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gems-kernel/source/THIRDPARTY/xnu/bsd/dev/i386/unix_signal.c

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add darwin/xnu functionality
2024-06-03 16:29:39 +00:00
/*
* Copyright (c) 2000-2006 Apple Computer, Inc. All rights reserved.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
*
* This file contains Original Code and/or Modifications of Original Code
* as defined in and that are subject to the Apple Public Source License
* Version 2.0 (the 'License'). You may not use this file except in
* compliance with the License. The rights granted to you under the License
* may not be used to create, or enable the creation or redistribution of,
* unlawful or unlicensed copies of an Apple operating system, or to
* circumvent, violate, or enable the circumvention or violation of, any
* terms of an Apple operating system software license agreement.
*
* Please obtain a copy of the License at
* http://www.opensource.apple.com/apsl/ and read it before using this file.
*
* The Original Code and all software distributed under the License are
* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
* Please see the License for the specific language governing rights and
* limitations under the License.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
*/
/*
* Copyright (c) 1992 NeXT, Inc.
*
* HISTORY
* 13 May 1992 ? at NeXT
* Created.
*/
#include <mach/mach_types.h>
#include <mach/exception.h>
#include <kern/thread.h>
#include <kern/ast.h>
#include <sys/systm.h>
#include <sys/param.h>
#include <sys/proc_internal.h>
#include <sys/user.h>
#include <sys/sysproto.h>
#include <sys/sysent.h>
#include <sys/ucontext.h>
#include <sys/wait.h>
#include <sys/ux_exception.h>
#include <mach/thread_act.h> /* for thread_abort_safely */
#include <mach/thread_status.h>
#include <i386/eflags.h>
#include <i386/psl.h>
#include <i386/machine_routines.h>
#include <i386/seg.h>
#include <i386/fpu.h>
#include <machine/pal_routines.h>
#include <sys/kdebug.h>
#include <sys/sdt.h>
#include <sys/random.h>
/* Forward: */
extern kern_return_t thread_getstatus(thread_t act, int flavor,
thread_state_t tstate, mach_msg_type_number_t *count);
extern kern_return_t thread_setstatus(thread_t thread, int flavor,
thread_state_t tstate, mach_msg_type_number_t count);
/* Signal handler flavors supported */
/* These defns should match the Libc implmn */
#define UC_TRAD 1
#define UC_FLAVOR 30
#define UC_SET_ALT_STACK 0x40000000
#define UC_RESET_ALT_STACK 0x80000000
#define C_32_STK_ALIGN 16
#define C_64_STK_ALIGN 16
#define C_64_REDZONE_LEN 128
#define TRUNC_DOWN32(a, c) ((((uint32_t)a)-(c)) & ((uint32_t)(-(c))))
#define TRUNC_DOWN64(a, c) ((((uint64_t)a)-(c)) & ((uint64_t)(-(c))))
/*
* Send an interrupt to process.
*
* Stack is set up to allow sigcode stored
* in u. to call routine, followed by chmk
* to sigreturn routine below. After sigreturn
* resets the signal mask, the stack, the frame
* pointer, and the argument pointer, it returns
* to the user specified pc, psl.
*/
struct sigframe32 {
int retaddr;
user32_addr_t catcher; /* sig_t */
int sigstyle;
int sig;
user32_addr_t sinfo; /* siginfo32_t* */
user32_addr_t uctx; /* struct ucontext32 */
user32_addr_t token;
};
/*
* Declare table of structure flavors and sizes for 64-bit and 32-bit processes
* for the cases of extended states (plain FP, or AVX):
*/
typedef struct {
int flavor; natural_t state_count; size_t mcontext_size;
} xstate_info_t;
static const xstate_info_t thread_state64[] = {
[FP] = { x86_FLOAT_STATE64, x86_FLOAT_STATE64_COUNT, sizeof(struct mcontext64) },
[FP_FULL] = { x86_FLOAT_STATE64, x86_FLOAT_STATE64_COUNT, sizeof(struct mcontext64_full) },
[AVX] = { x86_AVX_STATE64, x86_AVX_STATE64_COUNT, sizeof(struct mcontext_avx64) },
[AVX_FULL] = { x86_AVX_STATE64, x86_AVX_STATE64_COUNT, sizeof(struct mcontext_avx64_full) },
[AVX512] = { x86_AVX512_STATE64, x86_AVX512_STATE64_COUNT, sizeof(struct mcontext_avx512_64) },
[AVX512_FULL] = { x86_AVX512_STATE64, x86_AVX512_STATE64_COUNT, sizeof(struct mcontext_avx512_64_full) }
};
static const xstate_info_t thread_state32[] = {
[FP] = { x86_FLOAT_STATE32, x86_FLOAT_STATE32_COUNT, sizeof(struct mcontext32) },
[AVX] = { x86_AVX_STATE32, x86_AVX_STATE32_COUNT, sizeof(struct mcontext_avx32) },
[AVX512] = { x86_AVX512_STATE32, x86_AVX512_STATE32_COUNT, sizeof(struct mcontext_avx512_32) }
};
/*
* NOTE: Source and target may *NOT* overlap!
