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qemu/linux-user/i386/signal.c
Philippe Mathieu-Daudé eed4e3d4c6 linux-user/i386: Use explicit little-endian LD/ST API 
The x86 architecture uses little endianness. Directly use
the little-endian LD/ST API.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20241003234211.53644-4-philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2024-10-15 12:13:59 -03:00

868 lines
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/*
* Emulation of Linux signals
*
* Copyright (c) 2003 Fabrice Bellard
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see <http://www.gnu.org/licenses/>.
*/
#include "qemu/osdep.h"
#include "qemu.h"
#include "user-internals.h"
#include "signal-common.h"
#include "linux-user/trace.h"
#include "user/tswap-target.h"
/* from the Linux kernel - /arch/x86/include/uapi/asm/sigcontext.h */
#define TARGET_FP_XSTATE_MAGIC1 0x46505853U /* FPXS */
#define TARGET_FP_XSTATE_MAGIC2 0x46505845U /* FPXE */
#define TARGET_FP_XSTATE_MAGIC2_SIZE 4
struct target_fpreg {
uint16_t significand[4];
uint16_t exponent;
};
/* Legacy x87 fpu state format for FSAVE/FRESTOR. */
struct target_fregs_state {
uint32_t cwd;
uint32_t swd;
uint32_t twd;
uint32_t fip;
uint32_t fcs;
uint32_t foo;
uint32_t fos;
struct target_fpreg st[8];
/* Software status information [not touched by FSAVE]. */
uint16_t status;
uint16_t magic; /* 0xffff: FPU data only, 0x0000: FXSR FPU data */
};
QEMU_BUILD_BUG_ON(sizeof(struct target_fregs_state) != 32 + 80);
struct target_fpx_sw_bytes {
uint32_t magic1;
uint32_t extended_size;
uint64_t xfeatures;
uint32_t xstate_size;
uint32_t reserved[7];
};
QEMU_BUILD_BUG_ON(sizeof(struct target_fpx_sw_bytes) != 12*4);
struct target_fpstate_32 {
struct target_fregs_state fpstate;
X86LegacyXSaveArea fxstate;
};
struct target_sigcontext_32 {
uint16_t gs, __gsh;
uint16_t fs, __fsh;
uint16_t es, __esh;
uint16_t ds, __dsh;
uint32_t edi;
uint32_t esi;
uint32_t ebp;
uint32_t esp;
uint32_t ebx;
uint32_t edx;
uint32_t ecx;
uint32_t eax;
uint32_t trapno;
uint32_t err;
uint32_t eip;
uint16_t cs, __csh;
uint32_t eflags;
uint32_t esp_at_signal;
uint16_t ss, __ssh;
uint32_t fpstate; /* pointer */
uint32_t oldmask;
uint32_t cr2;
};
struct target_sigcontext_64 {
uint64_t r8;
uint64_t r9;
uint64_t r10;
uint64_t r11;
uint64_t r12;
uint64_t r13;
uint64_t r14;
uint64_t r15;
uint64_t rdi;
uint64_t rsi;
uint64_t rbp;
uint64_t rbx;
uint64_t rdx;
uint64_t rax;
uint64_t rcx;
uint64_t rsp;
uint64_t rip;
uint64_t eflags;
uint16_t cs;
uint16_t gs;
uint16_t fs;
uint16_t ss;
uint64_t err;
uint64_t trapno;
uint64_t oldmask;
uint64_t cr2;
uint64_t fpstate; /* pointer */
uint64_t padding[8];
};
#ifndef TARGET_X86_64
# define target_sigcontext target_sigcontext_32
#else
# define target_sigcontext target_sigcontext_64
#endif
/* see Linux/include/uapi/asm-generic/ucontext.h */
struct target_ucontext {
abi_ulong tuc_flags;
abi_ulong tuc_link;
target_stack_t tuc_stack;
struct target_sigcontext tuc_mcontext;
target_sigset_t tuc_sigmask; /* mask last for extensibility */
};
#ifndef TARGET_X86_64
struct sigframe {
abi_ulong pretcode;
int sig;
struct target_sigcontext sc;
/*
* The actual fpstate is placed after retcode[] below, to make room
* for the variable-sized xsave data. The older unused fpstate has
* to be kept to avoid changing the offset of extramask[], which
* is part of the ABI.
