diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/x86_64/ia32/ia32_signal.c |
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'arch/x86_64/ia32/ia32_signal.c')
-rw-r--r-- | arch/x86_64/ia32/ia32_signal.c | 621 |
1 files changed, 621 insertions, 0 deletions
diff --git a/arch/x86_64/ia32/ia32_signal.c b/arch/x86_64/ia32/ia32_signal.c new file mode 100644 index 00000000000..fbd09b5126c --- /dev/null +++ b/arch/x86_64/ia32/ia32_signal.c @@ -0,0 +1,621 @@ +/* + * linux/arch/x86_64/ia32/ia32_signal.c + * + * Copyright (C) 1991, 1992 Linus Torvalds + * + * 1997-11-28 Modified for POSIX.1b signals by Richard Henderson + * 2000-06-20 Pentium III FXSR, SSE support by Gareth Hughes + * 2000-12-* x86-64 compatibility mode signal handling by Andi Kleen + * + * $Id: ia32_signal.c,v 1.22 2002/07/29 10:34:03 ak Exp $ + */ + +#include <linux/sched.h> +#include <linux/mm.h> +#include <linux/smp.h> +#include <linux/smp_lock.h> +#include <linux/kernel.h> +#include <linux/signal.h> +#include <linux/errno.h> +#include <linux/wait.h> +#include <linux/ptrace.h> +#include <linux/unistd.h> +#include <linux/stddef.h> +#include <linux/personality.h> +#include <linux/compat.h> +#include <asm/ucontext.h> +#include <asm/uaccess.h> +#include <asm/i387.h> +#include <asm/ia32.h> +#include <asm/ptrace.h> +#include <asm/ia32_unistd.h> +#include <asm/user32.h> +#include <asm/sigcontext32.h> +#include <asm/fpu32.h> +#include <asm/proto.h> +#include <asm/vsyscall32.h> + +#define DEBUG_SIG 0 + +#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP))) + +asmlinkage int do_signal(struct pt_regs *regs, sigset_t *oldset); +void signal_fault(struct pt_regs *regs, void __user *frame, char *where); + +int copy_siginfo_to_user32(compat_siginfo_t __user *to, siginfo_t *from) +{ + int err; + if (!access_ok (VERIFY_WRITE, to, sizeof(compat_siginfo_t))) + return -EFAULT; + + /* If you change siginfo_t structure, please make sure that + this code is fixed accordingly. + It should never copy any pad contained in the structure + to avoid security leaks, but must copy the generic + 3 ints plus the relevant union member. */ + err = __put_user(from->si_signo, &to->si_signo); + err |= __put_user(from->si_errno, &to->si_errno); + err |= __put_user((short)from->si_code, &to->si_code); + + if (from->si_code < 0) { + err |= __put_user(from->si_pid, &to->si_pid); + err |= __put_user(from->si_uid, &to->si_uid); + err |= __put_user(ptr_to_compat(from->si_ptr), &to->si_ptr); + } else { + /* First 32bits of unions are always present: + * si_pid === si_band === si_tid === si_addr(LS half) */ + err |= __put_user(from->_sifields._pad[0], &to->_sifields._pad[0]); + switch (from->si_code >> 16) { + case __SI_FAULT >> 16: + break; + case __SI_CHLD >> 16: + err |= __put_user(from->si_utime, &to->si_utime); + err |= __put_user(from->si_stime, &to->si_stime); + err |= __put_user(from->si_status, &to->si_status); + /* FALL THROUGH */ + default: + case __SI_KILL >> 16: + err |= __put_user(from->si_uid, &to->si_uid); + break; + case __SI_POLL >> 16: + err |= __put_user(from->si_fd, &to->si_fd); + break; + case __SI_TIMER >> 16: + err |= __put_user(from->si_overrun, &to->si_overrun); + err |= __put_user(ptr_to_compat(from->si_ptr), + &to->si_ptr); + break; + case __SI_RT >> 16: /* This is not generated by the kernel as of now. */ + case __SI_MESGQ >> 