* XXX: Unify with bsd/kern/kern_exit.c
*/
static void
siginfo_user_to_user32_x86(user_siginfo_t *in, user32_siginfo_t *out)
{
out->si_signo = in->si_signo;
out->si_errno = in->si_errno;
out->si_code = in->si_code;
out->si_pid = in->si_pid;
out->si_uid = in->si_uid;
out->si_status = in->si_status;
out->si_addr = CAST_DOWN_EXPLICIT(user32_addr_t, in->si_addr);
/* following cast works for sival_int because of padding */
out->si_value.sival_ptr = CAST_DOWN_EXPLICIT(user32_addr_t, in->si_value.sival_ptr);
out->si_band = in->si_band; /* range reduction */
out->__pad[0] = in->pad[0]; /* mcontext.ss.r1 */
}
static void
siginfo_user_to_user64_x86(user_siginfo_t *in, user64_siginfo_t *out)
{
out->si_signo = in->si_signo;
out->si_errno = in->si_errno;
out->si_code = in->si_code;
out->si_pid = in->si_pid;
out->si_uid = in->si_uid;
out->si_status = in->si_status;
out->si_addr = in->si_addr;
out->si_value.sival_ptr = in->si_value.sival_ptr;
out->si_band = in->si_band; /* range reduction */
out->__pad[0] = in->pad[0]; /* mcontext.ss.r1 */
}
void
sendsig(struct proc *p, user_addr_t ua_catcher, int sig, int mask, __unused uint32_t code, sigset_t siginfo)
{
union {
struct mcontext_avx32 mctx_avx32;
struct mcontext_avx64 mctx_avx64;
struct mcontext_avx64_full mctx_avx64_full;
struct mcontext_avx512_32 mctx_avx512_32;
struct mcontext_avx512_64 mctx_avx512_64;
struct mcontext_avx512_64_full mctx_avx512_64_full;
} mctx_store, *mctxp = &mctx_store;
user_addr_t ua_sp;
user_addr_t ua_fp;
user_addr_t ua_cr2;
user_addr_t ua_sip;
user_addr_t ua_uctxp;
user_addr_t ua_mctxp;
user_siginfo_t sinfo64;
struct sigacts *ps = &p->p_sigacts;
int oonstack, flavor;
user_addr_t trampact;
int sigonstack;
void * state, *fpstate;
mach_msg_type_number_t state_count;
thread_t thread;
struct uthread * ut;
int stack_size = 0;
int infostyle = UC_TRAD;
xstate_t sig_xstate;
user_addr_t token_uctx;
kern_return_t kr;
boolean_t reset_ss = TRUE;
thread = current_thread();
ut = get_bsdthread_info(thread);
if (siginfo & sigmask(sig)) {
infostyle = UC_FLAVOR;
}
oonstack = ut->uu_sigstk.ss_flags & SA_ONSTACK;
trampact = SIGTRAMP(p, sig);
sigonstack = (ps->ps_sigonstack & sigmask(sig));
/*
* init siginfo
*/
proc_unlock(p);
bzero((caddr_t)&sinfo64, sizeof(sinfo64));
sinfo64.si_signo = sig;
bzero(mctxp, sizeof(*mctxp));
sig_xstate = current_xstate();
if (ut->uu_pending_sigreturn == 0) {
/* Generate random token value used to validate sigreturn arguments */
read_random(&ut->uu_sigreturn_token, sizeof(ut->uu_sigreturn_token));
}
ut->uu_pending_sigreturn++;
if (proc_is64bit(p)) {
x86_thread_state64_t *tstate64;
struct user_ucontext64 uctx64;
user64_addr_t token;
int task_has_ldt = thread_task_has_ldt(thread);
if (task_has_ldt) {
flavor = x86_THREAD_FULL_STATE64;
state_count = x86_THREAD_FULL_STATE64_COUNT;
fpstate = (void *)&mctxp->mctx_avx64_full.fs;
sig_xstate |= STATE64_FULL;
} else {
flavor = x86_THREAD_STATE64;
state_count = x86_THREAD_STATE64_COUNT;
fpstate = (void *)&mctxp->mctx_avx64.fs;
}
state = (void *)&mctxp->mctx_avx64.ss;
/*
* The state copying is performed with pointers to fields in the state
* struct. This works specifically because the mcontext is layed-out with the
* variable-sized FP-state as the last member. However, with the requirement
* to support passing "full" 64-bit state to the signal handler, that layout has now
* changed (since the "full" state has a larger "ss" member than the non-"full"
* structure. Because of this, and to retain the array-lookup method of determining
* structure sizes, we OR-in STATE64_FULL to sig_xstate to ensure the proper mcontext
* size is passed.