*/
struct target_fpstate_32 fpstate_unused;
abi_ulong extramask[TARGET_NSIG_WORDS-1];
char retcode[8];
/* fp state follows here */
};
struct rt_sigframe {
abi_ulong pretcode;
int sig;
abi_ulong pinfo;
abi_ulong puc;
struct target_siginfo info;
struct target_ucontext uc;
char retcode[8];
/* fp state follows here */
};
/*
* Verify that vdso-asmoffset.h constants match.
*/
#include "i386/vdso-asmoffset.h"
QEMU_BUILD_BUG_ON(offsetof(struct sigframe, sc.eip)
!= SIGFRAME_SIGCONTEXT_eip);
QEMU_BUILD_BUG_ON(offsetof(struct rt_sigframe, uc.tuc_mcontext.eip)
!= RT_SIGFRAME_SIGCONTEXT_eip);
#else
struct rt_sigframe {
abi_ulong pretcode;
struct target_ucontext uc;
struct target_siginfo info;
/* fp state follows here */
};
#endif
typedef enum {
#ifndef TARGET_X86_64
FPSTATE_FSAVE,
#endif
FPSTATE_FXSAVE,
FPSTATE_XSAVE
} FPStateKind;
static FPStateKind get_fpstate_kind(CPUX86State *env)
{
if (env->features[FEAT_1_ECX] & CPUID_EXT_XSAVE) {
return FPSTATE_XSAVE;
}
#ifdef TARGET_X86_64
return FPSTATE_FXSAVE;
#else
if (env->features[FEAT_1_EDX] & CPUID_FXSR) {
return FPSTATE_FXSAVE;
}
return FPSTATE_FSAVE;
#endif
}
static unsigned get_fpstate_size(CPUX86State *env, FPStateKind fpkind)
{
/*
* Kernel:
* fpu__alloc_mathframe
* xstate_sigframe_size(current->thread.fpu.fpstate);
* size = fpstate->user_size
* use_xsave() ? size + FP_XSTATE_MAGIC2_SIZE : size
* where fpstate->user_size is computed at init in
* fpu__init_system_xstate_size_legacy and
* fpu__init_system_xstate.
*
* Here we have no place to pre-compute, so inline it all.
*/
switch (fpkind) {
case FPSTATE_XSAVE:
return (xsave_area_size(env->xcr0, false)
+ TARGET_FP_XSTATE_MAGIC2_SIZE);
case FPSTATE_FXSAVE:
return sizeof(X86LegacyXSaveArea);
#ifndef TARGET_X86_64
case FPSTATE_FSAVE:
return sizeof(struct target_fregs_state);
#endif
}
g_assert_not_reached();
}
static abi_ptr get_sigframe(struct target_sigaction *ka, CPUX86State *env,
unsigned frame_size, FPStateKind fpkind,
abi_ptr *fpstate, abi_ptr *fxstate, abi_ptr *fpend)
{
abi_ptr sp;
unsigned math_size;
/* Default to using normal stack */
sp = get_sp_from_cpustate(env);
#ifdef TARGET_X86_64
sp -= 128; /* this is the redzone */
#endif
/* This is the X/Open sanctioned signal stack switching. */
if (ka->sa_flags & TARGET_SA_ONSTACK) {
sp = target_sigsp(sp, ka);
} else {
#ifndef TARGET_X86_64
/* This is the legacy signal stack switching. */
if ((env->segs[R_SS].selector & 0xffff) != __USER_DS
&& !(ka->sa_flags & TARGET_SA_RESTORER)
&& ka->sa_restorer) {
sp = ka->sa_restorer;
}
#endif
}
math_size = get_fpstate_size(env, fpkind);
sp = ROUND_DOWN(sp - math_size, 64);
*fpend = sp + math_size;
*fxstate = sp;
#ifndef TARGET_X86_64
if (fpkind != FPSTATE_FSAVE) {
sp -= sizeof(struct target_fregs_state);
}
#endif
*fpstate = sp;
sp -= frame_size;
/*
* Align the stack pointer according to the ABI, i.e. so that on
* function entry ((sp + sizeof(return_addr)) & 15) == 0.
*/
sp += sizeof(target_ulong);
sp = ROUND_DOWN(sp, 16);
sp -= sizeof(target_ulong);
return sp;
}
/*
* Set up a signal frame.
