Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Architecture-specific signal handling support. |
| 3 | * |
| 4 | * Copyright (C) 1999-2004 Hewlett-Packard Co |
| 5 | * David Mosberger-Tang <davidm@hpl.hp.com> |
| 6 | * |
| 7 | * Derived from i386 and Alpha versions. |
| 8 | */ |
| 9 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 10 | #include <linux/errno.h> |
| 11 | #include <linux/kernel.h> |
| 12 | #include <linux/mm.h> |
| 13 | #include <linux/ptrace.h> |
| 14 | #include <linux/sched.h> |
| 15 | #include <linux/signal.h> |
| 16 | #include <linux/smp.h> |
| 17 | #include <linux/smp_lock.h> |
| 18 | #include <linux/stddef.h> |
| 19 | #include <linux/tty.h> |
| 20 | #include <linux/binfmts.h> |
| 21 | #include <linux/unistd.h> |
| 22 | #include <linux/wait.h> |
| 23 | |
| 24 | #include <asm/ia32.h> |
| 25 | #include <asm/intrinsics.h> |
| 26 | #include <asm/uaccess.h> |
| 27 | #include <asm/rse.h> |
| 28 | #include <asm/sigcontext.h> |
| 29 | |
| 30 | #include "sigframe.h" |
| 31 | |
| 32 | #define DEBUG_SIG 0 |
| 33 | #define STACK_ALIGN 16 /* minimal alignment for stack pointer */ |
| 34 | #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP))) |
| 35 | |
| 36 | #if _NSIG_WORDS > 1 |
| 37 | # define PUT_SIGSET(k,u) __copy_to_user((u)->sig, (k)->sig, sizeof(sigset_t)) |
| 38 | # define GET_SIGSET(k,u) __copy_from_user((k)->sig, (u)->sig, sizeof(sigset_t)) |
| 39 | #else |
| 40 | # define PUT_SIGSET(k,u) __put_user((k)->sig[0], &(u)->sig[0]) |
| 41 | # define GET_SIGSET(k,u) __get_user((k)->sig[0], &(u)->sig[0]) |
| 42 | #endif |
| 43 | |
| 44 | long |
| 45 | ia64_rt_sigsuspend (sigset_t __user *uset, size_t sigsetsize, struct sigscratch *scr) |
| 46 | { |
| 47 | sigset_t oldset, set; |
| 48 | |
| 49 | /* XXX: Don't preclude handling different sized sigset_t's. */ |
| 50 | if (sigsetsize != sizeof(sigset_t)) |
| 51 | return -EINVAL; |
| 52 | |
| 53 | if (!access_ok(VERIFY_READ, uset, sigsetsize)) |
| 54 | return -EFAULT; |
| 55 | |
| 56 | if (GET_SIGSET(&set, uset)) |
| 57 | return -EFAULT; |
| 58 | |
| 59 | sigdelsetmask(&set, ~_BLOCKABLE); |
| 60 | |
| 61 | spin_lock_irq(¤t->sighand->siglock); |
| 62 | { |
| 63 | oldset = current->blocked; |
| 64 | current->blocked = set; |
| 65 | recalc_sigpending(); |
| 66 | } |
| 67 | spin_unlock_irq(¤t->sighand->siglock); |
| 68 | |
| 69 | /* |
| 70 | * The return below usually returns to the signal handler. We need to |
| 71 | * pre-set the correct error code here to ensure that the right values |
| 72 | * get saved in sigcontext by ia64_do_signal. |
| 73 | */ |
| 74 | scr->pt.r8 = EINTR; |
| 75 | scr->pt.r10 = -1; |
| 76 | |
| 77 | while (1) { |
| 78 | current->state = TASK_INTERRUPTIBLE; |
| 79 | schedule(); |
| 80 | if (ia64_do_signal(&oldset, scr, 1)) |
| 81 | return -EINTR; |
| 82 | } |
| 83 | } |
| 84 | |
| 85 | asmlinkage long |
| 86 | sys_sigaltstack (const stack_t __user *uss, stack_t __user *uoss, long arg2, |
| 87 | long arg3, long arg4, long arg5, long arg6, long arg7, |
| 88 | struct pt_regs regs) |
| 89 | { |
| 90 | return do_sigaltstack(uss, uoss, regs.r12); |
| 91 | } |
| 92 | |
| 93 | static long |
| 94 | restore_sigcontext (struct sigcontext __user *sc, struct sigscratch *scr) |