*/
if (thread_getstatus(thread, flavor, (thread_state_t)state, &state_count) != KERN_SUCCESS) {
goto bad;
}
if ((sig_xstate & STATE64_FULL) && mctxp->mctx_avx64.ss.cs != USER64_CS) {
if ((ut->uu_flag & UT_ALTSTACK) && !oonstack &&
(sigonstack)) {
reset_ss = TRUE;
} else {
reset_ss = FALSE;
}
} else {
reset_ss = FALSE;
}
flavor = thread_state64[sig_xstate].flavor;
state_count = thread_state64[sig_xstate].state_count;
if (thread_getstatus(thread, flavor, (thread_state_t)fpstate, &state_count) != KERN_SUCCESS) {
goto bad;
}
flavor = x86_EXCEPTION_STATE64;
state_count = x86_EXCEPTION_STATE64_COUNT;
state = (void *)&mctxp->mctx_avx64.es;
if (thread_getstatus(thread, flavor, (thread_state_t)state, &state_count) != KERN_SUCCESS) {
goto bad;
}
tstate64 = &mctxp->mctx_avx64.ss;
/* figure out where our new stack lives */
if ((ut->uu_flag & UT_ALTSTACK) && !oonstack &&
(sigonstack)) {
ua_sp = ut->uu_sigstk.ss_sp;
stack_size = ut->uu_sigstk.ss_size;
ua_sp += stack_size;
ut->uu_sigstk.ss_flags |= SA_ONSTACK;
} else {
if ((sig_xstate & STATE64_FULL) && tstate64->cs != USER64_CS) {
reset_ss = FALSE;
}
ua_sp = tstate64->rsp;
}
ua_cr2 = mctxp->mctx_avx64.es.faultvaddr;
/* The x86_64 ABI defines a 128-byte red zone. */
ua_sp -= C_64_REDZONE_LEN;
ua_sp -= sizeof(struct user_ucontext64);
ua_uctxp = ua_sp; // someone tramples the first word!
ua_sp -= sizeof(user64_siginfo_t);
ua_sip = ua_sp;
ua_sp -= thread_state64[sig_xstate].mcontext_size;
ua_mctxp = ua_sp;
/*
* Align the frame and stack pointers to 16 bytes for SSE.
* (Note that we use 'ua_fp' as the base of the stack going forward)
*/
ua_fp = TRUNC_DOWN64(ua_sp, C_64_STK_ALIGN);
/*
* But we need to account for the return address so the alignment is
* truly "correct" at _sigtramp
*/
ua_fp -= sizeof(user_addr_t);
/*
* Generate the validation token for sigreturn
*/
token_uctx = ua_uctxp;
kr = machine_thread_siguctx_pointer_convert_to_user(thread, &token_uctx);
assert(kr == KERN_SUCCESS);
token = (user64_addr_t)token_uctx ^ (user64_addr_t)ut->uu_sigreturn_token;
/*
* Build the signal context to be used by sigreturn.
*/
bzero(&uctx64, sizeof(uctx64));
uctx64.uc_onstack = oonstack;
uctx64.uc_sigmask = mask;
uctx64.uc_stack.ss_sp = ua_fp;
uctx64.uc_stack.ss_size = stack_size;
if (oonstack) {
uctx64.uc_stack.ss_flags |= SS_ONSTACK;
}
uctx64.uc_link = 0;
uctx64.uc_mcsize = thread_state64[sig_xstate].mcontext_size;
uctx64.uc_mcontext64 = ua_mctxp;
if (copyout((caddr_t)&uctx64, ua_uctxp, sizeof(uctx64))) {
goto bad;
}
if (copyout((caddr_t)&mctx_store, ua_mctxp, thread_state64[sig_xstate].mcontext_size)) {
goto bad;
}
sinfo64.pad[0] = tstate64->rsp;
sinfo64.si_addr = tstate64->rip;
tstate64->rip = trampact;
tstate64->rsp = ua_fp;
tstate64->rflags = get_eflags_exportmask();
/*
* SETH - need to set these for processes with LDTs
*/
tstate64->cs = USER64_CS;
tstate64->fs = NULL_SEG;
/*
* Set gs to 0 here to prevent restoration of %gs on return-to-user. If we
* did NOT do that here and %gs was non-zero, we'd blow away gsbase when
* we restore %gs in the kernel exit trampoline.