*/
static void fxsave_sigcontext(CPUX86State *env, X86LegacyXSaveArea *fxstate)
{
struct target_fpx_sw_bytes *sw = (void *)&fxstate->sw_reserved;
cpu_x86_fxsave(env, fxstate, sizeof(*fxstate));
__put_user(0, &sw->magic1);
}
static void xsave_sigcontext(CPUX86State *env,
X86LegacyXSaveArea *fxstate,
abi_ptr fpstate_addr,
abi_ptr xstate_addr,
abi_ptr fpend_addr)
{
struct target_fpx_sw_bytes *sw = (void *)&fxstate->sw_reserved;
/*
* extended_size is the offset from fpstate_addr to right after
* the end of the extended save states. On 32-bit that includes
* the legacy FSAVE area.
*/
uint32_t extended_size = fpend_addr - fpstate_addr;
/* Recover xstate_size by removing magic2. */
uint32_t xstate_size = (fpend_addr - xstate_addr
- TARGET_FP_XSTATE_MAGIC2_SIZE);
/* magic2 goes just after xstate. */
uint32_t *magic2 = (void *)fxstate + xstate_size;
/* xstate_addr must be 64 byte aligned for xsave */
assert(!(xstate_addr & 0x3f));
/* Zero the header, XSAVE *adds* features to an existing save state. */
memset(fxstate + 1, 0, sizeof(X86XSaveHeader));
cpu_x86_xsave(env, fxstate, fpend_addr - xstate_addr, env->xcr0);
__put_user(TARGET_FP_XSTATE_MAGIC1, &sw->magic1);
__put_user(extended_size, &sw->extended_size);
__put_user(env->xcr0, &sw->xfeatures);
__put_user(xstate_size, &sw->xstate_size);
__put_user(TARGET_FP_XSTATE_MAGIC2, magic2);
}
static void setup_sigcontext(CPUX86State *env,
struct target_sigcontext *sc,
abi_ulong mask, FPStateKind fpkind,
struct target_fregs_state *fpstate,
abi_ptr fpstate_addr,
X86LegacyXSaveArea *fxstate,
abi_ptr fxstate_addr,
abi_ptr fpend_addr)
{
CPUState *cs = env_cpu(env);
#ifndef TARGET_X86_64
uint16_t magic;
/* already locked in setup_frame() */
__put_user(env->segs[R_GS].selector, (uint32_t *)&sc->gs);
__put_user(env->segs[R_FS].selector, (uint32_t *)&sc->fs);
__put_user(env->segs[R_ES].selector, (uint32_t *)&sc->es);
__put_user(env->segs[R_DS].selector, (uint32_t *)&sc->ds);
__put_user(env->regs[R_EDI], &sc->edi);
__put_user(env->regs[R_ESI], &sc->esi);
__put_user(env->regs[R_EBP], &sc->ebp);
__put_user(env->regs[R_ESP], &sc->esp);
__put_user(env->regs[R_EBX], &sc->ebx);
__put_user(env->regs[R_EDX], &sc->edx);
__put_user(env->regs[R_ECX], &sc->ecx);
__put_user(env->regs[R_EAX], &sc->eax);
__put_user(cs->exception_index, &sc->trapno);
__put_user(env->error_code, &sc->err);
__put_user(env->eip, &sc->eip);
__put_user(env->segs[R_CS].selector, (uint32_t *)&sc->cs);
__put_user(env->eflags, &sc->eflags);
__put_user(env->regs[R_ESP], &sc->esp_at_signal);
__put_user(env->segs[R_SS].selector, (uint32_t *)&sc->ss);
cpu_x86_fsave(env, fpstate, sizeof(*fpstate));
fpstate->status = fpstate->swd;
magic = (fpkind == FPSTATE_FSAVE ? 0 : 0xffff);
__put_user(magic, &fpstate->magic);
#else
__put_user(env->regs[R_EDI], &sc->rdi);
__put_user(env->regs[R_ESI], &sc->rsi);
__put_user(env->regs[R_EBP], &sc->rbp);
__put_user(env->regs[R_ESP], &sc->rsp);
__put_user(env->regs[R_EBX], &sc->rbx);
__put_user(env->regs[R_EDX], &sc->rdx);
__put_user(env->regs[R_ECX], &sc->rcx);
__put_user(env->regs[R_EAX], &sc->rax);
__put_user(env->regs[8], &sc->r8);
__put_user(env->regs[9], &sc->r9);
__put_user(env->regs[10], &sc->r10);
__put_user(env->regs[11], &sc->r11);
__put_user(env->regs[12], &sc->r12);
__put_user(env->regs[13], &sc->r13);
__put_user(env->regs[14], &sc->r14);
__put_user(env->regs[15], &sc->r15);
__put_user(cs->exception_index, &sc->trapno);
__put_user(env->error_code, &sc->err);
__put_user(env->eip, &sc->rip);
__put_user(env->eflags, &sc->eflags);
__put_user(env->segs[R_CS].selector, &sc->cs);
__put_user((uint16_t)0, &sc->gs);
__put_user((uint16_t)0, &sc->fs);
__put_user(env->segs[R_SS].selector, &sc->ss);
#endif