| 95 | { |
Matthew Chapman | 4ea7872 | 2005-06-21 16:19:20 -0700 | [diff] [blame] | 96 | unsigned long ip, flags, nat, um, cfm, rsc; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 97 | long err; |
| 98 | |
| 99 | /* Always make any pending restarted system calls return -EINTR */ |
| 100 | current_thread_info()->restart_block.fn = do_no_restart_syscall; |
| 101 | |
| 102 | /* restore scratch that always needs gets updated during signal delivery: */ |
| 103 | err = __get_user(flags, &sc->sc_flags); |
| 104 | err |= __get_user(nat, &sc->sc_nat); |
| 105 | err |= __get_user(ip, &sc->sc_ip); /* instruction pointer */ |
| 106 | err |= __get_user(cfm, &sc->sc_cfm); |
| 107 | err |= __get_user(um, &sc->sc_um); /* user mask */ |
Matthew Chapman | 4ea7872 | 2005-06-21 16:19:20 -0700 | [diff] [blame] | 108 | err |= __get_user(rsc, &sc->sc_ar_rsc); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 109 | err |= __get_user(scr->pt.ar_unat, &sc->sc_ar_unat); |
| 110 | err |= __get_user(scr->pt.ar_fpsr, &sc->sc_ar_fpsr); |
| 111 | err |= __get_user(scr->pt.ar_pfs, &sc->sc_ar_pfs); |
| 112 | err |= __get_user(scr->pt.pr, &sc->sc_pr); /* predicates */ |
| 113 | err |= __get_user(scr->pt.b0, &sc->sc_br[0]); /* b0 (rp) */ |
| 114 | err |= __get_user(scr->pt.b6, &sc->sc_br[6]); /* b6 */ |
| 115 | err |= __copy_from_user(&scr->pt.r1, &sc->sc_gr[1], 8); /* r1 */ |
| 116 | err |= __copy_from_user(&scr->pt.r8, &sc->sc_gr[8], 4*8); /* r8-r11 */ |
| 117 | err |= __copy_from_user(&scr->pt.r12, &sc->sc_gr[12], 2*8); /* r12-r13 */ |
| 118 | err |= __copy_from_user(&scr->pt.r15, &sc->sc_gr[15], 8); /* r15 */ |
| 119 | |
| 120 | scr->pt.cr_ifs = cfm | (1UL << 63); |
Matthew Chapman | 4ea7872 | 2005-06-21 16:19:20 -0700 | [diff] [blame] | 121 | scr->pt.ar_rsc = rsc | (3 << 2); /* force PL3 */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 122 | |
| 123 | /* establish new instruction pointer: */ |
| 124 | scr->pt.cr_iip = ip & ~0x3UL; |
| 125 | ia64_psr(&scr->pt)->ri = ip & 0x3; |
| 126 | scr->pt.cr_ipsr = (scr->pt.cr_ipsr & ~IA64_PSR_UM) | (um & IA64_PSR_UM); |
| 127 | |
| 128 | scr->scratch_unat = ia64_put_scratch_nat_bits(&scr->pt, nat); |
| 129 | |
| 130 | if (!(flags & IA64_SC_FLAG_IN_SYSCALL)) { |
| 131 | /* Restore most scratch-state only when not in syscall. */ |
| 132 | err |= __get_user(scr->pt.ar_ccv, &sc->sc_ar_ccv); /* ar.ccv */ |
| 133 | err |= __get_user(scr->pt.b7, &sc->sc_br[7]); /* b7 */ |
| 134 | err |= __get_user(scr->pt.r14, &sc->sc_gr[14]); /* r14 */ |
| 135 | err |= __copy_from_user(&scr->pt.ar_csd, &sc->sc_ar25, 2*8); /* ar.csd & ar.ssd */ |
| 136 | err |= __copy_from_user(&scr->pt.r2, &sc->sc_gr[2], 2*8); /* r2-r3 */ |
| 137 | err |= __copy_from_user(&scr->pt.r16, &sc->sc_gr[16], 16*8); /* r16-r31 */ |
| 138 | } |
| 139 | |
| 140 | if ((flags & IA64_SC_FLAG_FPH_VALID) != 0) { |
| 141 | struct ia64_psr *psr = ia64_psr(&scr->pt); |
| 142 | |
| 143 | __copy_from_user(current->thread.fph, &sc->sc_fr[32], 96*16); |
| 144 | psr->mfh = 0; /* drop signal handler's fph contents... */ |
Keith Owens | 2ba3e3e | 2005-06-30 22:53:00 -0700 | [diff] [blame] | 145 | preempt_disable(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 146 | if (psr->dfh) |
