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freebsd-skq/sys/amd64/ia32/ia32_signal.c
Konstantin Belousov 8c6f8f3d5b Add support for the extended FPU states on amd64, both for native 
64bit and 32bit ABIs.  As a side-effect, it enables AVX on capable
CPUs.

In particular:

- Query the CPU support for XSAVE, list of the supported extensions
  and the required size of FPU save area. The hw.use_xsave tunable is
  provided for disabling XSAVE, and hw.xsave_mask may be used to
  select the enabled extensions.

- Remove the FPU save area from PCB and dynamically allocate the
  (run-time sized) user save area on the top of the kernel stack,
  right above the PCB. Reorganize the thread0 PCB initialization to
  postpone it after BSP is queried for save area size.

- The dumppcb, stoppcbs and susppcbs now do not carry the FPU state as
  well. FPU state is only useful for suspend, where it is saved in
  dynamically allocated suspfpusave area.

- Use XSAVE and XRSTOR to save/restore FPU state, if supported and
  enabled.

- Define new mcontext_t flag _MC_HASFPXSTATE, indicating that
  mcontext_t has a valid pointer to out-of-struct extended FPU
  state. Signal handlers are supplied with stack-allocated fpu
  state. The sigreturn(2) and setcontext(2) syscall honour the flag,
  allowing the signal handlers to inspect and manipilate extended
  state in the interrupted context.

- The getcontext(2) never returns extended state, since there is no
  place in the fixed-sized mcontext_t to place variable-sized save
  area. And, since mcontext_t is embedded into ucontext_t, makes it
  impossible to fix in a reasonable way.  Instead of extending
  getcontext(2) syscall, provide a sysarch(2) facility to query
  extended FPU state.

- Add ptrace(2) support for getting and setting extended state; while
  there, implement missed PT_I386_{GET,SET}XMMREGS for 32bit binaries.

- Change fpu_kern KPI to not expose struct fpu_kern_ctx layout to
  consumers, making it opaque. Internally, struct fpu_kern_ctx now
  contains a space for the extended state. Convert in-kernel consumers
  of fpu_kern KPI both on i386 and amd64.

First version of the support for AVX was submitted by Tim Bird
<tim.bird am sony com> on behalf of Sony. This version was written
from scratch.

Tested by:	pho (previous version), Yamagi Burmeister <lists yamagi org>
MFC after:	1 month
2012-01-21 17:45:27 +00:00

1007 lines
29 KiB
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/*-
* Copyright (c) 2003 Peter Wemm
* Copyright (c) 1982, 1987, 1990 The Regents of the University of California.
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* William Jolitz.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_compat.h"
#include <sys/param.h>
#include <sys/exec.h>
#include <sys/fcntl.h>
#include <sys/imgact.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/mutex.h>
#include <sys/mman.h>
#include <sys/namei.h>
#include <sys/pioctl.h>
#include <sys/proc.h>
#include <sys/procfs.h>
#include <sys/resourcevar.h>
#include <sys/systm.h>
#include <sys/signalvar.h>
#include <sys/stat.h>
#include <sys/sx.h>
#include <sys/syscall.h>
#include <sys/syscallsubr.h>
#include <sys/sysctl.h>
#include <sys/sysent.h>
#include <sys/vnode.h>
#include <vm/vm.h>
#include <vm/vm_kern.h>
#include <vm/vm_param.h>
#include <vm/pmap.h>
#include <vm/vm_map.h>
#include <vm/vm_object.h>
#include <vm/vm_extern.h>
#include <compat/freebsd32/freebsd32_signal.h>
#include <compat/freebsd32/freebsd32_util.h>
#include <compat/freebsd32/freebsd32_proto.h>
#include <compat/freebsd32/freebsd32.h>
#include <compat/ia32/ia32_signal.h>
#include <machine/psl.h>
#include <machine/segments.h>
#include <machine/specialreg.h>
#include <machine/frame.h>
#include <machine/md_var.h>
#include <machine/pcb.h>
#include <machine/cpufunc.h>
#ifdef COMPAT_FREEBSD4
static void freebsd4_ia32_sendsig(sig_t, ksiginfo_t *, sigset_t *);
#endif
#define CS_SECURE(cs) (ISPL(cs) == SEL_UPL)
#define EFL_SECURE(ef, oef) ((((ef) ^ (oef)) & ~PSL_USERCHANGE) == 0)
static void
ia32_get_fpcontext(struct thread *td, struct ia32_mcontext *mcp,
char *xfpusave, size_t xfpusave_len)
{
size_t max_len, len;
/*
* XXX Format of 64bit and 32bit FXSAVE areas differs. FXSAVE
* in 32bit mode saves %cs and %ds, while on 64bit it saves
* 64bit instruction and data pointers. Ignore the difference
* for now, it should be irrelevant for most applications.