switch (fpkind) {
case FPSTATE_XSAVE:
xsave_sigcontext(env, fxstate, fpstate_addr, fxstate_addr, fpend_addr);
break;
case FPSTATE_FXSAVE:
fxsave_sigcontext(env, fxstate);
break;
default:
break;
}
__put_user(fpstate_addr, &sc->fpstate);
/* non-iBCS2 extensions.. */
__put_user(mask, &sc->oldmask);
__put_user(env->cr[2], &sc->cr2);
}
#ifndef TARGET_X86_64
static void install_sigtramp(void *tramp)
{
/* This is popl %eax ; movl $syscall,%eax ; int $0x80 */
__put_user(0xb858, (uint16_t *)(tramp + 0));
__put_user(TARGET_NR_sigreturn, (int32_t *)(tramp + 2));
__put_user(0x80cd, (uint16_t *)(tramp + 6));
}
static void install_rt_sigtramp(void *tramp)
{
/* This is movl $syscall,%eax ; int $0x80 */
__put_user(0xb8, (uint8_t *)(tramp + 0));
__put_user(TARGET_NR_rt_sigreturn, (int32_t *)(tramp + 1));
__put_user(0x80cd, (uint16_t *)(tramp + 5));
}
/* compare linux/arch/i386/kernel/signal.c:setup_frame() */
void setup_frame(int sig, struct target_sigaction *ka,
target_sigset_t *set, CPUX86State *env)
{
abi_ptr frame_addr, fpstate_addr, fxstate_addr, fpend_addr;
struct sigframe *frame;
struct target_fregs_state *fpstate;
X86LegacyXSaveArea *fxstate;
unsigned total_size;
FPStateKind fpkind;
fpkind = get_fpstate_kind(env);
frame_addr = get_sigframe(ka, env, sizeof(struct sigframe), fpkind,
&fpstate_addr, &fxstate_addr, &fpend_addr);
trace_user_setup_frame(env, frame_addr);
total_size = fpend_addr - frame_addr;
frame = lock_user(VERIFY_WRITE, frame_addr, total_size, 0);
if (!frame) {
force_sigsegv(sig);
return;
}
fxstate = (void *)frame + (fxstate_addr - frame_addr);
#ifdef TARGET_X86_64
fpstate = NULL;
#else
fpstate = (void *)frame + (fpstate_addr - frame_addr);
#endif
setup_sigcontext(env, &frame->sc, set->sig[0], fpkind,
fpstate, fpstate_addr, fxstate, fxstate_addr, fpend_addr);
for (int i = 1; i < TARGET_NSIG_WORDS; i++) {
__put_user(set->sig[i], &frame->extramask[i - 1]);
}
/* Set up to return from userspace. If provided, use a stub
already in userspace. */
if (ka->sa_flags & TARGET_SA_RESTORER) {
__put_user(ka->sa_restorer, &frame->pretcode);
} else {
/* This is no longer used, but is retained for ABI compatibility. */
install_sigtramp(frame->retcode);
__put_user(default_sigreturn, &frame->pretcode);
}
unlock_user(frame, frame_addr, total_size);
/* Set up registers for signal handler */
env->regs[R_ESP] = frame_addr;
env->eip = ka->_sa_handler;
/* Store argument for both -mregparm=3 and standard. */
env->regs[R_EAX] = sig;
__put_user(sig, &frame->sig);
/* The kernel clears EDX and ECX even though there is only one arg. */
env->regs[R_EDX] = 0;
env->regs[R_ECX] = 0;
cpu_x86_load_seg(env, R_DS, __USER_DS);
cpu_x86_load_seg(env, R_ES, __USER_DS);
cpu_x86_load_seg(env, R_SS, __USER_DS);
cpu_x86_load_seg(env, R_CS, __USER_CS);
env->eflags &= ~TF_MASK;
}
#endif
/* compare linux/arch/x86/kernel/signal.c:setup_rt_frame() */
void setup_rt_frame(int sig, struct target_sigaction *ka,
target_siginfo_t *info,
target_sigset_t *set, CPUX86State *env)
{
abi_ptr frame_addr, fpstate_addr, fxstate_addr, fpend_addr;