| 147 | ia64_drop_fpu(current); |
| 148 | else { |
| 149 | /* We already own the local fph, otherwise psr->dfh wouldn't be 0. */ |
| 150 | __ia64_load_fpu(current->thread.fph); |
| 151 | ia64_set_local_fpu_owner(current); |
| 152 | } |
Keith Owens | 2ba3e3e | 2005-06-30 22:53:00 -0700 | [diff] [blame] | 153 | preempt_enable(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 154 | } |
| 155 | return err; |
| 156 | } |
| 157 | |
| 158 | int |
| 159 | copy_siginfo_to_user (siginfo_t __user *to, siginfo_t *from) |
| 160 | { |
| 161 | if (!access_ok(VERIFY_WRITE, to, sizeof(siginfo_t))) |
| 162 | return -EFAULT; |
| 163 | if (from->si_code < 0) { |
| 164 | if (__copy_to_user(to, from, sizeof(siginfo_t))) |
| 165 | return -EFAULT; |
| 166 | return 0; |
| 167 | } else { |
| 168 | int err; |
| 169 | |
| 170 | /* |
| 171 | * If you change siginfo_t structure, please be sure this code is fixed |
| 172 | * accordingly. It should never copy any pad contained in the structure |
| 173 | * to avoid security leaks, but must copy the generic 3 ints plus the |
| 174 | * relevant union member. |
| 175 | */ |
| 176 | err = __put_user(from->si_signo, &to->si_signo); |
| 177 | err |= __put_user(from->si_errno, &to->si_errno); |
| 178 | err |= __put_user((short)from->si_code, &to->si_code); |
| 179 | switch (from->si_code >> 16) { |
| 180 | case __SI_FAULT >> 16: |
| 181 | err |= __put_user(from->si_flags, &to->si_flags); |
| 182 | err |= __put_user(from->si_isr, &to->si_isr); |
| 183 | case __SI_POLL >> 16: |
| 184 | err |= __put_user(from->si_addr, &to->si_addr); |
| 185 | err |= __put_user(from->si_imm, &to->si_imm); |
| 186 | break; |
| 187 | case __SI_TIMER >> 16: |
| 188 | err |= __put_user(from->si_tid, &to->si_tid); |
| 189 | err |= __put_user(from->si_overrun, &to->si_overrun); |
| 190 | err |= __put_user(from->si_ptr, &to->si_ptr); |
| 191 | break; |
| 192 | case __SI_RT >> 16: /* Not generated by the kernel as of now. */ |
| 193 | case __SI_MESGQ >> 16: |
| 194 | err |= __put_user(from->si_uid, &to->si_uid); |
| 195 | err |= __put_user(from->si_pid, &to->si_pid); |
| 196 | err |= __put_user(from->si_ptr, &to->si_ptr); |
| 197 | break; |
| 198 | case __SI_CHLD >> 16: |
| 199 | err |= __put_user(from->si_utime, &to->si_utime); |
| 200 | err |= __put_user(from->si_stime, &to->si_stime); |
| 201 | err |= __put_user(from->si_status, &to->si_status); |
| 202 | default: |
| 203 | err |= __put_user(from->si_uid, &to->si_uid); |
| 204 | err |= __put_user(from->si_pid, &to->si_pid); |
| 205 | break; |
| 206 | } |
| 207 | return err; |
| 208 | } |
| 209 | } |
| 210 | |
| 211 | long |
| 212 | ia64_rt_sigreturn (struct sigscratch *scr) |
| 213 | { |
| 214 | extern char ia64_strace_leave_kernel, ia64_leave_kernel; |
| 215 | struct sigcontext __user *sc; |
| 216 | struct siginfo si; |
| 217 | sigset_t set; |
| 218 | long retval; |
| 219 | |
| 220 | sc = &((struct sigframe __user *) (scr->pt.r12 + 16))->sc; |
| 221 | |
| 222 | /* |
| 223 | * When we return to the previously executing context, r8 and r10 have already |
| 224 | * been setup the way we want them. Indeed, if the signal wasn't delivered while |
