d3e991a7b6
- this panic may be unnecessarily triggered if PM gets the delayed stop signal from kernel before it gets reply from VFS to the UNPAUSE call. - after this change PM does not proceed to delivering the signal until the reply from VFS is received. Perhaps PM could deliver the signal straight away as it knows that the process does not run. Possibly i dangerous. - the signal is deliverd immediately after the UNPAUSE reply as the pending signals are always checked at the moment.
761 lines
24 KiB
C
761 lines
24 KiB
C
/* This file handles signals, which are asynchronous events and are generally
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* a messy and unpleasant business. Signals can be generated by the KILL
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* system call, or from the keyboard (SIGINT) or from the clock (SIGALRM).
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* In all cases control eventually passes to check_sig() to see which processes
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* can be signaled. The actual signaling is done by sig_proc().
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*
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* The entry points into this file are:
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* do_sigaction: perform the SIGACTION system call
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* do_sigpending: perform the SIGPENDING system call
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* do_sigprocmask: perform the SIGPROCMASK system call
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* do_sigreturn: perform the SIGRETURN system call
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* do_sigsuspend: perform the SIGSUSPEND system call
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* do_kill: perform the KILL system call
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* do_pause: perform the PAUSE system call
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* process_ksig: process a signal an behalf of the kernel
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* sig_proc: interrupt or terminate a signaled process
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* check_sig: check which processes to signal with sig_proc()
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* check_pending: check if a pending signal can now be delivered
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* restart_sigs: restart signal work after finishing a FS call
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*/
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#include "pm.h"
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#include <sys/stat.h>
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#include <sys/ptrace.h>
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#include <minix/callnr.h>
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#include <minix/endpoint.h>
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#include <minix/com.h>
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#include <minix/vm.h>
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#include <signal.h>
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#include <sys/resource.h>
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#include <sys/sigcontext.h>
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#include <string.h>
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#include "mproc.h"
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#include "param.h"
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FORWARD _PROTOTYPE( void unpause, (struct mproc *rmp) );
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FORWARD _PROTOTYPE( int sig_send, (struct mproc *rmp, int signo) );
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FORWARD _PROTOTYPE( void sig_proc_exit, (struct mproc *rmp, int signo) );
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/*===========================================================================*
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* do_sigaction *
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*===========================================================================*/
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PUBLIC int do_sigaction()
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{
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int r;
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struct sigaction svec;
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struct sigaction *svp;
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if (m_in.sig_nr == SIGKILL) return(OK);
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if (m_in.sig_nr < 1 || m_in.sig_nr >= _NSIG) return(EINVAL);
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svp = &mp->mp_sigact[m_in.sig_nr];
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if ((struct sigaction *) m_in.sig_osa != (struct sigaction *) NULL) {
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r = sys_datacopy(PM_PROC_NR,(vir_bytes) svp,
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who_e, (vir_bytes) m_in.sig_osa, (phys_bytes) sizeof(svec));
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if (r != OK) return(r);
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}
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if ((struct sigaction *) m_in.sig_nsa == (struct sigaction *) NULL)
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return(OK);
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/* Read in the sigaction structure. */
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r = sys_datacopy(who_e, (vir_bytes) m_in.sig_nsa,
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PM_PROC_NR, (vir_bytes) &svec, (phys_bytes) sizeof(svec));
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if (r != OK) return(r);
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if (svec.sa_handler == SIG_IGN) {
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sigaddset(&mp->mp_ignore, m_in.sig_nr);
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sigdelset(&mp->mp_sigpending, m_in.sig_nr);
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sigdelset(&mp->mp_catch, m_in.sig_nr);
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} else if (svec.sa_handler == SIG_DFL) {
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sigdelset(&mp->mp_ignore, m_in.sig_nr);
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sigdelset(&mp->mp_catch, m_in.sig_nr);
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} else {
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sigdelset(&mp->mp_ignore, m_in.sig_nr);
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sigaddset(&mp->mp_catch, m_in.sig_nr);
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}
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mp->mp_sigact[m_in.sig_nr].sa_handler = svec.sa_handler;
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sigdelset(&svec.sa_mask, SIGKILL);
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sigdelset(&svec.sa_mask, SIGSTOP);
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mp->mp_sigact[m_in.sig_nr].sa_mask = svec.sa_mask;
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mp->mp_sigact[m_in.sig_nr].sa_flags = svec.sa_flags;
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mp->mp_sigreturn = (vir_bytes) m_in.sig_ret;
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return(OK);
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}
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/*===========================================================================*
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* do_sigpending *
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*===========================================================================*/
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PUBLIC int do_sigpending()
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{
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mp->mp_reply.reply_mask = (long) mp->mp_sigpending;
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return OK;
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}
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/*===========================================================================*
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* do_sigprocmask *
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*===========================================================================*/
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PUBLIC int do_sigprocmask()
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{
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/* Note that the library interface passes the actual mask in sigmask_set,
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* not a pointer to the mask, in order to save a copy. Similarly,
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* the old mask is placed in the return message which the library
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* interface copies (if requested) to the user specified address.