16: + err |= __put_user(from->si_uid, &to->si_uid); + err |= __put_user(from->si_int, &to->si_int); + break; + } + } + return err; +} + +int copy_siginfo_from_user32(siginfo_t *to, compat_siginfo_t __user *from) +{ + int err; + u32 ptr32; + if (!access_ok (VERIFY_READ, from, sizeof(compat_siginfo_t))) + return -EFAULT; + + err = __get_user(to->si_signo, &from->si_signo); + err |= __get_user(to->si_errno, &from->si_errno); + err |= __get_user(to->si_code, &from->si_code); + + err |= __get_user(to->si_pid, &from->si_pid); + err |= __get_user(to->si_uid, &from->si_uid); + err |= __get_user(ptr32, &from->si_ptr); + to->si_ptr = compat_ptr(ptr32); + + return err; +} + +asmlinkage long +sys32_sigsuspend(int history0, int history1, old_sigset_t mask, + struct pt_regs *regs) +{ + sigset_t saveset; + + mask &= _BLOCKABLE; + spin_lock_irq(¤t->sighand->siglock); + saveset = current->blocked; + siginitset(¤t->blocked, mask); + recalc_sigpending(); + spin_unlock_irq(¤t->sighand->siglock); + + regs->rax = -EINTR; + while (1) { + current->state = TASK_INTERRUPTIBLE; + schedule(); + if (do_signal(regs, &saveset)) + return -EINTR; + } +} + +asmlinkage long +sys32_sigaltstack(const stack_ia32_t __user *uss_ptr, + stack_ia32_t __user *uoss_ptr, + struct pt_regs *regs) +{ + stack_t uss,uoss; + int ret; + mm_segment_t seg; + if (uss_ptr) { + u32 ptr; + memset(&uss,0,sizeof(stack_t)); + if (!access_ok(VERIFY_READ,uss_ptr,sizeof(stack_ia32_t)) || + __get_user(ptr, &uss_ptr->ss_sp) || + __get_user(uss.ss_flags, &uss_ptr->ss_flags) || + __get_user(uss.ss_size, &uss_ptr->ss_size)) + return -EFAULT; + uss.ss_sp = compat_ptr(ptr); + } + seg = get_fs(); + set_fs(KERNEL_DS); + ret = do_sigaltstack(uss_ptr ? &uss : NULL, &uoss, regs->rsp); + set_fs(seg); + if (ret >= 0 && uoss_ptr) { + if (!access_ok(VERIFY_WRITE,uoss_ptr,sizeof(stack_ia32_t)) || + __put_user(ptr_to_compat(uoss.ss_sp), &uoss_ptr->ss_sp) || + __put_user(uoss.ss_flags, &uoss_ptr->ss_flags) || + __put_user(uoss.ss_size, &uoss_ptr->ss_size)) + ret = -EFAULT; + } + return ret; +} + +/* + * Do a signal return; undo the signal stack. + */ + +struct sigframe +{ + u32 pretcode; + int sig; + struct sigcontext_ia32 sc; + struct _fpstate_ia32 fpstate; + unsigned int extramask[_COMPAT_NSIG_WORDS-1]; + char retcode[8]; +}; + +struct rt_sigframe +{ + u32 pretcode; + int sig; + u32 pinfo; + u32 puc; + compat_siginfo_t info; + struct ucontext_ia32 uc; + struct _fpstate_ia32 fpstate; + char retcode[8]; +}; + +static int +ia32_restore_sigcontext(struct pt_regs *regs, struct sigcontext_ia32 __user *sc, unsigned int *peax) +{ + unsigned int err = 0; + + /* Always make any pending restarted system calls return -EINTR */ + current_thread_info()->restart_block.fn = do_no_restart_syscall; + +#if DEBUG_SIG + printk("SIG restore_sigcontext: sc=%p err(%x) eip(%x) cs(%x) flg(%x)\n", + sc, sc->err, sc->eip, sc->cs, sc->eflags); +#endif +#define COPY(x) { \ + unsigned int reg; \ + err |= __get_user(reg, &sc->e ##x); \ + regs->r ## x = reg; \ +} + +#define RELOAD_SEG(seg,mask) \ + { unsigned int cur; \ + unsigned short pre; \ + err |= __get_user(pre, &sc->seg); \ + asm volatile("movl %%" #seg ",%0" : "=r" (cur)); \ + pre |= mask; \ + if (pre != cur) loadsegment(seg,pre); } + + /* Reload fs and gs if they have changed in the signal handler. + This does not handle long fs/gs base