*/
tstate64->gs = 0;
if (sig_xstate & STATE64_FULL) {
/* Reset DS, ES, and possibly SS */
if (reset_ss) {
/*
* Restore %ss if (a) an altstack was used for signal delivery
* or (b) %cs at the time of the signal was the default
* (USER64_CS)
*/
mctxp->mctx_avx64_full.ss.ss = USER64_DS;
}
mctxp->mctx_avx64_full.ss.ds = USER64_DS;
mctxp->mctx_avx64_full.ss.es = 0;
}
/*
* Build the argument list for the signal handler.
* Handler should call sigreturn to get out of it
*/
tstate64->rdi = ua_catcher;
tstate64->rsi = infostyle;
tstate64->rdx = sig;
tstate64->rcx = ua_sip;
tstate64->r8 = ua_uctxp;
tstate64->r9 = token;
} else {
x86_thread_state32_t *tstate32;
struct user_ucontext32 uctx32;
struct sigframe32 frame32;
user32_addr_t token;
flavor = x86_THREAD_STATE32;
state_count = x86_THREAD_STATE32_COUNT;
state = (void *)&mctxp->mctx_avx32.ss;
if (thread_getstatus(thread, flavor, (thread_state_t)state, &state_count) != KERN_SUCCESS) {
goto bad;
}
flavor = thread_state32[sig_xstate].flavor;
state_count = thread_state32[sig_xstate].state_count;
state = (void *)&mctxp->mctx_avx32.fs;
if (thread_getstatus(thread, flavor, (thread_state_t)state, &state_count) != KERN_SUCCESS) {
goto bad;
}
flavor = x86_EXCEPTION_STATE32;
state_count = x86_EXCEPTION_STATE32_COUNT;
state = (void *)&mctxp->mctx_avx32.es;
if (thread_getstatus(thread, flavor, (thread_state_t)state, &state_count) != KERN_SUCCESS) {
goto bad;
}
tstate32 = &mctxp->mctx_avx32.ss;
/* figure out where our new stack lives */
if ((ut->uu_flag & UT_ALTSTACK) && !oonstack &&
(sigonstack)) {
ua_sp = ut->uu_sigstk.ss_sp;
stack_size = ut->uu_sigstk.ss_size;
ua_sp += stack_size;
ut->uu_sigstk.ss_flags |= SA_ONSTACK;
} else {
ua_sp = tstate32->esp;
}
ua_cr2 = mctxp->mctx_avx32.es.faultvaddr;
ua_sp -= sizeof(struct user_ucontext32);
ua_uctxp = ua_sp; // someone tramples the first word!
ua_sp -= sizeof(user32_siginfo_t);
ua_sip = ua_sp;
ua_sp -= thread_state32[sig_xstate].mcontext_size;
ua_mctxp = ua_sp;
ua_sp -= sizeof(struct sigframe32);
ua_fp = ua_sp;
/*
* Align the frame and stack pointers to 16 bytes for SSE.
* (Note that we use 'fp' as the base of the stack going forward)
*/
ua_fp = TRUNC_DOWN32(ua_fp, C_32_STK_ALIGN);
/*
* But we need to account for the return address so the alignment is
* truly "correct" at _sigtramp
*/
ua_fp -= sizeof(frame32.retaddr);
/*
* Generate the validation token for sigreturn
*/
token_uctx = ua_uctxp;
kr = machine_thread_siguctx_pointer_convert_to_user(thread, &token_uctx);
assert(kr == KERN_SUCCESS);
token = CAST_DOWN_EXPLICIT(user32_addr_t, token_uctx) ^
CAST_DOWN_EXPLICIT(user32_addr_t, ut->uu_sigreturn_token);
/*
* Build the argument list for the signal handler.