*/
mcp->mc_ownedfp = fpugetregs(td);
bcopy(get_pcb_user_save_td(td), &mcp->mc_fpstate,
sizeof(mcp->mc_fpstate));
mcp->mc_fpformat = fpuformat();
if (!use_xsave || xfpusave_len == 0)
return;
max_len = cpu_max_ext_state_size - sizeof(struct savefpu);
len = xfpusave_len;
if (len > max_len) {
len = max_len;
bzero(xfpusave + max_len, len - max_len);
}
mcp->mc_flags |= _MC_HASFPXSTATE;
mcp->mc_xfpustate_len = len;
bcopy(get_pcb_user_save_td(td) + 1, xfpusave, len);
}
static int
ia32_set_fpcontext(struct thread *td, const struct ia32_mcontext *mcp,
char *xfpustate, size_t xfpustate_len)
{
int error;
if (mcp->mc_fpformat == _MC_FPFMT_NODEV)
return (0);
else if (mcp->mc_fpformat != _MC_FPFMT_XMM)
return (EINVAL);
else if (mcp->mc_ownedfp == _MC_FPOWNED_NONE) {
/* We don't care what state is left in the FPU or PCB. */
fpstate_drop(td);
error = 0;
} else if (mcp->mc_ownedfp == _MC_FPOWNED_FPU ||
mcp->mc_ownedfp == _MC_FPOWNED_PCB) {
error = fpusetregs(td, (struct savefpu *)&mcp->mc_fpstate,
xfpustate, xfpustate_len);
} else
return (EINVAL);
return (error);
}
/*
* Get machine context.
*/
static int
ia32_get_mcontext(struct thread *td, struct ia32_mcontext *mcp, int flags)
{
struct pcb *pcb;
struct trapframe *tp;
pcb = td->td_pcb;
tp = td->td_frame;
PROC_LOCK(curthread->td_proc);
mcp->mc_onstack = sigonstack(tp->tf_rsp);
PROC_UNLOCK(curthread->td_proc);
/* Entry into kernel always sets TF_HASSEGS */
mcp->mc_gs = tp->tf_gs;
mcp->mc_fs = tp->tf_fs;
mcp->mc_es = tp->tf_es;
mcp->mc_ds = tp->tf_ds;
mcp->mc_edi = tp->tf_rdi;
mcp->mc_esi = tp->tf_rsi;
mcp->mc_ebp = tp->tf_rbp;
mcp->mc_isp = tp->tf_rsp;
mcp->mc_eflags = tp->tf_rflags;
if (flags & GET_MC_CLEAR_RET) {
mcp->mc_eax = 0;
mcp->mc_edx = 0;
mcp->mc_eflags &= ~PSL_C;
} else {
mcp->mc_eax = tp->tf_rax;
mcp->mc_edx = tp->tf_rdx;
}
mcp->mc_ebx = tp->tf_rbx;
mcp->mc_ecx = tp->tf_rcx;
mcp->mc_eip = tp->tf_rip;
mcp->mc_cs = tp->tf_cs;
mcp->mc_esp = tp->tf_rsp;
mcp->mc_ss = tp->tf_ss;
mcp->mc_len = sizeof(*mcp);
mcp->mc_flags = tp->tf_flags;
ia32_get_fpcontext(td, mcp, NULL, 0);
mcp->mc_fsbase = pcb->pcb_fsbase;
mcp->mc_gsbase = pcb->pcb_gsbase;
mcp->mc_xfpustate = 0;
mcp->mc_xfpustate_len = 0;
bzero(mcp->mc_spare2, sizeof(mcp->mc_spare2));
set_pcb_flags(pcb, PCB_FULL_IRET);
return (0);
}
/*
* Set machine context.
*
* However, we don't set any but the user modifiable flags, and we won't
* touch the cs selector.
*/
static int
ia32_set_mcontext(struct thread *td, const struct ia32_mcontext *mcp)
{
struct trapframe *tp;
char *xfpustate;
long rflags;
int ret;
tp = td->td_frame;
if (mcp->mc_len != sizeof(*mcp))
return (EINVAL);
rflags = (mcp->mc_eflags & PSL_USERCHANGE) |
(tp->tf_rflags & ~PSL_USERCHANGE);
if (mcp->mc_flags & _MC_IA32_HASFPXSTATE) {
if (mcp->mc_xfpustate_len > cpu_max_ext_state_size -
sizeof(struct savefpu))
return (EINVAL);
xfpustate = __builtin_alloca(mcp->mc_xfpustate_len);
ret = copyin(PTRIN(mcp->mc_xfpustate), xfpustate,
mcp->mc_xfpustate_len);
if (ret != 0)
return (ret);
} else
xfpustate = NULL;
ret = ia32_set_fpcontext(td, mcp, xfpustate, mcp->mc_xfpustate_len);
if (ret != 0)
return (ret);
tp->tf_gs = mcp->mc_gs;
tp->tf_fs = mcp->mc_fs;
tp->tf_es = mcp->mc_es;
tp->tf_ds = mcp->mc_ds;
tp->tf_flags = TF_HASSEGS;
tp->tf_rdi = mcp->mc_edi;
tp->tf_rsi = mcp->mc_esi;
tp->tf_rbp = mcp->mc_ebp;
tp->tf_rbx = mcp->mc_ebx;
tp->tf_rdx = mcp->mc_edx;
tp->tf_rcx = mcp->mc_ecx;
tp->tf_rax = mcp->mc_eax;
/* trapno, err */
tp->tf_rip = mcp->mc_eip;
tp->tf_rflags = rflags;
tp->tf_rsp = mcp->mc_esp;
tp->tf_ss = mcp->mc_ss;
set_pcb_flags(td->td_pcb, PCB_FULL_IRET);
return (0);
}
/*
* The first two fields of a ucontext_t are the signal mask and
* the machine context. The next field is uc_link; we want to
* avoid destroying the link when copying out contexts.