struct rt_sigframe *frame;
X86LegacyXSaveArea *fxstate;
struct target_fregs_state *fpstate;
unsigned total_size;
FPStateKind fpkind;
fpkind = get_fpstate_kind(env);
frame_addr = get_sigframe(ka, env, sizeof(struct rt_sigframe), fpkind,
&fpstate_addr, &fxstate_addr, &fpend_addr);
trace_user_setup_rt_frame(env, frame_addr);
total_size = fpend_addr - frame_addr;
frame = lock_user(VERIFY_WRITE, frame_addr, total_size, 0);
if (!frame) {
goto give_sigsegv;
}
if (ka->sa_flags & TARGET_SA_SIGINFO) {
frame->info = *info;
}
/* Create the ucontext. */
__put_user(fpkind == FPSTATE_XSAVE, &frame->uc.tuc_flags);
__put_user(0, &frame->uc.tuc_link);
target_save_altstack(&frame->uc.tuc_stack, env);
fxstate = (void *)frame + (fxstate_addr - frame_addr);
#ifdef TARGET_X86_64
fpstate = NULL;
#else
fpstate = (void *)frame + (fpstate_addr - frame_addr);
#endif
setup_sigcontext(env, &frame->uc.tuc_mcontext, set->sig[0], fpkind,
fpstate, fpstate_addr, fxstate, fxstate_addr, fpend_addr);
for (int i = 0; i < TARGET_NSIG_WORDS; i++) {
__put_user(set->sig[i], &frame->uc.tuc_sigmask.sig[i]);
}
/*
* Set up to return from userspace. If provided, use a stub
* already in userspace.
*/
if (ka->sa_flags & TARGET_SA_RESTORER) {
__put_user(ka->sa_restorer, &frame->pretcode);
} else {
#ifdef TARGET_X86_64
/* For x86_64, SA_RESTORER is required ABI. */
goto give_sigsegv;
#else
/* This is no longer used, but is retained for ABI compatibility. */
install_rt_sigtramp(frame->retcode);
__put_user(default_rt_sigreturn, &frame->pretcode);
#endif
}
/* Set up registers for signal handler */
env->regs[R_ESP] = frame_addr;
env->eip = ka->_sa_handler;
#ifndef TARGET_X86_64
/* Store arguments for both -mregparm=3 and standard. */
env->regs[R_EAX] = sig;
__put_user(sig, &frame->sig);
env->regs[R_EDX] = frame_addr + offsetof(struct rt_sigframe, info);
__put_user(env->regs[R_EDX], &frame->pinfo);
env->regs[R_ECX] = frame_addr + offsetof(struct rt_sigframe, uc);
__put_user(env->regs[R_ECX], &frame->puc);
#else
env->regs[R_EAX] = 0;
env->regs[R_EDI] = sig;
env->regs[R_ESI] = frame_addr + offsetof(struct rt_sigframe, info);
env->regs[R_EDX] = frame_addr + offsetof(struct rt_sigframe, uc);
#endif
unlock_user(frame, frame_addr, total_size);
cpu_x86_load_seg(env, R_DS, __USER_DS);
cpu_x86_load_seg(env, R_ES, __USER_DS);
cpu_x86_load_seg(env, R_CS, __USER_CS);
cpu_x86_load_seg(env, R_SS, __USER_DS);
env->eflags &= ~TF_MASK;
return;
give_sigsegv:
force_sigsegv(sig);
}
/*
* Restore a signal frame.
*/
static bool xrstor_sigcontext(CPUX86State *env, FPStateKind fpkind,
X86LegacyXSaveArea *fxstate,
abi_ptr fxstate_addr)
{
struct target_fpx_sw_bytes *sw = (void *)&fxstate->sw_reserved;
uint32_t magic1, magic2;
uint32_t extended_size, xstate_size, min_size, max_size;
uint64_t xfeatures;
void *xstate;
bool ok;
switch (fpkind) {
case FPSTATE_XSAVE:
magic1 = tswap32(sw->magic1);
extended_size = tswap32(sw->extended_size);
xstate_size = tswap32(sw->xstate_size);
min_size = sizeof(X86LegacyXSaveArea) + sizeof(X86XSaveHeader);
max_size = xsave_area_size(env->xcr0, false);
/* Check for the first magic field and other error scenarios. */
if (magic1 != TARGET_FP_XSTATE_MAGIC1 ||
xstate_size < min_size ||
xstate_size > max_size ||
xstate_size > extended_size) {
break;
}
/*
* Restore the features indicated in the frame, masked by
* those currently enabled. Re-check the frame size.