| 225 | * in a system call, we must not touch r8 or r10 as otherwise user-level state |
| 226 | * could be corrupted. |
| 227 | */ |
| 228 | retval = (long) &ia64_leave_kernel; |
David Woodhouse | 446b883 | 2005-04-05 17:47:00 -0700 | [diff] [blame] | 229 | if (test_thread_flag(TIF_SYSCALL_TRACE) |
| 230 | || test_thread_flag(TIF_SYSCALL_AUDIT)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 231 | /* |
| 232 | * strace expects to be notified after sigreturn returns even though the |
| 233 | * context to which we return may not be in the middle of a syscall. |
| 234 | * Thus, the return-value that strace displays for sigreturn is |
| 235 | * meaningless. |
| 236 | */ |
| 237 | retval = (long) &ia64_strace_leave_kernel; |
| 238 | |
| 239 | if (!access_ok(VERIFY_READ, sc, sizeof(*sc))) |
| 240 | goto give_sigsegv; |
| 241 | |
| 242 | if (GET_SIGSET(&set, &sc->sc_mask)) |
| 243 | goto give_sigsegv; |
| 244 | |
| 245 | sigdelsetmask(&set, ~_BLOCKABLE); |
| 246 | |
| 247 | spin_lock_irq(¤t->sighand->siglock); |
| 248 | { |
| 249 | current->blocked = set; |
| 250 | recalc_sigpending(); |
| 251 | } |
| 252 | spin_unlock_irq(¤t->sighand->siglock); |
| 253 | |
| 254 | if (restore_sigcontext(sc, scr)) |
| 255 | goto give_sigsegv; |
| 256 | |
| 257 | #if DEBUG_SIG |
| 258 | printk("SIG return (%s:%d): sp=%lx ip=%lx\n", |
| 259 | current->comm, current->pid, scr->pt.r12, scr->pt.cr_iip); |
| 260 | #endif |
| 261 | /* |
| 262 | * It is more difficult to avoid calling this function than to |
| 263 | * call it and ignore errors. |
| 264 | */ |
| 265 | do_sigaltstack(&sc->sc_stack, NULL, scr->pt.r12); |
| 266 | return retval; |
| 267 | |
| 268 | give_sigsegv: |
| 269 | si.si_signo = SIGSEGV; |
| 270 | si.si_errno = 0; |
| 271 | si.si_code = SI_KERNEL; |
| 272 | si.si_pid = current->pid; |
| 273 | si.si_uid = current->uid; |
| 274 | si.si_addr = sc; |
| 275 | force_sig_info(SIGSEGV, &si, current); |
| 276 | return retval; |
| 277 | } |
| 278 | |
| 279 | /* |
| 280 | * This does just the minimum required setup of sigcontext. |
| 281 | * Specifically, it only installs data that is either not knowable at |
| 282 | * the user-level or that gets modified before execution in the |
| 283 | * trampoline starts. Everything else is done at the user-level. |
| 284 | */ |
| 285 | static long |
| 286 | setup_sigcontext (struct sigcontext __user *sc, sigset_t *mask, struct sigscratch *scr) |
| 287 | { |
| 288 | unsigned long flags = 0, ifs, cfm, nat; |
| 289 | long err; |
| 290 | |
| 291 | ifs = scr->pt.cr_ifs; |
| 292 | |
| 293 | if (on_sig_stack((unsigned long) sc)) |
| 294 | flags |= IA64_SC_FLAG_ONSTACK; |
| 295 | if ((ifs & (1UL << 63)) == 0) |
| 296 | /* if cr_ifs doesn't have the valid bit set, we got here through a syscall */ |
| 297 | flags |= IA64_SC_FLAG_IN_SYSCALL; |
| 298 | cfm = ifs & ((1UL << 38) - 1); |
| 299 | ia64_flush_fph(current); |
| 300 | if ((current->thread.flags & IA64_THREAD_FPH_VALID)) { |
| 301 | flags |= IA64_SC_FLAG_FPH_VALID; |
| 302 | __copy_to_user(&sc->sc_fr[32], current->thread.fph, 96*16); |
| 303 | } |
| 304 | |
| 305 | nat = ia64_get_scratch_nat_bits(&scr->pt, scr->scratch_unat); |