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*
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* The library interface must set SIG_INQUIRE if the 'act' argument
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* is NULL.
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*
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* KILL and STOP can't be masked.
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*/
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int i;
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mp->mp_reply.reply_mask = (long) mp->mp_sigmask;
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switch (m_in.sig_how) {
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case SIG_BLOCK:
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sigdelset((sigset_t *)&m_in.sig_set, SIGKILL);
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sigdelset((sigset_t *)&m_in.sig_set, SIGSTOP);
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for (i = 1; i < _NSIG; i++) {
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if (sigismember((sigset_t *)&m_in.sig_set, i))
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sigaddset(&mp->mp_sigmask, i);
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}
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break;
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case SIG_UNBLOCK:
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for (i = 1; i < _NSIG; i++) {
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if (sigismember((sigset_t *)&m_in.sig_set, i))
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sigdelset(&mp->mp_sigmask, i);
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}
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check_pending(mp);
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break;
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case SIG_SETMASK:
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sigdelset((sigset_t *) &m_in.sig_set, SIGKILL);
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sigdelset((sigset_t *) &m_in.sig_set, SIGSTOP);
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mp->mp_sigmask = (sigset_t) m_in.sig_set;
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check_pending(mp);
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break;
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case SIG_INQUIRE:
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break;
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default:
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return(EINVAL);
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break;
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}
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return OK;
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}
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/*===========================================================================*
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* do_sigsuspend *
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*===========================================================================*/
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PUBLIC int do_sigsuspend()
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{
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mp->mp_sigmask2 = mp->mp_sigmask; /* save the old mask */
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mp->mp_sigmask = (sigset_t) m_in.sig_set;
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sigdelset(&mp->mp_sigmask, SIGKILL);
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sigdelset(&mp->mp_sigmask, SIGSTOP);
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mp->mp_flags |= SIGSUSPENDED;
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check_pending(mp);
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return(SUSPEND);
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}
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/*===========================================================================*
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* do_sigreturn *
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*===========================================================================*/
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PUBLIC int do_sigreturn()
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{
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/* A user signal handler is done. Restore context and check for
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* pending unblocked signals.
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*/
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int r;
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mp->mp_sigmask = (sigset_t) m_in.sig_set;
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sigdelset(&mp->mp_sigmask, SIGKILL);
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sigdelset(&mp->mp_sigmask, SIGSTOP);
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r = sys_sigreturn(who_e, (struct sigmsg *) m_in.sig_context);
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check_pending(mp);
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return(r);
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}
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/*===========================================================================*
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* do_kill *
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*===========================================================================*/
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PUBLIC int do_kill()
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{
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/* Perform the kill(pid, signo) system call. */
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return check_sig(m_in.pid, m_in.sig_nr, FALSE /* ksig */);
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}
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/*===========================================================================*
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* do_srv_kill *
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*===========================================================================*/
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PUBLIC int do_srv_kill()
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{
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/* Perform the srv_kill(pid, signo) system call. */
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/* Only RS is allowed to use srv_kill. */
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if (mp->mp_endpoint != RS_PROC_NR)
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return EPERM;
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/* Pretend the signal comes from the kernel when RS wants to deliver a signal
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* to a system process. RS sends a SIGKILL when it wants to perform cleanup.