* Handler should call sigreturn to get out of it
*/
frame32.retaddr = -1;
frame32.sigstyle = infostyle;
frame32.sig = sig;
frame32.catcher = CAST_DOWN_EXPLICIT(user32_addr_t, ua_catcher);
frame32.sinfo = CAST_DOWN_EXPLICIT(user32_addr_t, ua_sip);
frame32.uctx = CAST_DOWN_EXPLICIT(user32_addr_t, ua_uctxp);
frame32.token = token;
if (copyout((caddr_t)&frame32, ua_fp, sizeof(frame32))) {
goto bad;
}
/*
* Build the signal context to be used by sigreturn.
*/
bzero(&uctx32, sizeof(uctx32));
uctx32.uc_onstack = oonstack;
uctx32.uc_sigmask = mask;
uctx32.uc_stack.ss_sp = CAST_DOWN_EXPLICIT(user32_addr_t, ua_fp);
uctx32.uc_stack.ss_size = stack_size;
if (oonstack) {
uctx32.uc_stack.ss_flags |= SS_ONSTACK;
}
uctx32.uc_link = 0;
uctx32.uc_mcsize = thread_state64[sig_xstate].mcontext_size;
uctx32.uc_mcontext = CAST_DOWN_EXPLICIT(user32_addr_t, ua_mctxp);
if (copyout((caddr_t)&uctx32, ua_uctxp, sizeof(uctx32))) {
goto bad;
}
if (copyout((caddr_t)&mctx_store, ua_mctxp, thread_state32[sig_xstate].mcontext_size)) {
goto bad;
}
sinfo64.pad[0] = tstate32->esp;
sinfo64.si_addr = tstate32->eip;
}
switch (sig) {
case SIGILL:
switch (ut->uu_code) {
case EXC_I386_INVOP:
sinfo64.si_code = ILL_ILLOPC;
break;
default:
sinfo64.si_code = ILL_NOOP;
}
break;
case SIGFPE:
#define FP_IE 0 /* Invalid operation */
#define FP_DE 1 /* Denormalized operand */
#define FP_ZE 2 /* Zero divide */
#define FP_OE 3 /* overflow */
#define FP_UE 4 /* underflow */
#define FP_PE 5 /* precision */
if (ut->uu_code == EXC_I386_DIV) {
sinfo64.si_code = FPE_INTDIV;
} else if (ut->uu_code == EXC_I386_INTO) {
sinfo64.si_code = FPE_INTOVF;
} else if (ut->uu_subcode & (1 << FP_ZE)) {
sinfo64.si_code = FPE_FLTDIV;
} else if (ut->uu_subcode & (1 << FP_OE)) {
sinfo64.si_code = FPE_FLTOVF;
} else if (ut->uu_subcode & (1 << FP_UE)) {
sinfo64.si_code = FPE_FLTUND;
} else if (ut->uu_subcode & (1 << FP_PE)) {
sinfo64.si_code = FPE_FLTRES;
} else if (ut->uu_subcode & (1 << FP_IE)) {
sinfo64.si_code = FPE_FLTINV;
} else {
sinfo64.si_code = FPE_NOOP;
}
break;
case SIGBUS:
sinfo64.si_code = BUS_ADRERR;
sinfo64.si_addr = ua_cr2;
break;
case SIGTRAP:
sinfo64.si_code = TRAP_BRKPT;
break;
case SIGSEGV:
sinfo64.si_addr = ua_cr2;
switch (ut->uu_code) {
case EXC_I386_GPFLT:
/* CR2 is meaningless after GP fault */
/* XXX namespace clash! */
sinfo64.si_addr = 0ULL;
sinfo64.si_code = 0;
break;
case KERN_PROTECTION_FAILURE:
sinfo64.si_code = SEGV_ACCERR;
break;
case KERN_INVALID_ADDRESS:
sinfo64.si_code = SEGV_MAPERR;
break;
default:
sinfo64.si_code = FPE_NOOP;
}
break;
default:
{
int status_and_exitcode;
/*
* All other signals need to fill out a minimum set of
* information for the siginfo structure passed into
* the signal handler, if SA_SIGINFO was specified.
*
* p->si_status actually contains both the status and
* the exit code; we save it off in its own variable
* for later breakdown.
*/
proc_lock(p);
sinfo64.si_pid = p->si_pid;
p->si_pid = 0;
status_and_exitcode = p->si_status;
p->si_status = 0;
sinfo64.si_uid = p->si_uid;
p->si_uid = 0;
sinfo64.si_code = p->si_code;
p->si_code = 0;
proc_unlock(p);
if (sinfo64.si_code == CLD_EXITED) {
if (WIFEXITED(status_and_exitcode)) {
sinfo64.si_code = CLD_EXITED;
} else if (WIFSIGNALED(status_and_exitcode)) {
if (WCOREDUMP(status_and_exitcode)) {
sinfo64.si_code = CLD_DUMPED;
status_and_exitcode = W_EXITCODE(status_and_exitcode, status_and_exitcode);
} else {
sinfo64.si_code = CLD_KILLED;
status_and_exitcode = W_EXITCODE(status_and_exitcode, status_and_exitcode);
}
}
}
/*
* The recorded status contains the exit code and the
* signal information, but the information to be passed
* in the siginfo to the handler is supposed to only
* contain the status, so we have to shift it out.