| 306 | |
| 307 | err = __put_user(flags, &sc->sc_flags); |
| 308 | err |= __put_user(nat, &sc->sc_nat); |
| 309 | err |= PUT_SIGSET(mask, &sc->sc_mask); |
| 310 | err |= __put_user(cfm, &sc->sc_cfm); |
| 311 | err |= __put_user(scr->pt.cr_ipsr & IA64_PSR_UM, &sc->sc_um); |
| 312 | err |= __put_user(scr->pt.ar_rsc, &sc->sc_ar_rsc); |
| 313 | err |= __put_user(scr->pt.ar_unat, &sc->sc_ar_unat); /* ar.unat */ |
| 314 | err |= __put_user(scr->pt.ar_fpsr, &sc->sc_ar_fpsr); /* ar.fpsr */ |
| 315 | err |= __put_user(scr->pt.ar_pfs, &sc->sc_ar_pfs); |
| 316 | err |= __put_user(scr->pt.pr, &sc->sc_pr); /* predicates */ |
| 317 | err |= __put_user(scr->pt.b0, &sc->sc_br[0]); /* b0 (rp) */ |
| 318 | err |= __put_user(scr->pt.b6, &sc->sc_br[6]); /* b6 */ |
| 319 | err |= __copy_to_user(&sc->sc_gr[1], &scr->pt.r1, 8); /* r1 */ |
| 320 | err |= __copy_to_user(&sc->sc_gr[8], &scr->pt.r8, 4*8); /* r8-r11 */ |
| 321 | err |= __copy_to_user(&sc->sc_gr[12], &scr->pt.r12, 2*8); /* r12-r13 */ |
| 322 | err |= __copy_to_user(&sc->sc_gr[15], &scr->pt.r15, 8); /* r15 */ |
| 323 | err |= __put_user(scr->pt.cr_iip + ia64_psr(&scr->pt)->ri, &sc->sc_ip); |
| 324 | |
| 325 | if (flags & IA64_SC_FLAG_IN_SYSCALL) { |
| 326 | /* Clear scratch registers if the signal interrupted a system call. */ |
| 327 | err |= __put_user(0, &sc->sc_ar_ccv); /* ar.ccv */ |
| 328 | err |= __put_user(0, &sc->sc_br[7]); /* b7 */ |
| 329 | err |= __put_user(0, &sc->sc_gr[14]); /* r14 */ |
| 330 | err |= __clear_user(&sc->sc_ar25, 2*8); /* ar.csd & ar.ssd */ |
| 331 | err |= __clear_user(&sc->sc_gr[2], 2*8); /* r2-r3 */ |
| 332 | err |= __clear_user(&sc->sc_gr[16], 16*8); /* r16-r31 */ |
| 333 | } else { |
| 334 | /* Copy scratch regs to sigcontext if the signal didn't interrupt a syscall. */ |
| 335 | err |= __put_user(scr->pt.ar_ccv, &sc->sc_ar_ccv); /* ar.ccv */ |
| 336 | err |= __put_user(scr->pt.b7, &sc->sc_br[7]); /* b7 */ |
| 337 | err |= __put_user(scr->pt.r14, &sc->sc_gr[14]); /* r14 */ |
| 338 | err |= __copy_to_user(&sc->sc_ar25, &scr->pt.ar_csd, 2*8); /* ar.csd & ar.ssd */ |
| 339 | err |= __copy_to_user(&sc->sc_gr[2], &scr->pt.r2, 2*8); /* r2-r3 */ |
| 340 | err |= __copy_to_user(&sc->sc_gr[16], &scr->pt.r16, 16*8); /* r16-r31 */ |
| 341 | } |
| 342 | return err; |
| 343 | } |
| 344 | |
| 345 | /* |
| 346 | * Check whether the register-backing store is already on the signal stack. |
| 347 | */ |
| 348 | static inline int |
| 349 | rbs_on_sig_stack (unsigned long bsp) |
| 350 | { |
| 351 | return (bsp - current->sas_ss_sp < current->sas_ss_size); |
| 352 | } |
| 353 | |
| 354 | static long |
| 355 | force_sigsegv_info (int sig, void __user *addr) |
| 356 | { |
| 357 | unsigned long flags; |
| 358 | struct siginfo si; |
| 359 | |
| 360 | if (sig == SIGSEGV) { |
| 361 | /* |
| 362 | * Acquiring siglock around the sa_handler-update is almost |
| 363 | * certainly overkill, but this isn't a |
| 364 | * performance-critical path and I'd rather play it safe |
| 365 | * here than having to debug a nasty race if and when |
| 366 | * something changes in kernel/signal.c that would make it |
| 367 | * no longer safe to modify sa_handler without holding the |