changes in the handler, but + does not clobber them at least in the normal case. */ + + { + unsigned gs, oldgs; + err |= __get_user(gs, &sc->gs); + gs |= 3; + asm("movl %%gs,%0" : "=r" (oldgs)); + if (gs != oldgs) + load_gs_index(gs); + } + RELOAD_SEG(fs,3); + RELOAD_SEG(ds,3); + RELOAD_SEG(es,3); + + COPY(di); COPY(si); COPY(bp); COPY(sp); COPY(bx); + COPY(dx); COPY(cx); COPY(ip); + /* Don't touch extended registers */ + + err |= __get_user(regs->cs, &sc->cs); + regs->cs |= 3; + err |= __get_user(regs->ss, &sc->ss); + regs->ss |= 3; + + { + unsigned int tmpflags; + err |= __get_user(tmpflags, &sc->eflags); + regs->eflags = (regs->eflags & ~0x40DD5) | (tmpflags & 0x40DD5); + regs->orig_rax = -1; /* disable syscall checks */ + } + + { + u32 tmp; + struct _fpstate_ia32 __user * buf; + err |= __get_user(tmp, &sc->fpstate); + buf = compat_ptr(tmp); + if (buf) { + if (!access_ok(VERIFY_READ, buf, sizeof(*buf))) + goto badframe; + err |= restore_i387_ia32(current, buf, 0); + } else { + struct task_struct *me = current; + if (used_math()) { + clear_fpu(me); + clear_used_math(); + } + } + } + + { + u32 tmp; + err |= __get_user(tmp, &sc->eax); + *peax = tmp; + } + return err; + +badframe: + return 1; +} + +asmlinkage long sys32_sigreturn(struct pt_regs *regs) +{ + struct sigframe __user *frame = (struct sigframe __user *)(regs->rsp-8); + sigset_t set; + unsigned int eax; + + if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) + goto badframe; + if (__get_user(set.sig[0], &frame->sc.oldmask) + || (_COMPAT_NSIG_WORDS > 1 + && __copy_from_user((((char *) &set.sig) + 4), &frame->extramask, + sizeof(frame->extramask)))) + goto badframe; + + sigdelsetmask(&set, ~_BLOCKABLE); + spin_lock_irq(¤t->sighand->siglock); + current->blocked = set; + recalc_sigpending(); + spin_unlock_irq(¤t->sighand->siglock); + + if (ia32_restore_sigcontext(regs, &frame->sc, &eax)) + goto badframe; + return eax; + +badframe: + signal_fault(regs, frame, "32bit sigreturn"); + return 0; +} + +asmlinkage long sys32_rt_sigreturn(struct pt_regs *regs) +{ + struct rt_sigframe __user *frame; + sigset_t set; + unsigned int eax; + struct pt_regs tregs; + + frame = (struct rt_sigframe __user *)(regs->rsp - 4); + + if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) + goto badframe; + if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) + goto badframe; + + sigdelsetmask(&set, ~_BLOCKABLE); + spin_lock_irq(¤t->sighand->siglock); + current->blocked = set; + recalc_sigpending(); + spin_unlock_irq(¤t->sighand->siglock); + + if (ia32_restore_sigcontext(regs, &frame->uc.uc_mcontext, &eax)) + goto badframe; + + tregs = *regs; + if (sys32_sigaltstack(&frame->uc.uc_stack, NULL, &tregs) == -EFAULT) + goto badframe; + + return eax; + +badframe: + signal_fault(regs,frame,"32bit rt sigreturn"); + return 0; +} + +/* + * Set up a signal frame. + */ + +static int +ia32_setup_sigcontext(struct sigcontext_ia32 __user *sc, struct _fpstate_ia32 __user *fpstate, + struct pt_regs *regs, unsigned int mask) +{ + int tmp, err = 0; + u32 eflags; + + tmp = 0; + __asm__("movl %%gs,%0" : "=r"(tmp): "0"(tmp)); + err |= __put_user(tmp, (unsigned int __user *)&sc->gs); + __asm__("movl %%fs,%0" : "=r"(tmp): "0"(tmp)); + err |= __put_user(tmp, (unsigned int __user *)&sc->fs); + __asm__("movl %%ds,%0" : "=r"(tmp): "0"(tmp)); + err |= __put_user(tmp, (unsigned