*/
sinfo64.si_status = (WEXITSTATUS(status_and_exitcode) & 0x00FFFFFF) | (((uint32_t)(p->p_xhighbits) << 24) & 0xFF000000);
p->p_xhighbits = 0;
break;
}
}
if (proc_is64bit(p)) {
user64_siginfo_t sinfo64_user64;
bzero((caddr_t)&sinfo64_user64, sizeof(sinfo64_user64));
siginfo_user_to_user64_x86(&sinfo64, &sinfo64_user64);
#if CONFIG_DTRACE
bzero((caddr_t)&(ut->t_dtrace_siginfo), sizeof(ut->t_dtrace_siginfo));
ut->t_dtrace_siginfo.si_signo = sinfo64.si_signo;
ut->t_dtrace_siginfo.si_code = sinfo64.si_code;
ut->t_dtrace_siginfo.si_pid = sinfo64.si_pid;
ut->t_dtrace_siginfo.si_uid = sinfo64.si_uid;
ut->t_dtrace_siginfo.si_status = sinfo64.si_status;
/* XXX truncates faulting address to void * on K32 */
ut->t_dtrace_siginfo.si_addr = CAST_DOWN(void *, sinfo64.si_addr);
/* Fire DTrace proc:::fault probe when signal is generated by hardware. */
switch (sig) {
case SIGILL: case SIGBUS: case SIGSEGV: case SIGFPE: case SIGTRAP:
DTRACE_PROC2(fault, int, (int)(ut->uu_code), siginfo_t *, &(ut->t_dtrace_siginfo));
break;
default:
break;
}
/* XXX truncates catcher address to uintptr_t */
DTRACE_PROC3(signal__handle, int, sig, siginfo_t *, &(ut->t_dtrace_siginfo),
void (*)(void), CAST_DOWN(sig_t, ua_catcher));
#endif /* CONFIG_DTRACE */
if (copyout((caddr_t)&sinfo64_user64, ua_sip, sizeof(sinfo64_user64))) {
goto bad;
}
if (sig_xstate & STATE64_FULL) {
flavor = x86_THREAD_FULL_STATE64;
state_count = x86_THREAD_FULL_STATE64_COUNT;
} else {
flavor = x86_THREAD_STATE64;
state_count = x86_THREAD_STATE64_COUNT;
}
state = (void *)&mctxp->mctx_avx64.ss;
} else {
x86_thread_state32_t *tstate32;
user32_siginfo_t sinfo32;
bzero((caddr_t)&sinfo32, sizeof(sinfo32));
siginfo_user_to_user32_x86(&sinfo64, &sinfo32);
#if CONFIG_DTRACE
bzero((caddr_t)&(ut->t_dtrace_siginfo), sizeof(ut->t_dtrace_siginfo));
ut->t_dtrace_siginfo.si_signo = sinfo32.si_signo;
ut->t_dtrace_siginfo.si_code = sinfo32.si_code;
ut->t_dtrace_siginfo.si_pid = sinfo32.si_pid;
ut->t_dtrace_siginfo.si_uid = sinfo32.si_uid;
ut->t_dtrace_siginfo.si_status = sinfo32.si_status;
ut->t_dtrace_siginfo.si_addr = CAST_DOWN(void *, sinfo32.si_addr);
/* Fire DTrace proc:::fault probe when signal is generated by hardware. */
switch (sig) {
case SIGILL: case SIGBUS: case SIGSEGV: case SIGFPE: case SIGTRAP:
DTRACE_PROC2(fault, int, (int)(ut->uu_code), siginfo_t *, &(ut->t_dtrace_siginfo));
break;
default:
break;
}
DTRACE_PROC3(signal__handle, int, sig, siginfo_t *, &(ut->t_dtrace_siginfo),
void (*)(void), CAST_DOWN(sig_t, ua_catcher));
#endif /* CONFIG_DTRACE */
if (copyout((caddr_t)&sinfo32, ua_sip, sizeof(sinfo32))) {
goto bad;
}
tstate32 = &mctxp->mctx_avx32.ss;
tstate32->eip = CAST_DOWN_EXPLICIT(user32_addr_t, trampact);
tstate32->esp = CAST_DOWN_EXPLICIT(user32_addr_t, ua_fp);
tstate32->eflags = get_eflags_exportmask();
tstate32->cs = USER_CS;
tstate32->ss = USER_DS;
tstate32->ds = USER_DS;
tstate32->es = USER_DS;
tstate32->fs = NULL_SEG;
tstate32->gs = USER_CTHREAD;
flavor = x86_THREAD_STATE32;
state_count = x86_THREAD_STATE32_COUNT;
state = (void *)tstate32;
}