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* In that case, ksig == TRUE forces PM to exit the process immediately.
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*/
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return check_sig(m_in.pid, m_in.sig_nr, TRUE /* ksig */);
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}
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/*===========================================================================*
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* process_ksig *
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*===========================================================================*/
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PUBLIC int process_ksig(int proc_nr_e, int signo)
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{
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register struct mproc *rmp;
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int proc_nr;
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pid_t proc_id, id;
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if(pm_isokendpt(proc_nr_e, &proc_nr) != OK || proc_nr < 0) {
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printf("PM: process_ksig: %d?? not ok\n", proc_nr_e);
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return EDEADSRCDST; /* process is gone. */
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}
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rmp = &mproc[proc_nr];
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if ((rmp->mp_flags & (IN_USE | EXITING)) != IN_USE) {
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#if 0
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printf("PM: process_ksig: %d?? exiting / not in use\n", proc_nr_e);
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#endif
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return EDEADSRCDST; /* process is gone. */
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}
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proc_id = rmp->mp_pid;
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mp = &mproc[0]; /* pretend signals are from PM */
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mp->mp_procgrp = rmp->mp_procgrp; /* get process group right */
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/* For SIGVTALRM and SIGPROF, see if we need to restart a
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* virtual timer. For SIGINT, SIGWINCH and SIGQUIT, use proc_id 0
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* to indicate a broadcast to the recipient's process group. For
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* SIGKILL, use proc_id -1 to indicate a systemwide broadcast.
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*/
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switch (signo) {
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case SIGINT:
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case SIGQUIT:
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case SIGWINCH:
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id = 0; break; /* broadcast to process group */
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case SIGVTALRM:
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case SIGPROF:
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check_vtimer(proc_nr, signo);
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/* fall-through */
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default:
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id = proc_id;
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break;
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}
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check_sig(id, signo, TRUE /* ksig */);
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/* If SIGSNDELAY is set, an earlier sys_stop() failed because the process was
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* still sending, and the kernel hereby tells us that the process is now done
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* with that. We can now try to resume what we planned to do in the first
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* place: set up a signal handler. However, the process's message may have
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* been a call to PM, in which case the process may have changed any of its
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* signal settings. The process may also have forked, exited etcetera.
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*/
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if (signo == SIGSNDELAY && (rmp->mp_flags & DELAY_CALL)) {
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rmp->mp_flags &= ~DELAY_CALL;
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/*
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* If the FS_CALL flag is still set we have a process which is stopped
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* and we only need to wait for a reply from VFS. We are going to check
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* the pending signal then
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*/
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if (rmp->mp_flags & FS_CALL)
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return OK;
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if (rmp->mp_flags & PM_SIG_PENDING)
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panic("process_ksig: bad process state");
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/* Process as many normal signals as possible. */
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check_pending(rmp);
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if (rmp->mp_flags & DELAY_CALL)
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panic("process_ksig: multiple delay calls?");
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}
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/* See if the process is still alive */
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if ((mproc[proc_nr].mp_flags & (IN_USE | EXITING)) == IN_USE) {
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return OK; /* signal has been delivered */
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}
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else {
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return EDEADSRCDST; /* process is gone */
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}
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}
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/*===========================================================================*
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* do_pause *
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*===========================================================================*/
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PUBLIC int do_pause()
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{
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/* Perform the pause() system call. */
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mp->mp_flags |= PAUSED;
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return(SUSPEND);
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}
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/*===========================================================================*
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* sig_proc *
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*===========================================================================*/
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PUBLIC void sig_proc(rmp, signo, trace, ksig)
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register struct mproc *rmp; /* pointer to the process to be signaled */
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int signo; /* signal to send to process (1 to _NSIG-1) */
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int trace; /* pass signal to tracer first? */
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int ksig; /* non-zero means signal comes from kernel */
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{
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/* Send a signal to a process. Check to see if the signal is to be caught,
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* ignored, tranformed into a message (for system processes) or blocked.
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* - If the signal is to be transformed into a message, request the KERNEL to
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* send the target process a system notification with the pending signal as an
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* argument.