* ??? It is not clear where the kernel does this, but it
* is not in check_xstate_in_sigframe, and so (probably)
* does not fall back to fxrstor.
*/
xfeatures = tswap64(sw->xfeatures) & env->xcr0;
min_size = xsave_area_size(xfeatures, false);
if (xstate_size < min_size) {
return false;
}
/* Re-lock the entire xstate area, with the extensions and magic. */
xstate = lock_user(VERIFY_READ, fxstate_addr,
xstate_size + TARGET_FP_XSTATE_MAGIC2_SIZE, 1);
if (!xstate) {
return false;
}
/*
* Check for the presence of second magic word at the end of memory
* layout. This detects the case where the user just copied the legacy
* fpstate layout with out copying the extended state information
* in the memory layout.
*/
magic2 = tswap32(*(uint32_t *)(xstate + xstate_size));
if (magic2 != TARGET_FP_XSTATE_MAGIC2) {
unlock_user(xstate, fxstate_addr, 0);
break;
}
ok = cpu_x86_xrstor(env, xstate, xstate_size, xfeatures);
unlock_user(xstate, fxstate_addr, 0);
return ok;
default:
break;
}
cpu_x86_fxrstor(env, fxstate, sizeof(*fxstate));
return true;
}
#ifndef TARGET_X86_64
static bool frstor_sigcontext(CPUX86State *env, FPStateKind fpkind,
struct target_fregs_state *fpstate,
abi_ptr fpstate_addr,
X86LegacyXSaveArea *fxstate,
abi_ptr fxstate_addr)
{
switch (fpkind) {
case FPSTATE_XSAVE:
if (!xrstor_sigcontext(env, fpkind, fxstate, fxstate_addr)) {
return false;
}
break;
case FPSTATE_FXSAVE:
cpu_x86_fxrstor(env, fxstate, sizeof(*fxstate));
break;
case FPSTATE_FSAVE:
break;
default:
g_assert_not_reached();
}
/*
* Copy the legacy state because the FP portion of the FX frame has
* to be ignored for histerical raisins. The kernel folds the two
* states together and then performs a single load; here we perform
* the merge within ENV by loading XSTATE/FXSTATE first, then
* overriding with the FSTATE afterward.
*/
cpu_x86_frstor(env, fpstate, sizeof(*fpstate));
return true;
}
#endif
static bool restore_sigcontext(CPUX86State *env, struct target_sigcontext *sc)
{
abi_ptr fpstate_addr;
unsigned tmpflags, math_size;
FPStateKind fpkind;
void *fpstate;
bool ok;
#ifndef TARGET_X86_64
cpu_x86_load_seg(env, R_GS, tswap16(sc->gs));
cpu_x86_load_seg(env, R_FS, tswap16(sc->fs));
cpu_x86_load_seg(env, R_ES, tswap16(sc->es));
cpu_x86_load_seg(env, R_DS, tswap16(sc->ds));
env->regs[R_EDI] = tswapl(sc->edi);
env->regs[R_ESI] = tswapl(sc->esi);
env->regs[R_EBP] = tswapl(sc->ebp);
env->regs[R_ESP] = tswapl(sc->esp);
env->regs[R_EBX] = tswapl(sc->ebx);
env->regs[R_EDX] = tswapl(sc->edx);
env->regs[R_ECX] = tswapl(sc->ecx);
env->regs[R_EAX] = tswapl(sc->eax);
env->eip = tswapl(sc->eip);
#else
env->regs[8] = tswapl(sc->r8);
env->regs[9] = tswapl(sc->r9);
env->regs[10] = tswapl(sc->r10);
env->regs[11] = tswapl(sc->r11);
env->regs[12] = tswapl(sc->r12);
env->regs[13] = tswapl(sc->r13);
env->regs[14] = tswapl(sc->r14);
env->regs[15] = tswapl(sc->r15);
env->regs[R_EDI] = tswapl(sc->rdi);
env->regs[R_ESI] = tswapl(sc->rsi);
env->regs[R_EBP] = tswapl(sc->rbp);