*/
#define UC_COPY_SIZE offsetof(struct ia32_ucontext, uc_link)
int
freebsd32_getcontext(struct thread *td, struct freebsd32_getcontext_args *uap)
{
struct ia32_ucontext uc;
int ret;
if (uap->ucp == NULL)
ret = EINVAL;
else {
ia32_get_mcontext(td, &uc.uc_mcontext, GET_MC_CLEAR_RET);
PROC_LOCK(td->td_proc);
uc.uc_sigmask = td->td_sigmask;
PROC_UNLOCK(td->td_proc);
bzero(&uc.__spare__, sizeof(uc.__spare__));
ret = copyout(&uc, uap->ucp, UC_COPY_SIZE);
}
return (ret);
}
int
freebsd32_setcontext(struct thread *td, struct freebsd32_setcontext_args *uap)
{
struct ia32_ucontext uc;
int ret;
if (uap->ucp == NULL)
ret = EINVAL;
else {
ret = copyin(uap->ucp, &uc, UC_COPY_SIZE);
if (ret == 0) {
ret = ia32_set_mcontext(td, &uc.uc_mcontext);
if (ret == 0) {
kern_sigprocmask(td, SIG_SETMASK,
&uc.uc_sigmask, NULL, 0);
}
}
}
return (ret == 0 ? EJUSTRETURN : ret);
}
int
freebsd32_swapcontext(struct thread *td, struct freebsd32_swapcontext_args *uap)
{
struct ia32_ucontext uc;
int ret;
if (uap->oucp == NULL || uap->ucp == NULL)
ret = EINVAL;
else {
ia32_get_mcontext(td, &uc.uc_mcontext, GET_MC_CLEAR_RET);
PROC_LOCK(td->td_proc);
uc.uc_sigmask = td->td_sigmask;
PROC_UNLOCK(td->td_proc);
ret = copyout(&uc, uap->oucp, UC_COPY_SIZE);
if (ret == 0) {
ret = copyin(uap->ucp, &uc, UC_COPY_SIZE);
if (ret == 0) {
ret = ia32_set_mcontext(td, &uc.uc_mcontext);
if (ret == 0) {
kern_sigprocmask(td, SIG_SETMASK,
&uc.uc_sigmask, NULL, 0);
}
}
}
}
return (ret == 0 ? EJUSTRETURN : ret);
}
/*
* Send an interrupt to process.
*
* Stack is set up to allow sigcode stored
* at top to call routine, followed by kcall
* to sigreturn routine below. After sigreturn
* resets the signal mask, the stack, and the
* frame pointer, it returns to the user
* specified pc, psl.
*/
#ifdef COMPAT_43
static void
ia32_osendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask)
{
struct ia32_sigframe3 sf, *fp;
struct proc *p;
struct thread *td;
struct sigacts *psp;
struct trapframe *regs;
int sig;
int oonstack;
td = curthread;
p = td->td_proc;
PROC_LOCK_ASSERT(p, MA_OWNED);
sig = ksi->ksi_signo;
psp = p->p_sigacts;
mtx_assert(&psp->ps_mtx, MA_OWNED);
regs = td->td_frame;
oonstack = sigonstack(regs->tf_rsp);
/* Allocate space for the signal handler context. */
if ((td->td_pflags & TDP_ALTSTACK) && !oonstack &&
SIGISMEMBER(psp->ps_sigonstack, sig)) {
fp = (struct ia32_sigframe3 *)(td->td_sigstk.ss_sp +
td->td_sigstk.ss_size - sizeof(sf));
td->td_sigstk.ss_flags |= SS_ONSTACK;
} else
fp = (struct ia32_sigframe3 *)regs->tf_rsp - 1;
/* Translate the signal if appropriate. */
if (p->p_sysent->sv_sigtbl && sig <= p->p_sysent->sv_sigsize)
sig = p->p_sysent->sv_sigtbl[_SIG_IDX(sig)];
/* Build the argument list for the signal handler. */
sf.sf_signum = sig;
sf.sf_scp = (register_t)&fp->sf_siginfo.si_sc;
if (SIGISMEMBER(psp->ps_siginfo, sig)) {
/* Signal handler installed with SA_SIGINFO. */
sf.sf_arg2 = (register_t)&fp->sf_siginfo;
sf.sf_siginfo.si_signo = sig;
sf.sf_siginfo.si_code = ksi->ksi_code;
sf.sf_ah = (uintptr_t)catcher;
} else {
/* Old FreeBSD-style arguments. */
sf.sf_arg2 = ksi->ksi_code;
sf.sf_addr = (register_t)ksi->ksi_addr;
sf.sf_ah = (uintptr_t)catcher;
}
mtx_unlock(&psp->ps_mtx);
PROC_UNLOCK(p);
/* Save most if not all of trap frame. */
sf.sf_siginfo.si_sc.sc_eax = regs->tf_rax;
sf.sf_siginfo.si_sc.sc_ebx = regs->tf_rbx;
sf.sf_siginfo.si_sc.sc_ecx = regs->tf_rcx;
sf.sf_siginfo.si_sc.sc_edx = regs->tf_rdx;
sf.sf_siginfo.si_sc.sc_esi = regs->tf_rsi;
sf.sf_siginfo.si_sc.sc_edi = regs->tf_rdi;
sf.sf_siginfo.si_sc.sc_cs = regs->tf_cs;
sf.sf_siginfo.si_sc.sc_ds = regs->tf_ds;
sf.sf_siginfo.si_sc.sc_ss = regs->tf_ss;
sf.sf_siginfo.si_sc.sc_es = regs->tf_es;
sf.sf_siginfo.si_sc.sc_fs = regs->tf_fs;
sf.sf_siginfo.si_sc.sc_gs = regs->tf_gs;
sf.sf_siginfo.si_sc.sc_isp = regs->tf_rsp;
/* Build the signal context to be used by osigreturn(). */
sf.sf_siginfo.si_sc.sc_onstack = (oonstack) ? 1 : 0;
SIG2OSIG(*mask, sf.sf_siginfo.si_sc.sc_mask);
sf.sf_siginfo.si_sc.sc_esp = regs->tf_rsp;
sf.sf_siginfo.si_sc.sc_ebp = regs->tf_rbp;
sf.sf_siginfo.si_sc.sc_eip = regs->tf_rip;
sf.sf_siginfo.si_sc.sc_eflags = regs->tf_rflags;
sf.sf_siginfo.si_sc.sc_trapno = regs->tf_trapno;
sf.sf_siginfo.si_sc.sc_err = regs->tf_err;
/*
* Copy the sigframe out to the user's stack.