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* - If the signal is to be caught, request the KERNEL to push a sigcontext
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* structure and a sigframe structure onto the catcher's stack. Also, KERNEL
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* will reset the program counter and stack pointer, so that when the process
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* next runs, it will be executing the signal handler. When the signal handler
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* returns, sigreturn(2) will be called. Then KERNEL will restore the signal
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* context from the sigcontext structure.
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* If there is insufficient stack space, kill the process.
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*/
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int r, slot, badignore;
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slot = (int) (rmp - mproc);
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if ((rmp->mp_flags & (IN_USE | EXITING)) != IN_USE) {
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printf("PM: signal %d sent to exiting process %d\n", signo, slot);
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panic("");
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}
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if (trace == TRUE && rmp->mp_tracer != NO_TRACER && signo != SIGKILL) {
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/* Signal should be passed to the debugger first.
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* This happens before any checks on block/ignore masks; otherwise,
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* the process itself could block/ignore debugger signals.
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*/
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sigaddset(&rmp->mp_sigtrace, signo);
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if (!(rmp->mp_flags & STOPPED))
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stop_proc(rmp, signo); /* a signal causes it to stop */
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return;
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}
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if (rmp->mp_flags & FS_CALL) {
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sigaddset(&rmp->mp_sigpending, signo);
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if (!(rmp->mp_flags & PM_SIG_PENDING)) {
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/* No delay calls: FS_CALL implies the process called us. */
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if ((r = sys_stop(rmp->mp_endpoint)) != OK)
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panic("sys_stop failed: %d", r);
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rmp->mp_flags |= PM_SIG_PENDING;
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}
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return;
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}
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/* Handle system signals for system processes first. */
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if(rmp->mp_flags & PRIV_PROC) {
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/* System signals have always to go through the kernel first to let it
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* pick the right signal manager. If PM is the assigned signal manager,
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* the signal will come back and will actually be processed.
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*/
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if(!ksig) {
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sys_kill(rmp->mp_endpoint, signo);
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return;
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}
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/* Print stacktrace if necessary. */
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if(SIGS_IS_STACKTRACE(signo)) {
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sys_sysctl_stacktrace(rmp->mp_endpoint);
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}
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if(!SIGS_IS_TERMINATION(signo)) {
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/* Translate every non-termination sys signal into a message. */
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message m;
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m.m_type = SIGS_SIGNAL_RECEIVED;
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m.SIGS_SIG_NUM = signo;
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asynsend3(rmp->mp_endpoint, &m, AMF_NOREPLY);
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}
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else {
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/* Exit the process in case of termination system signal. */
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sig_proc_exit(rmp, signo);
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}
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return;
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}
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/* Handle user processes now. See if the signal cannot be safely ignored. */
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badignore = ksig && sigismember(&noign_sset, signo) && (
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sigismember(&rmp->mp_ignore, signo) ||
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sigismember(&rmp->mp_sigmask, signo));
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if (!badignore && sigismember(&rmp->mp_ignore, signo)) {
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/* Signal should be ignored. */
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return;
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}
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if (!badignore && sigismember(&rmp->mp_sigmask, signo)) {
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/* Signal should be blocked. */
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sigaddset(&rmp->mp_sigpending, signo);
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return;
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}
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if ((rmp->mp_flags & STOPPED) && signo != SIGKILL) {
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/* If the process is stopped for a debugger, do not deliver any signals
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* (except SIGKILL) in order not to confuse the debugger. The signals
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* will be delivered using the check_pending() calls in do_trace().
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*/
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sigaddset(&rmp->mp_sigpending, signo);
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return;
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}
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if (!badignore && sigismember(&rmp->mp_catch, signo)) {
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/* Signal is caught. First interrupt the process's current call, if
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* applicable. This may involve a roundtrip to FS, in which case we'll
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* have to check back later.
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*/
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if (!(rmp->mp_flags & UNPAUSED)) {
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unpause(rmp);
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if (!(rmp->mp_flags & UNPAUSED)) {
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/* not yet unpaused; continue later */
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sigaddset(&rmp->mp_sigpending, signo);
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return;
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}
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}
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/* Then send the actual signal to the process, by setting up a signal
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* handler.
