int
swapcontext(struct thread *td, struct swapcontext_args *uap)
{
ucontext_t uc;
int ret;
if (uap->oucp == NULL || uap->ucp == NULL)
ret = EINVAL;
else {
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 = set_mcontext(td, &uc.uc_mcontext);
if (ret == 0) {
SIG_CANTMASK(uc.uc_sigmask);
PROC_LOCK(td->td_proc);
td->td_sigmask = uc.uc_sigmask;
PROC_UNLOCK(td->td_proc);
}
}
}
}
return (ret == 0 ? EJUSTRETURN : ret);
}
int
_sigsuspend(const sigset_t *set)
{
struct pthread *curthread = _get_curthread();
sigset_t oldmask, newmask, tempset;
int ret = -1;
if (curthread->attr.flags & PTHREAD_SCOPE_SYSTEM)
return (__sys_sigsuspend(set));
/* Check if a new signal set was provided by the caller: */
if (set != NULL) {
newmask = *set;
SIG_CANTMASK(newmask);
THR_LOCK_SWITCH(curthread);
/* Save current sigmask: */
oldmask = curthread->sigmask;
curthread->oldsigmask = &oldmask;
/* Change the caller's mask: */
curthread->sigmask = newmask;
tempset = curthread->sigpend;
SIGSETNAND(tempset, newmask);
if (SIGISEMPTY(tempset)) {
THR_SET_STATE(curthread, PS_SIGSUSPEND);
/* Wait for a signal: */
_thr_sched_switch_unlocked(curthread);
} else {
curthread->check_pending = 1;
THR_UNLOCK_SWITCH(curthread);
/* check pending signal I can handle: */
_thr_sig_check_pending(curthread);
}
if ((curthread->cancelflags & THR_CANCELLING) != 0)
curthread->oldsigmask = NULL;
else {
THR_ASSERT(curthread->oldsigmask == NULL,
"oldsigmask is not cleared");
}
/* Always return an interrupted error: */
errno = EINTR;
} else {
/* Return an invalid argument error: */
errno = EINVAL;
}
/* Return the completion status: */
return (ret);
}
/*
* MPSAFE
*/
int
sys_osigsetmask(struct osigsetmask_args *uap)
{
struct lwp *lp = curthread->td_lwp;
sigset_t set;
OSIG2SIG(uap->mask, set);
SIG_CANTMASK(set);
crit_enter();
SIG2OSIG(lp->lwp_sigmask, uap->sysmsg_iresult);
SIGSETLO(lp->lwp_sigmask, set);
crit_exit();
return (0);
}
/*
* Copied from amd64/amd64/machdep.c
*
* XXX fpu state need? don't think so
*/
int
linux_rt_sigreturn(struct thread *td, struct linux_rt_sigreturn_args *args)
{
struct proc *p;
struct l_ucontext uc;
struct l_sigcontext *context;
struct trapframe *regs;
unsigned long rflags;
int error;
ksiginfo_t ksi;
regs = td->td_frame;
error = copyin((void *)regs->tf_rbx, &uc, sizeof(uc));
if (error != 0)
return (error);
p = td->td_proc;
context = &uc.uc_mcontext;
rflags = context->sc_rflags;
/*
* 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_rflags for faults. Debuggers
* should sometimes set it there too. tf_rflags 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.
*/
#define RFLAG_SECURE(ef, oef) ((((ef) ^ (oef)) & ~PSL_USERCHANGE) == 0)
if (!RFLAG_SECURE(rflags & ~PSL_RF, regs->tf_rflags & ~PSL_RF)) {
printf("linux_rt_sigreturn: rflags = 0x%lx\n", rflags);
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.