*/
if (copyout(&sf, fp, sizeof(*fp)) != 0) {
#ifdef DEBUG
printf("process %ld has trashed its stack\n", (long)p->p_pid);
#endif
PROC_LOCK(p);
sigexit(td, SIGILL);
}
regs->tf_rsp = (uintptr_t)fp;
regs->tf_rip = p->p_sysent->sv_psstrings - sz_ia32_osigcode;
regs->tf_rflags &= ~(PSL_T | PSL_D);
regs->tf_cs = _ucode32sel;
regs->tf_ds = _udatasel;
regs->tf_es = _udatasel;
regs->tf_fs = _udatasel;
regs->tf_ss = _udatasel;
set_pcb_flags(td->td_pcb, PCB_FULL_IRET);
PROC_LOCK(p);
mtx_lock(&psp->ps_mtx);
}
#endif
#ifdef COMPAT_FREEBSD4
static void
freebsd4_ia32_sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask)
{
struct ia32_sigframe4 sf, *sfp;
struct siginfo32 siginfo;
struct proc *p;
struct thread *td;
struct sigacts *psp;
struct trapframe *regs;
int oonstack;
int sig;
td = curthread;
p = td->td_proc;
siginfo_to_siginfo32(&ksi->ksi_info, &siginfo);
PROC_LOCK_ASSERT(p, MA_OWNED);
sig = siginfo.si_signo;
psp = p->p_sigacts;
mtx_assert(&psp->ps_mtx, MA_OWNED);
regs = td->td_frame;
oonstack = sigonstack(regs->tf_rsp);
/* Save user context. */
bzero(&sf, sizeof(sf));
sf.sf_uc.uc_sigmask = *mask;
sf.sf_uc.uc_stack.ss_sp = (uintptr_t)td->td_sigstk.ss_sp;
sf.sf_uc.uc_stack.ss_size = td->td_sigstk.ss_size;
sf.sf_uc.uc_stack.ss_flags = (td->td_pflags & TDP_ALTSTACK)
? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE;
sf.sf_uc.uc_mcontext.mc_onstack = (oonstack) ? 1 : 0;
sf.sf_uc.uc_mcontext.mc_edi = regs->tf_rdi;
sf.sf_uc.uc_mcontext.mc_esi = regs->tf_rsi;
sf.sf_uc.uc_mcontext.mc_ebp = regs->tf_rbp;
sf.sf_uc.uc_mcontext.mc_isp = regs->tf_rsp; /* XXX */
sf.sf_uc.uc_mcontext.mc_ebx = regs->tf_rbx;
sf.sf_uc.uc_mcontext.mc_edx = regs->tf_rdx;
sf.sf_uc.uc_mcontext.mc_ecx = regs->tf_rcx;
sf.sf_uc.uc_mcontext.mc_eax = regs->tf_rax;
sf.sf_uc.uc_mcontext.mc_trapno = regs->tf_trapno;
sf.sf_uc.uc_mcontext.mc_err = regs->tf_err;
sf.sf_uc.uc_mcontext.mc_eip = regs->tf_rip;
sf.sf_uc.uc_mcontext.mc_cs = regs->tf_cs;
sf.sf_uc.uc_mcontext.mc_eflags = regs->tf_rflags;
sf.sf_uc.uc_mcontext.mc_esp = regs->tf_rsp;
sf.sf_uc.uc_mcontext.mc_ss = regs->tf_ss;
sf.sf_uc.uc_mcontext.mc_ds = regs->tf_ds;
sf.sf_uc.uc_mcontext.mc_es = regs->tf_es;
sf.sf_uc.uc_mcontext.mc_fs = regs->tf_fs;
sf.sf_uc.uc_mcontext.mc_gs = regs->tf_gs;
bzero(sf.sf_uc.uc_mcontext.mc_fpregs,
sizeof(sf.sf_uc.uc_mcontext.mc_fpregs));
bzero(sf.sf_uc.uc_mcontext.__spare__,
sizeof(sf.sf_uc.uc_mcontext.__spare__));
bzero(sf.sf_uc.__spare__, sizeof(sf.sf_uc.__spare__));
/* Allocate space for the signal handler context. */
if ((td->td_pflags & TDP_ALTSTACK) != 0 && !oonstack &&
SIGISMEMBER(psp->ps_sigonstack, sig)) {
sfp = (struct ia32_sigframe4 *)(td->td_sigstk.ss_sp +
td->td_sigstk.ss_size - sizeof(sf));
} else
sfp = (struct ia32_sigframe4 *)regs->tf_rsp - 1;
PROC_UNLOCK(p);
/* Translate the signal if appropriate. */
if (p->p_sysent->sv_sigtbl && sig <= p->p_sysent->sv_sigsize)
sig = p->p_sysent->sv_sigtbl[_SIG_IDX(sig)];
/* Build the argument list for the signal handler. */
sf.sf_signum = sig;
sf.sf_ucontext = (register_t)&sfp->sf_uc;
bzero(&sf.sf_si, sizeof(sf.sf_si));
if (SIGISMEMBER(psp->ps_siginfo, sig)) {
/* Signal handler installed with SA_SIGINFO. */
sf.sf_siginfo = (u_int32_t)(uintptr_t)&sfp->sf_si;
sf.sf_ah = (u_int32_t)(uintptr_t)catcher;
/* Fill in POSIX parts */
sf.sf_si = siginfo;
sf.sf_si.si_signo = sig;
} else {
/* Old FreeBSD-style arguments. */
sf.sf_siginfo = siginfo.si_code;
sf.sf_addr = (u_int32_t)siginfo.si_addr;
sf.sf_ah = (u_int32_t)(uintptr_t)catcher;
}
mtx_unlock(&psp->ps_mtx);
/*
* Copy the sigframe out to the user's stack.
