| /* |
| * Copyright (C) 2003 PathScale, Inc. |
| * Licensed under the GPL |
| */ |
| |
| #include "linux/personality.h" |
| #include "linux/ptrace.h" |
| #include "asm/unistd.h" |
| #include "asm/uaccess.h" |
| #include "asm/ucontext.h" |
| #include "frame_kern.h" |
| #include "skas.h" |
| |
| void copy_sc(struct uml_pt_regs *regs, void *from) |
| { |
| struct sigcontext *sc = from; |
| |
| #define GETREG(regs, regno, sc, regname) \ |
| (regs)->gp[(regno) / sizeof(unsigned long)] = (sc)->regname |
| |
| GETREG(regs, R8, sc, r8); |
| GETREG(regs, R9, sc, r9); |
| GETREG(regs, R10, sc, r10); |
| GETREG(regs, R11, sc, r11); |
| GETREG(regs, R12, sc, r12); |
| GETREG(regs, R13, sc, r13); |
| GETREG(regs, R14, sc, r14); |
| GETREG(regs, R15, sc, r15); |
| GETREG(regs, RDI, sc, rdi); |
| GETREG(regs, RSI, sc, rsi); |
| GETREG(regs, RBP, sc, rbp); |
| GETREG(regs, RBX, sc, rbx); |
| GETREG(regs, RDX, sc, rdx); |
| GETREG(regs, RAX, sc, rax); |
| GETREG(regs, RCX, sc, rcx); |
| GETREG(regs, RSP, sc, rsp); |
| GETREG(regs, RIP, sc, rip); |
| GETREG(regs, EFLAGS, sc, eflags); |
| GETREG(regs, CS, sc, cs); |
| |
| #undef GETREG |
| } |
| |
| static int copy_sc_from_user(struct pt_regs *regs, |
| struct sigcontext __user *from, |
| struct _fpstate __user *fpp) |
| { |
| struct user_i387_struct fp; |
| int err = 0; |
| |
| #define GETREG(regs, regno, sc, regname) \ |
| __get_user((regs)->regs.gp[(regno) / sizeof(unsigned long)], \ |
| &(sc)->regname) |
| |
| err |= GETREG(regs, R8, from, r8); |
| err |= GETREG(regs, R9, from, r9); |
| err |= GETREG(regs, R10, from, r10); |
| err |= GETREG(regs, R11, from, r11); |
| err |= GETREG(regs, R12, from, r12); |
| err |= GETREG(regs, R13, from, r13); |
| err |= GETREG(regs, R14, from, r14); |
| err |= GETREG(regs, R15, from, r15); |
| err |= GETREG(regs, RDI, from, rdi); |
| err |= GETREG(regs, RSI, from, rsi); |
| err |= GETREG(regs, RBP, from, rbp); |
| err |= GETREG(regs, RBX, from, rbx); |
| err |= GETREG(regs, RDX, from, rdx); |
| err |= GETREG(regs, RAX, from, rax); |
| err |= GETREG(regs, RCX, from, rcx); |
| err |= GETREG(regs, RSP, from, rsp); |
| err |= GETREG(regs, RIP, from, rip); |
| err |= GETREG(regs, EFLAGS, from, eflags); |
| err |= GETREG(regs, CS, from, cs); |
| if (err) |
| return 1; |
| |
| #undef GETREG |
| |
| err = copy_from_user(&fp, fpp, sizeof(struct user_i387_struct)); |
| if (err) |
| return 1; |
| |
| err = restore_fp_registers(userspace_pid[current_thread->cpu], |
| (unsigned long *) &fp); |
| if (err < 0) { |
| printk(KERN_ERR "copy_sc_from_user - " |
| "restore_fp_registers failed, errno = %d\n", |
| -err); |
| return 1; |
| } |
| |
| return 0; |
| } |
| |
| static int copy_sc_to_user(struct sigcontext __user *to, |
| struct _fpstate __user *to_fp, struct pt_regs *regs, |
| unsigned long mask, unsigned long sp) |
| { |
| struct faultinfo * fi = ¤t->thread.arch.faultinfo; |
| struct user_i387_struct fp; |
| int err = 0; |