*/
#define CS_SECURE(cs) (ISPL(cs) == SEL_UPL)
if (!CS_SECURE(context->sc_cs)) {
printf("linux_rt_sigreturn: cs = 0x%x\n", context->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);
}
PROC_LOCK(p);
linux_to_bsd_sigset(&uc.uc_sigmask, &td->td_sigmask);
SIG_CANTMASK(td->td_sigmask);
signotify(td);
PROC_UNLOCK(p);
regs->tf_rdi = context->sc_rdi;
regs->tf_rsi = context->sc_rsi;
regs->tf_rdx = context->sc_rdx;
regs->tf_rbp = context->sc_rbp;
regs->tf_rbx = context->sc_rbx;
regs->tf_rcx = context->sc_rcx;
regs->tf_rax = context->sc_rax;
regs->tf_rip = context->sc_rip;
regs->tf_rsp = context->sc_rsp;
regs->tf_r8 = context->sc_r8;
regs->tf_r9 = context->sc_r9;
regs->tf_r10 = context->sc_r10;
regs->tf_r11 = context->sc_r11;
regs->tf_r12 = context->sc_r12;
regs->tf_r13 = context->sc_r13;
regs->tf_r14 = context->sc_r14;
regs->tf_r15 = context->sc_r15;
regs->tf_cs = context->sc_cs;
regs->tf_err = context->sc_err;
regs->tf_rflags = rflags;
set_pcb_flags(td->td_pcb, PCB_FULL_IRET);
return (EJUSTRETURN);
}
int
sys_sigreturn(struct sigreturn_args *uap)
{
struct lwp *lp = curthread->td_lwp;
struct trapframe *regs;
ucontext_t ucp;
int cs;
int eflags;
int error;
error = copyin(uap->sigcntxp, &ucp, sizeof(ucp));
if (error)
return (error);
regs = lp->lwp_md.md_regs;
eflags = ucp.uc_mcontext.mc_eflags;
#if 0
if (eflags & PSL_VM) {
struct trapframe_vm86 *tf = (struct trapframe_vm86 *)regs;
struct vm86_kernel *vm86;
/*
* if pcb_ext == 0 or vm86_inited == 0, the user hasn't
* set up the vm86 area, and we can't enter vm86 mode.
*/
if (lp->lwp_thread->td_pcb->pcb_ext == 0)
return (EINVAL);
vm86 = &lp->lwp_thread->td_pcb->pcb_ext->ext_vm86;
if (vm86->vm86_inited == 0)
return (EINVAL);
/* go back to user mode if both flags are set */
if ((eflags & PSL_VIP) && (eflags & PSL_VIF))
trapsignal(lp->lwp_proc, SIGBUS, 0);
if (vm86->vm86_has_vme) {
eflags = (tf->tf_eflags & ~VME_USERCHANGE) |
(eflags & VME_USERCHANGE) | PSL_VM;
} else {
vm86->vm86_eflags = eflags; /* save VIF, VIP */
eflags = (tf->tf_eflags & ~VM_USERCHANGE) | (eflags & VM_USERCHANGE) | PSL_VM;
}
bcopy(&ucp.uc_mcontext.mc_gs, tf, sizeof(struct trapframe));
tf->tf_eflags = eflags;
tf->tf_vm86_ds = tf->tf_ds;
tf->tf_vm86_es = tf->tf_es;
tf->tf_vm86_fs = tf->tf_fs;
tf->tf_vm86_gs = tf->tf_gs;
tf->tf_ds = _udatasel;
tf->tf_es = _udatasel;
#if 0
tf->tf_fs = _udatasel;
tf->tf_gs = _udatasel;
#endif
} else
#endif
{
/*
* 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_eflags & ~PSL_RF)) {
kprintf("sigreturn: eflags = 0x%x\n", 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)) {
kprintf("sigreturn: cs = 0x%x\n", cs);
trapsignal(lp, SIGBUS, T_PROTFLT);
return(EINVAL);
}
bcopy(&ucp.uc_mcontext.mc_gs, regs, sizeof(struct trapframe));
}
/*
* Restore the FPU state from the frame
*/
crit_enter();
npxpop(&ucp.uc_mcontext);
if (ucp.uc_mcontext.mc_onstack & 1)
lp->lwp_sigstk.ss_flags |= SS_ONSTACK;
else
lp->lwp_sigstk.ss_flags &= ~SS_ONSTACK;
lp->lwp_sigmask = ucp.uc_sigmask;
SIG_CANTMASK(lp->lwp_sigmask);
crit_exit();
return(EJUSTRETURN);
}