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*/
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if (sig_send(rmp, signo))
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return;
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/* We were unable to spawn a signal handler. Kill the process. */
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}
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else if (!badignore && sigismember(&ign_sset, signo)) {
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/* Signal defaults to being ignored. */
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return;
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}
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/* Terminate process */
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sig_proc_exit(rmp, signo);
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}
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/*===========================================================================*
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* sig_proc_exit *
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*===========================================================================*/
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PRIVATE void sig_proc_exit(rmp, signo)
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struct mproc *rmp; /* process that must exit */
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int signo; /* signal that caused termination */
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{
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rmp->mp_sigstatus = (char) signo;
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if (sigismember(&core_sset, signo)) {
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if(!(rmp->mp_flags & PRIV_PROC)) {
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printf("PM: coredump signal %d for %d / %s\n", signo,
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rmp->mp_pid, rmp->mp_name);
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sys_sysctl_stacktrace(rmp->mp_endpoint);
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}
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exit_proc(rmp, 0, TRUE /*dump_core*/);
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}
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else {
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exit_proc(rmp, 0, FALSE /*dump_core*/);
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}
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}
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/*===========================================================================*
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* check_sig *
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*===========================================================================*/
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PUBLIC int check_sig(proc_id, signo, ksig)
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pid_t proc_id; /* pid of proc to sig, or 0 or -1, or -pgrp */
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int signo; /* signal to send to process (0 to _NSIG-1) */
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int ksig; /* non-zero means signal comes from kernel */
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{
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/* Check to see if it is possible to send a signal. The signal may have to be
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* sent to a group of processes. This routine is invoked by the KILL system
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|
* call, and also when the kernel catches a DEL or other signal.
|
|
*/
|
|
|
|
register struct mproc *rmp;
|
|
int count; /* count # of signals sent */
|
|
int error_code;
|
|
|
|
if (signo < 0 || signo >= _NSIG) return(EINVAL);
|
|
|
|
/* Return EINVAL for attempts to send SIGKILL to INIT alone. */
|
|
if (proc_id == INIT_PID && signo == SIGKILL) return(EINVAL);
|
|
|
|
/* Signal RS first when broadcasting SIGTERM. */
|
|
if (proc_id == -1 && signo == SIGTERM)
|
|
sys_kill(RS_PROC_NR, signo);
|
|
|
|
/* Search the proc table for processes to signal. Start from the end of the
|
|
* table to analyze core system processes at the end when broadcasting.
|
|
* (See forkexit.c about pid magic.)
|
|
*/
|
|
count = 0;
|
|
error_code = ESRCH;
|
|
for (rmp = &mproc[NR_PROCS-1]; rmp >= &mproc[0]; rmp--) {
|
|
if (!(rmp->mp_flags & IN_USE)) continue;
|
|
|
|
/* Check for selection. */
|
|
if (proc_id > 0 && proc_id != rmp->mp_pid) continue;
|
|
if (proc_id == 0 && mp->mp_procgrp != rmp->mp_procgrp) continue;
|
|
if (proc_id == -1 && rmp->mp_pid <= INIT_PID) continue;
|
|
if (proc_id < -1 && rmp->mp_procgrp != -proc_id) continue;
|
|
|
|
/* Do not kill servers and drivers when broadcasting SIGKILL. */
|
|
if (proc_id == -1 && signo == SIGKILL &&
|
|
(rmp->mp_flags & PRIV_PROC)) continue;
|
|
|
|
/* Disallow lethal signals sent by user processes to sys processes. */
|
|
if (!ksig && SIGS_IS_LETHAL(signo) && (rmp->mp_flags & PRIV_PROC)) {
|
|
error_code = EPERM;
|
|
continue;
|
|
}
|
|
|
|
/* Check for permission. */
|
|
if (mp->mp_effuid != SUPER_USER
|
|
&& mp->mp_realuid != rmp->mp_realuid
|
|
&& mp->mp_effuid != rmp->mp_realuid
|
|
&& mp->mp_realuid != rmp->mp_effuid
|
|
&& mp->mp_effuid != rmp->mp_effuid) {
|
|
error_code = EPERM;
|
|
continue;
|
|
}
|
|
|
|
count++;
|
|
if (signo == 0 || (rmp->mp_flags & EXITING)) continue;
|
|
|
|
/* 'sig_proc' will handle the disposition of the signal. The
|
|
* signal may be caught, blocked, ignored, or cause process
|
|
* termination, possibly with core dump.