int __user *)&sc->ds); + __asm__("movl %%es,%0" : "=r"(tmp): "0"(tmp)); + err |= __put_user(tmp, (unsigned int __user *)&sc->es); + + err |= __put_user((u32)regs->rdi, &sc->edi); + err |= __put_user((u32)regs->rsi, &sc->esi); + err |= __put_user((u32)regs->rbp, &sc->ebp); + err |= __put_user((u32)regs->rsp, &sc->esp); + err |= __put_user((u32)regs->rbx, &sc->ebx); + err |= __put_user((u32)regs->rdx, &sc->edx); + err |= __put_user((u32)regs->rcx, &sc->ecx); + err |= __put_user((u32)regs->rax, &sc->eax); + err |= __put_user((u32)regs->cs, &sc->cs); + err |= __put_user((u32)regs->ss, &sc->ss); + err |= __put_user(current->thread.trap_no, &sc->trapno); + err |= __put_user(current->thread.error_code, &sc->err); + err |= __put_user((u32)regs->rip, &sc->eip); + eflags = regs->eflags; + if (current->ptrace & PT_PTRACED) + eflags &= ~TF_MASK; + err |= __put_user((u32)eflags, &sc->eflags); + err |= __put_user((u32)regs->rsp, &sc->esp_at_signal); + + tmp = save_i387_ia32(current, fpstate, regs, 0); + if (tmp < 0) + err = -EFAULT; + else { + clear_used_math(); + stts(); + err |= __put_user(ptr_to_compat(tmp ? fpstate : NULL), + &sc->fpstate); + } + + /* non-iBCS2 extensions.. */ + err |= __put_user(mask, &sc->oldmask); + err |= __put_user(current->thread.cr2, &sc->cr2); + + return err; +} + +/* + * Determine which stack to use.. + */ +static void __user * +get_sigframe(struct k_sigaction *ka, struct pt_regs * regs, size_t frame_size) +{ + unsigned long rsp; + + /* Default to using normal stack */ + rsp = regs->rsp; + + /* This is the X/Open sanctioned signal stack switching. */ + if (ka->sa.sa_flags & SA_ONSTACK) { + if (sas_ss_flags(rsp) == 0) + rsp = current->sas_ss_sp + current->sas_ss_size; + } + + /* This is the legacy signal stack switching. */ + else if ((regs->ss & 0xffff) != __USER_DS && + !(ka->sa.sa_flags & SA_RESTORER) && + ka->sa.sa_restorer) { + rsp = (unsigned long) ka->sa.sa_restorer; + } + + return (void __user *)((rsp - frame_size) & -8UL); +} + +void ia32_setup_frame(int sig, struct k_sigaction *ka, + compat_sigset_t *set, struct pt_regs * regs) +{ + struct sigframe __user *frame; + int err = 0; + + frame = get_sigframe(ka, regs, sizeof(*frame)); + + if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) + goto give_sigsegv; + + { + struct exec_domain *ed = current_thread_info()->exec_domain; + err |= __put_user((ed + && ed->signal_invmap + && sig < 32 + ? ed->signal_invmap[sig] + : sig), + &frame->sig); + } + if (err) + goto give_sigsegv; + + err |= ia32_setup_sigcontext(&frame->sc, &frame->fpstate, regs, + set->sig[0]); + if (err) + goto give_sigsegv; + + if (_COMPAT_NSIG_WORDS > 1) { + err |= __copy_to_user(frame->extramask, &set->sig[1], + sizeof(frame->extramask)); + } + if (err) + goto give_sigsegv; + + /* Return stub is in 32bit vsyscall page */ + { + void __user *restorer = VSYSCALL32_SIGRETURN; + if (ka->sa.sa_flags & SA_RESTORER) + restorer = ka->sa.sa_restorer; + err |= __put_user(ptr_to_compat(restorer), &frame->pretcode); + } + /* These are actually not used anymore, but left because some + gdb versions depend on them as a marker. */ + { + /* copy_to_user optimizes that into a single 8 byte store */ + static const struct { + u16 poplmovl; + u32 val; + u16 int80; + u16 pad; + } __attribute__((packed)) code = { + 0xb858, /* popl %eax ; movl $...,%eax */ + __NR_ia32_sigreturn, + 