*/
if (copyout(&sf, sfp, sizeof(*sfp)) != 0) {
#ifdef DEBUG
printf("process %ld has trashed its stack\n", (long)p->p_pid);
#endif
PROC_LOCK(p);
sigexit(td, SIGILL);
}
regs->tf_rsp = (uintptr_t)sfp;
regs->tf_rip = p->p_sysent->sv_sigcode_base + sz_ia32_sigcode -
sz_freebsd4_ia32_sigcode;
regs->tf_rflags &= ~(PSL_T | PSL_D);
regs->tf_cs = _ucode32sel;
regs->tf_ss = _udatasel;
regs->tf_ds = _udatasel;
regs->tf_es = _udatasel;
set_pcb_flags(td->td_pcb, PCB_FULL_IRET);
/* leave user %fs and %gs untouched */
PROC_LOCK(p);
mtx_lock(&psp->ps_mtx);
}
#endif /* COMPAT_FREEBSD4 */
void
ia32_sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask)
{
struct ia32_sigframe sf, *sfp;
struct siginfo32 siginfo;
struct proc *p;
struct thread *td;
struct sigacts *psp;
char *sp;
struct trapframe *regs;
char *xfpusave;
size_t xfpusave_len;
int oonstack;
int sig;
siginfo_to_siginfo32(&ksi->ksi_info, &siginfo);
td = curthread;
p = td->td_proc;
PROC_LOCK_ASSERT(p, MA_OWNED);
sig = siginfo.si_signo;
psp = p->p_sigacts;
#ifdef COMPAT_FREEBSD4
if (SIGISMEMBER(psp->ps_freebsd4, sig)) {
freebsd4_ia32_sendsig(catcher, ksi, mask);
return;
}
#endif
#ifdef COMPAT_43
if (SIGISMEMBER(psp->ps_osigset, sig)) {
ia32_osendsig(catcher, ksi, mask);
return;
}
#endif
mtx_assert(&psp->ps_mtx, MA_OWNED);
regs = td->td_frame;
oonstack = sigonstack(regs->tf_rsp);
if (cpu_max_ext_state_size > sizeof(struct savefpu) && use_xsave) {
xfpusave_len = cpu_max_ext_state_size - sizeof(struct savefpu);
xfpusave = __builtin_alloca(xfpusave_len);
} else {
xfpusave_len = 0;
xfpusave = NULL;
}
/* Save user context. */
bzero(&sf, sizeof(sf));
sf.sf_uc.uc_sigmask = *mask;
sf.sf_uc.uc_stack.ss_sp = (uintptr_t)td->td_sigstk.ss_sp;
sf.sf_uc.uc_stack.ss_size = td->td_sigstk.ss_size;
sf.sf_uc.uc_stack.ss_flags = (td->td_pflags & TDP_ALTSTACK)
? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE;
sf.sf_uc.uc_mcontext.mc_onstack = (oonstack) ? 1 : 0;
sf.sf_uc.uc_mcontext.mc_edi = regs->tf_rdi;
sf.sf_uc.uc_mcontext.mc_esi = regs->tf_rsi;
sf.sf_uc.uc_mcontext.mc_ebp = regs->tf_rbp;
sf.sf_uc.uc_mcontext.mc_isp = regs->tf_rsp; /* XXX */
sf.sf_uc.uc_mcontext.mc_ebx = regs->tf_rbx;
sf.sf_uc.uc_mcontext.mc_edx = regs->tf_rdx;
sf.sf_uc.uc_mcontext.mc_ecx = regs->tf_rcx;
sf.sf_uc.uc_mcontext.mc_eax = regs->tf_rax;
sf.sf_uc.uc_mcontext.mc_trapno = regs->tf_trapno;
sf.sf_uc.uc_mcontext.mc_err = regs->tf_err;
sf.sf_uc.uc_mcontext.mc_eip = regs->tf_rip;
sf.sf_uc.uc_mcontext.mc_cs = regs->tf_cs;
sf.sf_uc.uc_mcontext.mc_eflags = regs->tf_rflags;
sf.sf_uc.uc_mcontext.mc_esp = regs->tf_rsp;
sf.sf_uc.uc_mcontext.mc_ss = regs->tf_ss;
sf.sf_uc.uc_mcontext.mc_ds = regs->tf_ds;