| 368 | * lock. |
| 369 | */ |
| 370 | spin_lock_irqsave(¤t->sighand->siglock, flags); |
| 371 | current->sighand->action[sig - 1].sa.sa_handler = SIG_DFL; |
| 372 | spin_unlock_irqrestore(¤t->sighand->siglock, flags); |
| 373 | } |
| 374 | si.si_signo = SIGSEGV; |
| 375 | si.si_errno = 0; |
| 376 | si.si_code = SI_KERNEL; |
| 377 | si.si_pid = current->pid; |
| 378 | si.si_uid = current->uid; |
| 379 | si.si_addr = addr; |
| 380 | force_sig_info(SIGSEGV, &si, current); |
| 381 | return 0; |
| 382 | } |
| 383 | |
| 384 | static long |
| 385 | setup_frame (int sig, struct k_sigaction *ka, siginfo_t *info, sigset_t *set, |
| 386 | struct sigscratch *scr) |
| 387 | { |
| 388 | extern char __kernel_sigtramp[]; |
David Mosberger-Tang | cf20d1e | 2005-11-02 22:40:19 -0800 | [diff] [blame] | 389 | unsigned long tramp_addr, new_rbs = 0, new_sp; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 390 | struct sigframe __user *frame; |
| 391 | long err; |
| 392 | |
David Mosberger-Tang | cf20d1e | 2005-11-02 22:40:19 -0800 | [diff] [blame] | 393 | new_sp = scr->pt.r12; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 394 | tramp_addr = (unsigned long) __kernel_sigtramp; |
David Mosberger-Tang | cf20d1e | 2005-11-02 22:40:19 -0800 | [diff] [blame] | 395 | if ((ka->sa.sa_flags & SA_ONSTACK) && sas_ss_flags(new_sp) == 0) { |
| 396 | new_sp = current->sas_ss_sp + current->sas_ss_size; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 397 | /* |
| 398 | * We need to check for the register stack being on the signal stack |
| 399 | * separately, because it's switched separately (memory stack is switched |
| 400 | * in the kernel, register stack is switched in the signal trampoline). |
| 401 | */ |
| 402 | if (!rbs_on_sig_stack(scr->pt.ar_bspstore)) |
| 403 | new_rbs = (current->sas_ss_sp + sizeof(long) - 1) & ~(sizeof(long) - 1); |
| 404 | } |
David Mosberger-Tang | cf20d1e | 2005-11-02 22:40:19 -0800 | [diff] [blame] | 405 | frame = (void __user *) ((new_sp - sizeof(*frame)) & -STACK_ALIGN); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 406 | |
| 407 | if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) |
| 408 | return force_sigsegv_info(sig, frame); |
| 409 | |
| 410 | err = __put_user(sig, &frame->arg0); |
| 411 | err |= __put_user(&frame->info, &frame->arg1); |
| 412 | err |= __put_user(&frame->sc, &frame->arg2); |
| 413 | err |= __put_user(new_rbs, &frame->sc.sc_rbs_base); |
| 414 | err |= __put_user(0, &frame->sc.sc_loadrs); /* initialize to zero */ |
| 415 | err |= __put_user(ka->sa.sa_handler, &frame->handler); |
| 416 | |
| 417 | err |= copy_siginfo_to_user(&frame->info, info); |
| 418 | |
| 419 | err |= __put_user(current->sas_ss_sp, &frame->sc.sc_stack.ss_sp); |
| 420 | err |= __put_user(current->sas_ss_size, &frame->sc.sc_stack.ss_size); |
| 421 | err |= __put_user(sas_ss_flags(scr->pt.r12), &frame->sc.sc_stack.ss_flags); |
| 422 | err |= setup_sigcontext(&frame->sc, set, scr); |
| 423 | |
| 424 | if (unlikely(err)) |
| 425 | return force_sigsegv_info(sig, frame); |
| 426 | |
| 427 | scr->pt.r12 = (unsigned long) frame - 16; /* new stack pointer */ |
| 428 | scr->pt.ar_fpsr = FPSR_DEFAULT; /* reset fpsr for signal handler */ |