| |
| err |= __put_user(0, &to->gs); |
| err |= __put_user(0, &to->fs); |
| |
| #define PUTREG(regs, regno, sc, regname) \ |
| __put_user((regs)->regs.gp[(regno) / sizeof(unsigned long)], \ |
| &(sc)->regname) |
| |
| err |= PUTREG(regs, RDI, to, rdi); |
| err |= PUTREG(regs, RSI, to, rsi); |
| err |= PUTREG(regs, RBP, to, rbp); |
| /* Must use orignal RSP, which is passed in, rather than what's in |
| * the pt_regs, because that's already been updated to point at the |
| * signal frame. |
| */ |
| err |= __put_user(sp, &to->rsp); |
| err |= PUTREG(regs, RBX, to, rbx); |
| err |= PUTREG(regs, RDX, to, rdx); |
| err |= PUTREG(regs, RCX, to, rcx); |
| err |= PUTREG(regs, RAX, to, rax); |
| err |= PUTREG(regs, R8, to, r8); |
| err |= PUTREG(regs, R9, to, r9); |
| err |= PUTREG(regs, R10, to, r10); |
| err |= PUTREG(regs, R11, to, r11); |
| err |= PUTREG(regs, R12, to, r12); |
| err |= PUTREG(regs, R13, to, r13); |
| err |= PUTREG(regs, R14, to, r14); |
| err |= PUTREG(regs, R15, to, r15); |
| err |= PUTREG(regs, CS, to, cs); /* XXX x86_64 doesn't do this */ |
| |
| err |= __put_user(fi->cr2, &to->cr2); |
| err |= __put_user(fi->error_code, &to->err); |
| err |= __put_user(fi->trap_no, &to->trapno); |
| |
| err |= PUTREG(regs, RIP, to, rip); |
| err |= PUTREG(regs, EFLAGS, to, eflags); |
| #undef PUTREG |
| |
| err |= __put_user(mask, &to->oldmask); |
| if (err) |
| return 1; |
| |
| err = save_fp_registers(userspace_pid[current_thread->cpu], |
| (unsigned long *) &fp); |
| if (err < 0) { |
| printk(KERN_ERR "copy_sc_from_user - restore_fp_registers " |
| "failed, errno = %d\n", -err); |
| return 1; |
| } |
| |
| if (copy_to_user(to_fp, &fp, sizeof(struct user_i387_struct))) |
| return 1; |
| |
| return(err); |
| } |
| |
| struct rt_sigframe |
| { |
| char __user *pretcode; |
| struct ucontext uc; |
| struct siginfo info; |
| struct _fpstate fpstate; |
| }; |
| |
| #define round_down(m, n) (((m) / (n)) * (n)) |
| |
| int setup_signal_stack_si(unsigned long stack_top, int sig, |
| struct k_sigaction *ka, struct pt_regs * regs, |
| siginfo_t *info, sigset_t *set) |
| { |
| struct rt_sigframe __user *frame; |
| unsigned long save_sp = PT_REGS_RSP(regs); |
| int err = 0; |
| struct task_struct *me = current; |
| |
| frame = (struct rt_sigframe __user *) |
| round_down(stack_top - sizeof(struct rt_sigframe), 16); |
| /* Subtract 128 for a red zone and 8 for proper alignment */ |
| frame = (struct rt_sigframe __user *) ((unsigned long) frame - 128 - 8); |
| |
| if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) |
| goto out; |
| |
| if (ka->sa.sa_flags & SA_SIGINFO) { |
| err |= copy_siginfo_to_user(&frame->info, info); |
| if (err) |
| goto out; |
| } |
| |
| /* Update SP now because the page fault handler refuses to extend |
| * the stack if the faulting address is too far below the current |
| * SP, which frame now certainly is. If there's an error, the original |