if (thread_setstatus(thread, flavor, (thread_state_t)state, state_count) != KERN_SUCCESS) {
goto bad;
}
ml_fp_setvalid(FALSE);
/* Tell the PAL layer about the signal */
pal_set_signal_delivery( thread );
proc_lock(p);
return;
bad:
assert(ut->uu_pending_sigreturn > 0);
ut->uu_pending_sigreturn--;
proc_lock(p);
proc_set_sigact(p, SIGILL, SIG_DFL);
sig = sigmask(SIGILL);
p->p_sigignore &= ~sig;
p->p_sigcatch &= ~sig;
ut->uu_sigmask &= ~sig;
/* sendsig is called with signal lock held */
proc_unlock(p);
psignal_locked(p, SIGILL);
proc_lock(p);
return;
}
/*
* 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
* psl to gain improper priviledges or to cause
* a machine fault.
*/
int
sigreturn(struct proc *p, struct sigreturn_args *uap, __unused int *retval)
{
union {
struct mcontext_avx32 mctx_avx32;
struct mcontext_avx64 mctx_avx64;
struct mcontext_avx64_full mctx_avx64_full;
struct mcontext_avx512_32 mctx_avx512_32;
struct mcontext_avx512_64 mctx_avx512_64;
struct mcontext_avx512_64_full mctx_avx512_64_full;
} mctx_store, *mctxp = &mctx_store;
thread_t thread = current_thread();
struct uthread * ut;
struct sigacts *ps = &p->p_sigacts;
int error;
int onstack = 0;
mach_msg_type_number_t ts_count;
unsigned int ts_flavor;
void * ts;
mach_msg_type_number_t fs_count;
unsigned int fs_flavor;
void * fs;
int rval = EJUSTRETURN;
xstate_t sig_xstate;
uint32_t sigreturn_validation;
user_addr_t token_uctx;
kern_return_t kr;
ut = (struct uthread *)get_bsdthread_info(thread);
/* see osfmk/kern/restartable.c */
act_set_ast_reset_pcs(TASK_NULL, thread);
/*
* If we are being asked to change the altstack flag on the thread, we
* just set/reset it and return (the uap->uctx is not used).
*/
if ((unsigned int)uap->infostyle == UC_SET_ALT_STACK) {
ut->uu_sigstk.ss_flags |= SA_ONSTACK;
return 0;
} else if ((unsigned int)uap->infostyle == UC_RESET_ALT_STACK) {
ut->uu_sigstk.ss_flags &= ~SA_ONSTACK;
return 0;
}
bzero(mctxp, sizeof(*mctxp));
sig_xstate = current_xstate();
sigreturn_validation = atomic_load_explicit(
&ps->ps_sigreturn_validation, memory_order_relaxed);
token_uctx = uap->uctx;
kr = machine_thread_siguctx_pointer_convert_to_user(thread, &token_uctx);
assert(kr == KERN_SUCCESS);
if (proc_is64bit(p)) {
struct user_ucontext64 uctx64;
user64_addr_t token;
int task_has_ldt = thread_task_has_ldt(thread);
if ((error = copyin(uap->uctx, (void *)&uctx64, sizeof(uctx64)))) {
return error;
}
onstack = uctx64.uc_onstack & 01;
ut->uu_sigmask = uctx64.uc_sigmask & ~sigcantmask;
if (task_has_ldt) {
ts_flavor = x86_THREAD_FULL_STATE64;
ts_count = x86_THREAD_FULL_STATE64_COUNT;
fs = (void *)&mctxp->mctx_avx64_full.fs;
sig_xstate |= STATE64_FULL;
} else {
ts_flavor = x86_THREAD_STATE64;
ts_count = x86_THREAD_STATE64_COUNT;
fs = (void *)&mctxp->mctx_avx64.fs;
}
if ((error = copyin(uctx64.uc_mcontext64, (void *)mctxp, thread_state64[sig_xstate].mcontext_size))) {
return error;
}
ts = (void *)&mctxp->mctx_avx64.ss;
fs_flavor = thread_state64[sig_xstate].flavor;
fs_count = thread_state64[sig_xstate].state_count;