| 429 | scr->pt.cr_iip = tramp_addr; |
| 430 | ia64_psr(&scr->pt)->ri = 0; /* start executing in first slot */ |
| 431 | ia64_psr(&scr->pt)->be = 0; /* force little-endian byte-order */ |
| 432 | /* |
| 433 | * Force the interruption function mask to zero. This has no effect when a |
| 434 | * system-call got interrupted by a signal (since, in that case, scr->pt_cr_ifs is |
| 435 | * ignored), but it has the desirable effect of making it possible to deliver a |
| 436 | * signal with an incomplete register frame (which happens when a mandatory RSE |
| 437 | * load faults). Furthermore, it has no negative effect on the getting the user's |
| 438 | * dirty partition preserved, because that's governed by scr->pt.loadrs. |
| 439 | */ |
| 440 | scr->pt.cr_ifs = (1UL << 63); |
| 441 | |
| 442 | /* |
| 443 | * Note: this affects only the NaT bits of the scratch regs (the ones saved in |
| 444 | * pt_regs), which is exactly what we want. |
| 445 | */ |
| 446 | scr->scratch_unat = 0; /* ensure NaT bits of r12 is clear */ |
| 447 | |
| 448 | #if DEBUG_SIG |
| 449 | printk("SIG deliver (%s:%d): sig=%d sp=%lx ip=%lx handler=%p\n", |
| 450 | current->comm, current->pid, sig, scr->pt.r12, frame->sc.sc_ip, frame->handler); |
| 451 | #endif |
| 452 | return 1; |
| 453 | } |
| 454 | |
| 455 | static long |
| 456 | handle_signal (unsigned long sig, struct k_sigaction *ka, siginfo_t *info, sigset_t *oldset, |
| 457 | struct sigscratch *scr) |
| 458 | { |
| 459 | if (IS_IA32_PROCESS(&scr->pt)) { |
| 460 | /* send signal to IA-32 process */ |
| 461 | if (!ia32_setup_frame1(sig, ka, info, oldset, &scr->pt)) |
| 462 | return 0; |
| 463 | } else |
| 464 | /* send signal to IA-64 process */ |
| 465 | if (!setup_frame(sig, ka, info, oldset, scr)) |
| 466 | return 0; |
| 467 | |
Steven Rostedt | 69be8f1 | 2005-08-29 11:44:09 -0400 | [diff] [blame] | 468 | spin_lock_irq(¤t->sighand->siglock); |
| 469 | sigorsets(¤t->blocked, ¤t->blocked, &ka->sa.sa_mask); |
| 470 | if (!(ka->sa.sa_flags & SA_NODEFER)) |
| 471 | sigaddset(¤t->blocked, sig); |
| 472 | recalc_sigpending(); |
| 473 | spin_unlock_irq(¤t->sighand->siglock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 474 | return 1; |
| 475 | } |
| 476 | |
| 477 | /* |
| 478 | * Note that `init' is a special process: it doesn't get signals it doesn't want to |
| 479 | * handle. Thus you cannot kill init even with a SIGKILL even by mistake. |
| 480 | */ |
| 481 | long |
| 482 | ia64_do_signal (sigset_t *oldset, struct sigscratch *scr, long in_syscall) |
| 483 | { |
| 484 | struct k_sigaction ka; |
| 485 | siginfo_t info; |
| 486 | long restart = in_syscall; |
| 487 | long errno = scr->pt.r8; |
| 488 | # define ERR_CODE(c) (IS_IA32_PROCESS(&scr->pt) ? -(c) : (c)) |
| 489 | |
| 490 | /* |
| 491 | * In the ia64_leave_kernel code path, we want the common case to go fast, which |
| 492 | * is why we may in certain cases get here from kernel mode. Just return without |
| 493 | * doing anything if so. |
| 494 | */ |
| 495 | if (!user_mode(&scr->pt)) |
| 496 | return 0; |
| 497 | |
| 498 | if (!oldset) |
| 499 | oldset = ¤t->blocked; |
| 500 | |
| 501 | /* |
