this ... |
| 275 | */ |
| 276 | __asm__ __volatile__( |
| 277 | "move\t$29, %0\n\t" |
| 278 | "j\tsyscall_exit" |
| 279 | :/* no outputs */ |
| 280 | :"r" (®s)); |
| 281 | /* Unreached */ |
| 282 | |
| 283 | badframe: |
| 284 | force_sig(SIGSEGV, current); |
| 285 | } |