sf.sf_uc.uc_mcontext.mc_es = regs->tf_es;
sf.sf_uc.uc_mcontext.mc_fs = regs->tf_fs;
sf.sf_uc.uc_mcontext.mc_gs = regs->tf_gs;
sf.sf_uc.uc_mcontext.mc_len = sizeof(sf.sf_uc.uc_mcontext); /* magic */
ia32_get_fpcontext(td, &sf.sf_uc.uc_mcontext, xfpusave, xfpusave_len);
fpstate_drop(td);
sf.sf_uc.uc_mcontext.mc_fsbase = td->td_pcb->pcb_fsbase;
sf.sf_uc.uc_mcontext.mc_gsbase = td->td_pcb->pcb_gsbase;
bzero(sf.sf_uc.__spare__, sizeof(sf.sf_uc.__spare__));
/* Allocate space for the signal handler context. */
if ((td->td_pflags & TDP_ALTSTACK) != 0 && !oonstack &&
SIGISMEMBER(psp->ps_sigonstack, sig))
sp = td->td_sigstk.ss_sp + td->td_sigstk.ss_size;
else
sp = (char *)regs->tf_rsp;
if (xfpusave != NULL) {
sp -= xfpusave_len;
sp = (char *)((unsigned long)sp & ~0x3Ful);
sf.sf_uc.uc_mcontext.mc_xfpustate = (register_t)sp;
}
sp -= sizeof(sf);
/* Align to 16 bytes. */
sfp = (struct ia32_sigframe *)((uintptr_t)sp & ~0xF);
PROC_UNLOCK(p);
/* Translate the signal if appropriate. */
if (p->p_sysent->sv_sigtbl && sig <= p->p_sysent->sv_sigsize)
sig = p->p_sysent->sv_sigtbl[_SIG_IDX(sig)];
/* Build the argument list for the signal handler. */
sf.sf_signum = sig;
sf.sf_ucontext = (register_t)&sfp->sf_uc;
bzero(&sf.sf_si, sizeof(sf.sf_si));
if (SIGISMEMBER(psp->ps_siginfo, sig)) {
/* Signal handler installed with SA_SIGINFO. */
sf.sf_siginfo = (u_int32_t)(uintptr_t)&sfp->sf_si;
sf.sf_ah = (u_int32_t)(uintptr_t)catcher;
/* Fill in POSIX parts */
sf.sf_si = siginfo;
sf.sf_si.si_signo = sig;
} else {
/* Old FreeBSD-style arguments. */
sf.sf_siginfo = siginfo.si_code;
sf.sf_addr = (u_int32_t)siginfo.si_addr;
sf.sf_ah = (u_int32_t)(uintptr_t)catcher;
}
mtx_unlock(&psp->ps_mtx);
/*
* Copy the sigframe out to the user's stack.
*/
if (copyout(&sf, sfp, sizeof(*sfp)) != 0 ||
(xfpusave != NULL && copyout(xfpusave,
PTRIN(sf.sf_uc.uc_mcontext.mc_xfpustate), xfpusave_len)
!= 0)) {
#ifdef DEBUG
printf("process %ld has trashed its stack\n", (long)p->p_pid);
#endif
PROC_LOCK(p);
sigexit(td, SIGILL);
}
regs->tf_rsp = (uintptr_t)sfp;
regs->tf_rip = p->p_sysent->sv_sigcode_base;
regs->tf_rflags &= ~(PSL_T | PSL_D);
regs->tf_cs = _ucode32sel;
regs->tf_ss = _udatasel;
regs->tf_ds = _udatasel;
regs->tf_es = _udatasel;
set_pcb_flags(td->td_pcb, PCB_FULL_IRET);
/* XXXKIB leave user %fs and %gs untouched */
PROC_LOCK(p);
mtx_lock(&psp->ps_mtx);
}
/*
* System call to cleanup state after a signal
* has been taken. Reset signal mask and
* stack state from context left by sendsig (above).
* Return to previous pc and psl as specified by
* context left by sendsig. Check carefully to
* make sure that the user has not modified the
* state to gain improper privileges.