env->regs[R_EBX] = tswapl(sc->rbx);
env->regs[R_EDX] = tswapl(sc->rdx);
env->regs[R_EAX] = tswapl(sc->rax);
env->regs[R_ECX] = tswapl(sc->rcx);
env->regs[R_ESP] = tswapl(sc->rsp);
env->eip = tswapl(sc->rip);
#endif
cpu_x86_load_seg(env, R_CS, lduw_le_p(&sc->cs) | 3);
cpu_x86_load_seg(env, R_SS, lduw_le_p(&sc->ss) | 3);
tmpflags = tswapl(sc->eflags);
env->eflags = (env->eflags & ~0x40DD5) | (tmpflags & 0x40DD5);
fpstate_addr = tswapl(sc->fpstate);
if (fpstate_addr == 0) {
return true;
}
fpkind = get_fpstate_kind(env);
math_size = get_fpstate_size(env, fpkind);
#ifndef TARGET_X86_64
if (fpkind != FPSTATE_FSAVE) {
math_size += sizeof(struct target_fregs_state);
}
#endif
fpstate = lock_user(VERIFY_READ, fpstate_addr, math_size, 1);
if (!fpstate) {
return false;
}
#ifdef TARGET_X86_64
ok = xrstor_sigcontext(env, fpkind, fpstate, fpstate_addr);
#else
ok = frstor_sigcontext(env, fpkind, fpstate, fpstate_addr,
fpstate + sizeof(struct target_fregs_state),
fpstate_addr + sizeof(struct target_fregs_state));
#endif
unlock_user(fpstate, fpstate_addr, 0);
return ok;
}
/* Note: there is no sigreturn on x86_64, there is only rt_sigreturn */
#ifndef TARGET_X86_64
long do_sigreturn(CPUX86State *env)
{
struct sigframe *frame;
abi_ulong frame_addr = env->regs[R_ESP] - 8;
target_sigset_t target_set;
sigset_t set;
trace_user_do_sigreturn(env, frame_addr);
if (!lock_user_struct(VERIFY_READ, frame, frame_addr, 1)) {
force_sig(TARGET_SIGSEGV);
return -QEMU_ESIGRETURN;
}
/* Set blocked signals. */
__get_user(target_set.sig[0], &frame->sc.oldmask);
for (int i = 1; i < TARGET_NSIG_WORDS; i++) {
__get_user(target_set.sig[i], &frame->extramask[i - 1]);
}
target_to_host_sigset_internal(&set, &target_set);
set_sigmask(&set);
/* Restore registers */
if (!restore_sigcontext(env, &frame->sc)) {
force_sig(TARGET_SIGSEGV);
}
unlock_user_struct(frame, frame_addr, 0);
return -QEMU_ESIGRETURN;
}
#endif
long do_rt_sigreturn(CPUX86State *env)
{
abi_ulong frame_addr;
struct rt_sigframe *frame;
sigset_t set;
frame_addr = env->regs[R_ESP] - sizeof(abi_ulong);
trace_user_do_rt_sigreturn(env, frame_addr);
if (!lock_user_struct(VERIFY_READ, frame, frame_addr, 1))
goto badframe;
target_to_host_sigset(&set, &frame->uc.tuc_sigmask);
set_sigmask(&set);
if (!restore_sigcontext(env, &frame->uc.tuc_mcontext)) {
goto badframe;
}
target_restore_altstack(&frame->uc.tuc_stack, env);
unlock_user_struct(frame, frame_addr, 0);
return -QEMU_ESIGRETURN;
badframe:
unlock_user_struct(frame, frame_addr, 0);
force_sig(TARGET_SIGSEGV);
return -QEMU_ESIGRETURN;
}
#ifndef TARGET_X86_64
void setup_sigtramp(abi_ulong sigtramp_page)
{
uint16_t *tramp = lock_user(VERIFY_WRITE, sigtramp_page, 2 * 8, 0);
assert(tramp != NULL);
default_sigreturn = sigtramp_page;
install_sigtramp(tramp);
default_rt_sigreturn = sigtramp_page + 8;
install_rt_sigtramp(tramp + 8);
unlock_user(tramp, sigtramp_page, 2 * 8);
}
#endif
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