| * value is restored on the way out. |
| * When writing the sigcontext to the stack, we have to write the |
| * original value, so that's passed to copy_sc_to_user, which does |
| * the right thing with it. |
| */ |
| PT_REGS_RSP(regs) = (unsigned long) frame; |
| |
| /* Create the ucontext. */ |
| err |= __put_user(0, &frame->uc.uc_flags); |
| err |= __put_user(0, &frame->uc.uc_link); |
| err |= __put_user(me->sas_ss_sp, &frame->uc.uc_stack.ss_sp); |
| err |= __put_user(sas_ss_flags(save_sp), |
| &frame->uc.uc_stack.ss_flags); |
| err |= __put_user(me->sas_ss_size, &frame->uc.uc_stack.ss_size); |
| err |= copy_sc_to_user(&frame->uc.uc_mcontext, &frame->fpstate, regs, |
| set->sig[0], save_sp); |
| err |= __put_user(&frame->fpstate, &frame->uc.uc_mcontext.fpstate); |
| if (sizeof(*set) == 16) { |
| __put_user(set->sig[0], &frame->uc.uc_sigmask.sig[0]); |
| __put_user(set->sig[1], &frame->uc.uc_sigmask.sig[1]); |
| } |
| else |
| err |= __copy_to_user(&frame->uc.uc_sigmask, set, |
| sizeof(*set)); |
| |
| /* Set up to return from userspace. If provided, use a stub |
| already in userspace. */ |
| /* x86-64 should always use SA_RESTORER. */ |
| if (ka->sa.sa_flags & SA_RESTORER) |
| err |= __put_user(ka->sa.sa_restorer, &frame->pretcode); |
| else |
| /* could use a vstub here */ |
| goto restore_sp; |
| |
| if (err) |
| goto restore_sp; |
| |
| /* Set up registers for signal handler */ |
| { |
| struct exec_domain *ed = current_thread_info()->exec_domain; |
| if (unlikely(ed && ed->signal_invmap && sig < 32)) |
| sig = ed->signal_invmap[sig]; |
| } |
| |
| PT_REGS_RDI(regs) = sig; |
| /* In case the signal handler was declared without prototypes */ |
| PT_REGS_RAX(regs) = 0; |
| |
| /* This also works for non SA_SIGINFO handlers because they expect the |
| next argument after the signal number on the stack. */ |
| PT_REGS_RSI(regs) = (unsigned long) &frame->info; |
| PT_REGS_RDX(regs) = (unsigned long) &frame->uc; |
| PT_REGS_RIP(regs) = (unsigned long) ka->sa.sa_handler; |
| out: |
| return err; |
| |
| restore_sp: |
| PT_REGS_RSP(regs) = save_sp; |
| return err; |
| } |
| |
| long sys_rt_sigreturn(struct pt_regs *regs) |
| { |
| unsigned long sp = PT_REGS_SP(¤t->thread.regs); |
| struct rt_sigframe __user *frame = |
| (struct rt_sigframe __user *)(sp - 8); |
| struct ucontext __user *uc = &frame->uc; |
| sigset_t set; |
| |
| if (copy_from_user(&set, &uc->uc_sigmask, sizeof(set))) |
| goto segfault; |
| |
| sigdelsetmask(&set, ~_BLOCKABLE); |
| |
| spin_lock_irq(¤t->sighand->siglock); |
| current->blocked = set; |
| recalc_sigpending(); |
| spin_unlock_irq(¤t->sighand->siglock); |
| |
| if (copy_sc_from_user(¤t->thread.regs, &uc->uc_mcontext, |
| &frame->fpstate)) |
| goto segfault; |
| |
| /* Avoid ERESTART handling */ |
| PT_REGS_SYSCALL_NR(¤t->thread.regs) = -1; |
| return(PT_REGS_SYSCALL_RET(¤t->thread.regs)); |
| |
| segfault: |
| force_sig(SIGSEGV, current); |
| return 0; |
| } |