token = (user64_addr_t)token_uctx ^ (user64_addr_t)ut->uu_sigreturn_token;
if ((user64_addr_t)uap->token != token) {
#if DEVELOPMENT || DEBUG
printf("process %s[%d] sigreturn token mismatch: received 0x%llx expected 0x%llx\n",
p->p_comm, proc_getpid(p), (user64_addr_t)uap->token, token);
#endif /* DEVELOPMENT || DEBUG */
if (sigreturn_validation != PS_SIGRETURN_VALIDATION_DISABLED) {
rval = EINVAL;
}
}
} else {
struct user_ucontext32 uctx32;
user32_addr_t token;
if ((error = copyin(uap->uctx, (void *)&uctx32, sizeof(uctx32)))) {
return error;
}
if ((error = copyin(CAST_USER_ADDR_T(uctx32.uc_mcontext), (void *)mctxp, thread_state32[sig_xstate].mcontext_size))) {
return error;
}
onstack = uctx32.uc_onstack & 01;
ut->uu_sigmask = uctx32.uc_sigmask & ~sigcantmask;
ts_flavor = x86_THREAD_STATE32;
ts_count = x86_THREAD_STATE32_COUNT;
ts = (void *)&mctxp->mctx_avx32.ss;
fs_flavor = thread_state32[sig_xstate].flavor;
fs_count = thread_state32[sig_xstate].state_count;
fs = (void *)&mctxp->mctx_avx32.fs;
token = CAST_DOWN_EXPLICIT(user32_addr_t, uap->uctx) ^
CAST_DOWN_EXPLICIT(user32_addr_t, ut->uu_sigreturn_token);
if ((user32_addr_t)uap->token != token) {
#if DEVELOPMENT || DEBUG
printf("process %s[%d] sigreturn token mismatch: received 0x%x expected 0x%x\n",
p->p_comm, proc_getpid(p), (user32_addr_t)uap->token, token);
#endif /* DEVELOPMENT || DEBUG */
if (sigreturn_validation != PS_SIGRETURN_VALIDATION_DISABLED) {
rval = EINVAL;
}
}
}
if (onstack) {
ut->uu_sigstk.ss_flags |= SA_ONSTACK;
} else {
ut->uu_sigstk.ss_flags &= ~SA_ONSTACK;
}
if (ut->uu_siglist & ~ut->uu_sigmask) {
signal_setast(thread);
}
if (rval == EINVAL) {
goto error_ret;
}
/*
* thread_set_state() does all the needed checks for the passed in
* content
*/
if (thread_setstatus(thread, ts_flavor, ts, ts_count) != KERN_SUCCESS) {
rval = EINVAL;
#if DEVELOPMENT || DEBUG
printf("process %s[%d] sigreturn thread_setstatus error %d\n",
p->p_comm, proc_getpid(p), rval);
#endif /* DEVELOPMENT || DEBUG */
goto error_ret;
}
/* Decrement the pending sigreturn count */
if (ut->uu_pending_sigreturn > 0) {
ut->uu_pending_sigreturn--;
}
ml_fp_setvalid(TRUE);
if (thread_setstatus(thread, fs_flavor, fs, fs_count) != KERN_SUCCESS) {
rval = EINVAL;
#if DEVELOPMENT || DEBUG
printf("process %s[%d] sigreturn thread_setstatus error %d\n",
p->p_comm, proc_getpid(p), rval);
#endif /* DEVELOPMENT || DEBUG */
goto error_ret;
}
error_ret:
return rval;
}
/*
* machine_exception() performs machine-dependent translation
* of a mach exception to a unix signal.
*/
int
machine_exception(int exception,
mach_exception_code_t code,
__unused mach_exception_subcode_t subcode)
{
switch (exception) {
case EXC_BAD_ACCESS:
/* Map GP fault to SIGSEGV, otherwise defer to caller */
if (code == EXC_I386_GPFLT) {
return SIGSEGV;
}
break;
case EXC_BAD_INSTRUCTION:
return SIGILL;
case EXC_ARITHMETIC:
return SIGFPE;
case EXC_SOFTWARE:
if (code == EXC_I386_BOUND) {
/*
* Map #BR, the Bound Range Exceeded exception, to
* SIGTRAP.
*/
return SIGTRAP;
}
break;
}
return 0;
}
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