*/
#ifdef COMPAT_43
int
ofreebsd32_sigreturn(struct thread *td, struct ofreebsd32_sigreturn_args *uap)
{
struct ia32_sigcontext3 sc, *scp;
struct trapframe *regs;
int eflags, error;
ksiginfo_t ksi;
regs = td->td_frame;
error = copyin(uap->sigcntxp, &sc, sizeof(sc));
if (error != 0)
return (error);
scp = &sc;
eflags = scp->sc_eflags;
if (!EFL_SECURE(eflags & ~PSL_RF, regs->tf_rflags & ~PSL_RF)) {
return (EINVAL);
}
if (!CS_SECURE(scp->sc_cs)) {
ksiginfo_init_trap(&ksi);
ksi.ksi_signo = SIGBUS;
ksi.ksi_code = BUS_OBJERR;
ksi.ksi_trapno = T_PROTFLT;
ksi.ksi_addr = (void *)regs->tf_rip;
trapsignal(td, &ksi);
return (EINVAL);
}
regs->tf_ds = scp->sc_ds;
regs->tf_es = scp->sc_es;
regs->tf_fs = scp->sc_fs;
regs->tf_gs = scp->sc_gs;
regs->tf_rax = scp->sc_eax;
regs->tf_rbx = scp->sc_ebx;
regs->tf_rcx = scp->sc_ecx;
regs->tf_rdx = scp->sc_edx;
regs->tf_rsi = scp->sc_esi;
regs->tf_rdi = scp->sc_edi;
regs->tf_cs = scp->sc_cs;
regs->tf_ss = scp->sc_ss;
regs->tf_rbp = scp->sc_ebp;
regs->tf_rsp = scp->sc_esp;
regs->tf_rip = scp->sc_eip;
regs->tf_rflags = eflags;
if (scp->sc_onstack & 1)
td->td_sigstk.ss_flags |= SS_ONSTACK;
else
td->td_sigstk.ss_flags &= ~SS_ONSTACK;
kern_sigprocmask(td, SIG_SETMASK, (sigset_t *)&scp->sc_mask, NULL,
SIGPROCMASK_OLD);
set_pcb_flags(td->td_pcb, PCB_FULL_IRET);
return (EJUSTRETURN);
}
#endif
#ifdef COMPAT_FREEBSD4
/*
* MPSAFE
*/
int
freebsd4_freebsd32_sigreturn(td, uap)
struct thread *td;
struct freebsd4_freebsd32_sigreturn_args /* {
const struct freebsd4_freebsd32_ucontext *sigcntxp;
} */ *uap;
{
struct ia32_ucontext4 uc;
struct trapframe *regs;
struct ia32_ucontext4 *ucp;
int cs, eflags, error;
ksiginfo_t ksi;
error = copyin(uap->sigcntxp, &uc, sizeof(uc));
if (error != 0)
return (error);
ucp = &uc;
regs = td->td_frame;
eflags = ucp->uc_mcontext.mc_eflags;
/*
* Don't allow users to change privileged or reserved flags.
*/
/*
* XXX do allow users to change the privileged flag PSL_RF.
* The cpu sets PSL_RF in tf_eflags for faults. Debuggers
* should sometimes set it there too. tf_eflags is kept in
* the signal context during signal handling and there is no
* other place to remember it, so the PSL_RF bit may be
* corrupted by the signal handler without us knowing.
* Corruption of the PSL_RF bit at worst causes one more or
* one less debugger trap, so allowing it is fairly harmless.
*/
if (!EFL_SECURE(eflags & ~PSL_RF, regs->tf_rflags & ~PSL_RF)) {
uprintf("pid %d (%s): freebsd4_freebsd32_sigreturn eflags = 0x%x\n",
td->td_proc->p_pid, td->td_name, eflags);
return (EINVAL);
}
/*
* Don't allow users to load a valid privileged %cs. Let the
* hardware check for invalid selectors, excess privilege in
* other selectors, invalid %eip's and invalid %esp's.
*/
cs = ucp->uc_mcontext.mc_cs;
if (!CS_SECURE(cs)) {
uprintf("pid %d (%s): freebsd4_sigreturn cs = 0x%x\n",
td->td_proc->p_pid, td->td_name, cs);
ksiginfo_init_trap(&ksi);
ksi.ksi_signo = SIGBUS;
ksi.ksi_code = BUS_OBJERR;
ksi.ksi_trapno = T_PROTFLT;
ksi.ksi_addr = (void *)regs->tf_rip;
trapsignal(td, &ksi);
return (EINVAL);
}
regs->tf_rdi = ucp->uc_mcontext.mc_edi;
regs->tf_rsi = ucp->uc_mcontext.mc_esi;
regs->tf_rbp = ucp->uc_mcontext.mc_ebp;
regs->tf_rbx = ucp->uc_mcontext.mc_ebx;
regs->tf_rdx = ucp->uc_mcontext.mc_edx;
regs->tf_rcx = ucp->uc_mcontext.mc_ecx;
regs->tf_rax = ucp->uc_mcontext.mc_eax;
regs->tf_trapno = ucp->uc_mcontext.mc_trapno;
regs->tf_err = ucp->uc_mcontext.mc_err;
regs->tf_rip = ucp->uc_mcontext.mc_eip;
regs->tf_cs = cs;
regs->tf_rflags = ucp->uc_mcontext.mc_eflags;
regs->tf_rsp = ucp->uc_mcontext.mc_esp;
regs->tf_ss = ucp->uc_mcontext.mc_ss;
regs->tf_ds = ucp->uc_mcontext.mc_ds;
regs->tf_es = ucp->uc_mcontext.mc_es;
regs->tf_fs = ucp->uc_mcontext.mc_fs;
regs->tf_gs = ucp->uc_mcontext.mc_gs;
kern_sigprocmask(td, SIG_SETMASK, &ucp->uc_sigmask, NULL, 0);
set_pcb_flags(td->td_pcb, PCB_FULL_IRET);
return (EJUSTRETURN);
}
#endif /* COMPAT_FREEBSD4 */
/*
* MPSAFE
*/
int
freebsd32_sigreturn(td, uap)
struct thread *td;
struct freebsd32_sigreturn_args /* {
const struct freebsd32_ucontext *sigcntxp;
} */ *uap;
{
struct ia32_ucontext uc;
struct trapframe *regs;
struct ia32_ucontext *ucp;
char *xfpustate;
size_t xfpustate_len;
int cs, eflags, error, ret;
ksiginfo_t ksi;
error = copyin(uap->sigcntxp, &uc, sizeof(uc));
if (error != 0)
return (error);
ucp = &uc;
regs = td->td_frame;
eflags = ucp->uc_mcontext.mc_eflags;
/*
* Don't allow users to change privileged or reserved flags.
*/
/*
* XXX do allow users to change the privileged flag PSL_RF.
