int
linux_sys_sigreturn(struct lwp *l, const struct linux_sys_sigreturn_args *uap, register_t *retval)
{
/* {
syscallarg(struct linux_sigframe *) sfp;
} */
struct linux_sigframe *sfp, frame;
sigset_t mask;
/*
* The trampoline code hands us the context.
* It is unsafe to keep track of it ourselves, in the event that a
* program jumps out of a signal handler.
*/
sfp = SCARG(uap, sfp);
if (ALIGN(sfp) != (u_int64_t)sfp)
return(EINVAL);
/*
* Fetch the frame structure.
*/
if (copyin((void *)sfp, &frame, sizeof(struct linux_sigframe)) != 0)
return(EFAULT);
/* Grab the signal mask. */
/* XXX use frame.extramask */
linux_old_to_native_sigset(&mask, frame.sf_sc.sc_mask);
return(linux_restore_sigcontext(l, frame.sf_sc, &mask));
}
/*
* Convert between Linux and BSD sigaction structures.
*/
void
linux_old_to_native_sigaction(struct sigaction *bsa, const struct linux_old_sigaction *lsa)
{
bsa->sa_handler = lsa->linux_sa_handler;
linux_old_to_native_sigset(&bsa->sa_mask, &lsa->linux_sa_mask);
bsa->sa_flags = linux_to_native_sigflags(lsa->linux_sa_flags);
}
int
linux_sys_sigsuspend(struct lwp *l, const struct linux_sys_sigsuspend_args *uap, register_t *retval)
{
/* {
syscallarg(void *) restart;
syscallarg(int) oldmask;
syscallarg(int) mask;
} */
linux_old_sigset_t lss;
sigset_t bss;
lss = SCARG(uap, mask);
linux_old_to_native_sigset(&bss, &lss);
return (sigsuspend1(l, &bss));
}
int
linux_sigprocmask1(struct lwp *l, int how, const linux_old_sigset_t *set, linux_old_sigset_t *oset)
{
struct proc *p = l->l_proc;
linux_old_sigset_t nlss, olss;
sigset_t nbss, obss;
int error;
switch (how) {
case LINUX_SIG_BLOCK:
how = SIG_BLOCK;
break;
case LINUX_SIG_UNBLOCK:
how = SIG_UNBLOCK;
break;
case LINUX_SIG_SETMASK:
how = SIG_SETMASK;
break;
default:
return (EINVAL);
}
if (set) {
error = copyin(set, &nlss, sizeof(nlss));
if (error)
return (error);
linux_old_to_native_sigset(&nbss, &nlss);
}
mutex_enter(p->p_lock);
error = sigprocmask1(l, how,
set ? &nbss : NULL, oset ? &obss : NULL);
mutex_exit(p->p_lock);
if (error)
return (error);
if (oset) {
native_to_linux_old_sigset(&olss, &obss);
error = copyout(&olss, oset, sizeof(olss));
if (error)
return (error);
}
return (error);
}
/*
* The following three functions fiddle with a process' signal mask.
* Convert the signal masks because of the different signal
* values for Linux. The need for this is the reason why
* they are here, and have not been mapped directly.
*/
int
linux_sys_sigsetmask(struct lwp *l, const struct linux_sys_sigsetmask_args *uap, register_t *retval)
{
/* {
syscallarg(linux_old_sigset_t) mask;
} */
sigset_t nbss, obss;
linux_old_sigset_t nlss, olss;
struct proc *p = l->l_proc;
int error;
nlss = SCARG(uap, mask);
linux_old_to_native_sigset(&nbss, &nlss);
mutex_enter(p->p_lock);
error = sigprocmask1(l, SIG_SETMASK, &nbss, &obss);
mutex_exit(p->p_lock);
if (error)
return (error);
native_to_linux_old_sigset(&olss, &obss);
*retval = olss;
return (0);
}
static int
linux_restore_sigcontext(struct lwp *l, struct linux_sigcontext *scp,
register_t *retval)
{
struct proc *p = l->l_proc;
struct sigaltstack *sas = &l->l_sigstk;
struct trapframe *tf;
sigset_t mask;
ssize_t ss_gap;
/* Restore register context. */
tf = l->l_md.md_regs;
DPRINTF(("sigreturn enter esp=0x%x eip=0x%x\n", tf->tf_esp, tf->tf_eip));
#ifdef VM86
if (scp->sc_eflags & PSL_VM) {
void syscall_vm86(struct trapframe *);
tf->tf_vm86_gs = scp->sc_gs;
tf->tf_vm86_fs = scp->sc_fs;
tf->tf_vm86_es = scp->sc_es;
tf->tf_vm86_ds = scp->sc_ds;
set_vflags(l, scp->sc_eflags);
p->p_md.md_syscall = syscall_vm86;
} else
#endif
{
/*
* Check for security violations. If we're returning to
* protected mode, the CPU will validate the segment registers
* automatically and generate a trap on violations. We handle
* the trap, rather than doing all of the checking here.
*/
if (((scp->sc_eflags ^ tf->tf_eflags) & PSL_USERSTATIC) != 0 ||
!USERMODE(scp->sc_cs, scp->sc_eflags))
return EINVAL;
tf->tf_gs = scp->sc_gs;
tf->tf_fs = scp->sc_fs;
tf->tf_es = scp->sc_es;
tf->tf_ds = scp->sc_ds;
#ifdef VM86
if (tf->tf_eflags & PSL_VM)
(*p->p_emul->e_syscall_intern)(p);
#endif
tf->tf_eflags = scp->sc_eflags;
}
tf->tf_edi = scp->sc_edi;
tf->tf_esi = scp->sc_esi;
tf->tf_ebp = scp->sc_ebp;
tf->tf_ebx = scp->sc_ebx;
tf->tf_edx = scp->sc_edx;
tf->tf_ecx = scp->sc_ecx;
tf->tf_eax = scp->sc_eax;
tf->tf_eip = scp->sc_eip;
tf->tf_cs = scp->sc_cs;
tf->tf_esp = scp->sc_esp_at_signal;
tf->tf_ss = scp->sc_ss;
/* Restore signal stack. */
/*
* Linux really does it this way; it doesn't have space in sigframe
* to save the onstack flag.
*/
mutex_enter(p->p_lock);
ss_gap = (ssize_t)((char *)scp->sc_esp_at_signal - (char *)sas->ss_sp);
if (ss_gap >= 0 && ss_gap < sas->ss_size)
sas->ss_flags |= SS_ONSTACK;
else
sas->ss_flags &= ~SS_ONSTACK;
/* Restore signal mask. */
linux_old_to_native_sigset(&mask, &scp->sc_mask);
(void) sigprocmask1(l, SIG_SETMASK, &mask, 0);
mutex_exit(p->p_lock);
DPRINTF(("sigreturn exit esp=0x%x eip=0x%x\n", tf->tf_esp, tf->tf_eip));
return EJUSTRETURN;
}