0x80cd, /* int $0x80 */ + 0, + }; + err |= __copy_to_user(frame->retcode, &code, 8); + } + if (err) + goto give_sigsegv; + + /* Set up registers for signal handler */ + regs->rsp = (unsigned long) frame; + regs->rip = (unsigned long) ka->sa.sa_handler; + + asm volatile("movl %0,%%ds" :: "r" (__USER32_DS)); + asm volatile("movl %0,%%es" :: "r" (__USER32_DS)); + + regs->cs = __USER32_CS; + regs->ss = __USER32_DS; + + set_fs(USER_DS); + if (regs->eflags & TF_MASK) { + if (current->ptrace & PT_PTRACED) { + ptrace_notify(SIGTRAP); + } else { + regs->eflags &= ~TF_MASK; + } + } + +#if DEBUG_SIG + printk("SIG deliver (%s:%d): sp=%p pc=%p ra=%p\n", + current->comm, current->pid, frame, regs->rip, frame->pretcode); +#endif + + return; + +give_sigsegv: + force_sigsegv(sig, current); +} + +void ia32_setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, + compat_sigset_t *set, struct pt_regs * regs) +{ + struct rt_sigframe __user *frame; + int err = 0; + + frame = get_sigframe(ka, regs, sizeof(*frame)); + + if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) + goto give_sigsegv; + + { + struct exec_domain *ed = current_thread_info()->exec_domain; + err |= __put_user((ed + && ed->signal_invmap + && sig < 32 + ? ed->signal_invmap[sig] + : sig), + &frame->sig); + } + err |= __put_user(ptr_to_compat(&frame->info), &frame->pinfo); + err |= __put_user(ptr_to_compat(&frame->uc), &frame->puc); + err |= copy_siginfo_to_user32(&frame->info, info); + if (err) + goto give_sigsegv; + + /* Create the ucontext. */ + err |= __put_user(0, &frame->uc.uc_flags); + err |= __put_user(0, &frame->uc.uc_link); + err |= __put_user(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp); + err |= __put_user(sas_ss_flags(regs->rsp), + &frame->uc.uc_stack.ss_flags); + err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size); + err |= ia32_setup_sigcontext(&frame->uc.uc_mcontext, &frame->fpstate, + regs, set->sig[0]); + err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); + if (err) + goto give_sigsegv; + + + { + void __user *restorer = VSYSCALL32_RTSIGRETURN; + if (ka->sa.sa_flags & SA_RESTORER) + restorer = ka->sa.sa_restorer; + err |= __put_user(ptr_to_compat(restorer), &frame->pretcode); + } + + /* This is movl $,%eax ; int $0x80 */ + /* Not actually used anymore, but left because some gdb versions + need it. */ + { + /* __copy_to_user optimizes that into a single 8 byte store */ + static const struct { + u8 movl; + u32 val; + u16 int80; + u16 pad; + u8 pad2; + } __attribute__((packed)) code = { + 0xb8, + __NR_ia32_rt_sigreturn, + 0x80cd, + 0, + }; + err |= __copy_to_user(frame->retcode, &code, 8); + } + if (err) + goto give_sigsegv; + + /* Set up registers for signal handler */ + regs->rsp = (unsigned long) frame; + regs->rip = (unsigned long) ka->sa.sa_handler; + + asm volatile("movl %0,%%ds" :: "r" (__USER32_DS)); + asm volatile("movl %0,%%es" :: "r" (__USER32_DS)); + + regs->cs = __USER32_CS; + regs->ss = __USER32_DS; + + set_fs(USER_DS); + if (regs->eflags & TF_MASK) { + if (current->ptrace & PT_PTRACED) { + ptrace_notify(SIGTRAP); + } else { + regs->eflags &= ~TF_MASK; + } + } + +#if DEBUG_SIG + printk("SIG deliver (%s:%d): sp=%p pc=%p ra=%p\n", + current->comm, current->pid, frame, regs->rip, frame->pretcode); +#endif + + return; + +give_sigsegv: + force_sigsegv(sig, current); +} + |