* The cpu sets PSL_RF in tf_eflags for faults. Debuggers
* should sometimes set it there too. tf_eflags is kept in
* the signal context during signal handling and there is no
* other place to remember it, so the PSL_RF bit may be
* corrupted by the signal handler without us knowing.
* Corruption of the PSL_RF bit at worst causes one more or
* one less debugger trap, so allowing it is fairly harmless.
*/
if (!EFL_SECURE(eflags & ~PSL_RF, regs->tf_rflags & ~PSL_RF)) {
uprintf("pid %d (%s): freebsd32_sigreturn eflags = 0x%x\n",
td->td_proc->p_pid, td->td_name, eflags);
return (EINVAL);
}
/*
* Don't allow users to load a valid privileged %cs. Let the
* hardware check for invalid selectors, excess privilege in
* other selectors, invalid %eip's and invalid %esp's.
*/
cs = ucp->uc_mcontext.mc_cs;
if (!CS_SECURE(cs)) {
uprintf("pid %d (%s): sigreturn cs = 0x%x\n",
td->td_proc->p_pid, td->td_name, cs);
ksiginfo_init_trap(&ksi);
ksi.ksi_signo = SIGBUS;
ksi.ksi_code = BUS_OBJERR;
ksi.ksi_trapno = T_PROTFLT;
ksi.ksi_addr = (void *)regs->tf_rip;
trapsignal(td, &ksi);
return (EINVAL);
}
if ((ucp->uc_mcontext.mc_flags & _MC_HASFPXSTATE) != 0) {
xfpustate_len = uc.uc_mcontext.mc_xfpustate_len;
if (xfpustate_len > cpu_max_ext_state_size -
sizeof(struct savefpu)) {
uprintf("pid %d (%s): sigreturn xfpusave_len = 0x%zx\n",
td->td_proc->p_pid, td->td_name, xfpustate_len);
return (EINVAL);
}
xfpustate = __builtin_alloca(xfpustate_len);
error = copyin(PTRIN(ucp->uc_mcontext.mc_xfpustate),
xfpustate, xfpustate_len);
if (error != 0) {
uprintf(
"pid %d (%s): sigreturn copying xfpustate failed\n",
td->td_proc->p_pid, td->td_name);
return (error);
}
} else {
xfpustate = NULL;
xfpustate_len = 0;
}
ret = ia32_set_fpcontext(td, &ucp->uc_mcontext, xfpustate,
xfpustate_len);
if (ret != 0) {
uprintf("pid %d (%s): sigreturn set_fpcontext err %d\n",
td->td_proc->p_pid, td->td_name, ret);
return (ret);
}
regs->tf_rdi = ucp->uc_mcontext.mc_edi;
regs->tf_rsi = ucp->uc_mcontext.mc_esi;
regs->tf_rbp = ucp->uc_mcontext.mc_ebp;
regs->tf_rbx = ucp->uc_mcontext.mc_ebx;
regs->tf_rdx = ucp->uc_mcontext.mc_edx;
regs->tf_rcx = ucp->uc_mcontext.mc_ecx;
regs->tf_rax = ucp->uc_mcontext.mc_eax;
regs->tf_trapno = ucp->uc_mcontext.mc_trapno;
regs->tf_err = ucp->uc_mcontext.mc_err;
regs->tf_rip = ucp->uc_mcontext.mc_eip;
regs->tf_cs = cs;
regs->tf_rflags = ucp->uc_mcontext.mc_eflags;
regs->tf_rsp = ucp->uc_mcontext.mc_esp;
regs->tf_ss = ucp->uc_mcontext.mc_ss;
regs->tf_ds = ucp->uc_mcontext.mc_ds;
regs->tf_es = ucp->uc_mcontext.mc_es;
regs->tf_fs = ucp->uc_mcontext.mc_fs;
regs->tf_gs = ucp->uc_mcontext.mc_gs;
regs->tf_flags = TF_HASSEGS;
kern_sigprocmask(td, SIG_SETMASK, &ucp->uc_sigmask, NULL, 0);
set_pcb_flags(td->td_pcb, PCB_FULL_IRET);
return (EJUSTRETURN);
}
/*
* Clear registers on exec
*/
void
ia32_setregs(struct thread *td, struct image_params *imgp, u_long stack)
{
struct trapframe *regs = td->td_frame;
struct pcb *pcb = td->td_pcb;
mtx_lock(&dt_lock);
if (td->td_proc->p_md.md_ldt != NULL)
user_ldt_free(td);
else
mtx_unlock(&dt_lock);
#ifdef COMPAT_43
setup_lcall_gate();
#endif
pcb->pcb_fsbase = 0;
pcb->pcb_gsbase = 0;
pcb->pcb_initial_fpucw = __INITIAL_FPUCW_I386__;
bzero((char *)regs, sizeof(struct trapframe));
regs->tf_rip = imgp->entry_addr;
regs->tf_rsp = stack;
regs->tf_rflags = PSL_USER | (regs->tf_rflags & PSL_T);
regs->tf_ss = _udatasel;
regs->tf_cs = _ucode32sel;
regs->tf_rbx = imgp->ps_strings;
regs->tf_ds = _udatasel;
regs->tf_es = _udatasel;
regs->tf_fs = _ufssel;
regs->tf_gs = _ugssel;
regs->tf_flags = TF_HASSEGS;
fpstate_drop(td);
/* Return via doreti so that we can change to a different %cs */
set_pcb_flags(pcb, PCB_32BIT | PCB_FULL_IRET);
clear_pcb_flags(pcb, PCB_GS32BIT);
td->td_retval[1] = 0;
}
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