| 502 | * This only loops in the rare cases of handle_signal() failing, in which case we |
| 503 | * need to push through a forced SIGSEGV. |
| 504 | */ |
| 505 | while (1) { |
| 506 | int signr = get_signal_to_deliver(&info, &ka, &scr->pt, NULL); |
| 507 | |
| 508 | /* |
| 509 | * get_signal_to_deliver() may have run a debugger (via notify_parent()) |
| 510 | * and the debugger may have modified the state (e.g., to arrange for an |
| 511 | * inferior call), thus it's important to check for restarting _after_ |
| 512 | * get_signal_to_deliver(). |
| 513 | */ |
| 514 | if (IS_IA32_PROCESS(&scr->pt)) { |
| 515 | if (in_syscall) { |
| 516 | if (errno >= 0) |
| 517 | restart = 0; |
| 518 | else |
| 519 | errno = -errno; |
| 520 | } |
| 521 | } else if ((long) scr->pt.r10 != -1) |
| 522 | /* |
| 523 | * A system calls has to be restarted only if one of the error codes |
| 524 | * ERESTARTNOHAND, ERESTARTSYS, or ERESTARTNOINTR is returned. If r10 |
| 525 | * isn't -1 then r8 doesn't hold an error code and we don't need to |
| 526 | * restart the syscall, so we can clear the "restart" flag here. |
| 527 | */ |
| 528 | restart = 0; |
| 529 | |
| 530 | if (signr <= 0) |
| 531 | break; |
| 532 | |
| 533 | if (unlikely(restart)) { |
| 534 | switch (errno) { |
| 535 | case ERESTART_RESTARTBLOCK: |
| 536 | case ERESTARTNOHAND: |
| 537 | scr->pt.r8 = ERR_CODE(EINTR); |
| 538 | /* note: scr->pt.r10 is already -1 */ |
| 539 | break; |
| 540 | |
| 541 | case ERESTARTSYS: |
| 542 | if ((ka.sa.sa_flags & SA_RESTART) == 0) { |
| 543 | scr->pt.r8 = ERR_CODE(EINTR); |
| 544 | /* note: scr->pt.r10 is already -1 */ |
| 545 | break; |
| 546 | } |
| 547 | case ERESTARTNOINTR: |
| 548 | if (IS_IA32_PROCESS(&scr->pt)) { |
| 549 | scr->pt.r8 = scr->pt.r1; |
| 550 | scr->pt.cr_iip -= 2; |
| 551 | } else |
| 552 | ia64_decrement_ip(&scr->pt); |
| 553 | restart = 0; /* don't restart twice if handle_signal() fails... */ |
| 554 | } |
| 555 | } |
| 556 | |
| 557 | /* |
| 558 | * Whee! Actually deliver the signal. If the delivery failed, we need to |
| 559 | * continue to iterate in this loop so we can deliver the SIGSEGV... |
| 560 | */ |
| 561 | if (handle_signal(signr, &ka, &info, oldset, scr)) |
| 562 | return 1; |
| 563 | } |
| 564 | |
| 565 | /* Did we come from a system call? */ |
| 566 | if (restart) { |
| 567 | /* Restart the system call - no handlers present */ |
| 568 | if (errno == ERESTARTNOHAND || errno == ERESTARTSYS || errno == ERESTARTNOINTR |
| 569 | || errno == ERESTART_RESTARTBLOCK) |
| 570 | { |
| 571 | if (IS_IA32_PROCESS(&scr->pt)) { |
| 572 | scr->pt.r8 = scr->pt.r1; |
| 573 | scr->pt.cr_iip -= 2; |
| 574 | if (errno == ERESTART_RESTARTBLOCK) |
| 575 | scr->pt.r8 = 0; /* x86 version of __NR_restart_syscall */ |
| 576 | } else { |
| 577 | /* |
| 578 | * Note: the syscall number is in r15 which is saved in |
| 579 | * pt_regs so all we need to do here is adjust ip so that |
| 580 | * the "break" instruction gets re-executed. |
| 581 | */ |
| 582 | ia64_decrement_ip(&scr->pt); |
| 583 | if (errno == ERESTART_RESTARTBLOCK) |
| 584 | scr->pt.r15 = __NR_restart_syscall; |
| 585 | } |
| 586 | } |
| 587 | } |
| 588 | return 0; |
| 589 | } |