|
|
*/
|
|
sig_proc(rmp, signo, TRUE /*trace*/, ksig);
|
|
|
|
if (proc_id > 0) break; /* only one process being signaled */
|
|
}
|
|
|
|
/* If the calling process has killed itself, don't reply. */
|
|
if ((mp->mp_flags & (IN_USE | EXITING)) != IN_USE) return(SUSPEND);
|
|
return(count > 0 ? OK : error_code);
|
|
}
|
|
|
|
/*===========================================================================*
|
|
* check_pending *
|
|
*===========================================================================*/
|
|
PUBLIC void check_pending(rmp)
|
|
register struct mproc *rmp;
|
|
{
|
|
/* Check to see if any pending signals have been unblocked. Deliver as many
|
|
* of them as we can, until we have to wait for a reply from VFS first.
|
|
*
|
|
* There are several places in this file where the signal mask is
|
|
* changed. At each such place, check_pending() should be called to
|
|
* check for newly unblocked signals.
|
|
*/
|
|
|
|
int i;
|
|
|
|
for (i = 1; i < _NSIG; i++) {
|
|
if (sigismember(&rmp->mp_sigpending, i) &&
|
|
!sigismember(&rmp->mp_sigmask, i)) {
|
|
sigdelset(&rmp->mp_sigpending, i);
|
|
sig_proc(rmp, i, FALSE /*trace*/, FALSE /* ksig */);
|
|
|
|
if (rmp->mp_flags & FS_CALL)
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
/*===========================================================================*
|
|
* restart_sigs *
|
|
*===========================================================================*/
|
|
PUBLIC void restart_sigs(rmp)
|
|
struct mproc *rmp;
|
|
{
|
|
/* FS has replied to a request from us; do signal-related work.
|
|
*/
|
|
int r;
|
|
|
|
if (rmp->mp_flags & (FS_CALL | EXITING)) return;
|
|
|
|
if (rmp->mp_flags & TRACE_EXIT) {
|
|
/* Tracer requested exit with specific exit value */
|
|
exit_proc(rmp, rmp->mp_exitstatus, FALSE /*dump_core*/);
|
|
}
|
|
else if (rmp->mp_flags & PM_SIG_PENDING) {
|
|
/* We saved signal(s) for after finishing a FS call. Deal with this.
|
|
* PM_SIG_PENDING remains set to indicate the process is still stopped.
|
|
*/
|
|
check_pending(rmp);
|
|
|
|
/* The process may now be FS-blocked again, because a signal exited the
|
|
* process or was caught. Restart the process only when this is NOT the
|
|
* case.
|
|
*/
|
|
if (!(rmp->mp_flags & FS_CALL)) {
|
|
rmp->mp_flags &= ~(PM_SIG_PENDING | UNPAUSED);
|
|
|
|
if ((r = sys_resume(rmp->mp_endpoint)) != OK)
|
|
panic("sys_resume failed: %d", r);
|
|
}
|
|
}
|
|
}
|
|
|
|
/*===========================================================================*
|
|
* unpause *
|
|
*===========================================================================*/
|
|
PRIVATE void unpause(rmp)
|
|
struct mproc *rmp; /* which process */
|
|
{
|
|
/* A signal is to be sent to a process. If that process is hanging on a
|
|
* system call, the system call must be terminated with EINTR. Possible
|
|
* calls are PAUSE, WAIT, READ and WRITE, the latter two for pipes and ttys.
|
|
* First check if the process is hanging on an PM call. If not, tell FS,
|
|
* so it can check for READs and WRITEs from pipes, ttys and the like.
|
|
*/
|
|
message m;
|
|
int r;
|
|
|
|
/* If we're already waiting for a delayed call, don't do anything now. */
|
|
if (rmp->mp_flags & DELAY_CALL)
|
|
return;
|
|
|
|
/* Check to see if process is hanging on a PAUSE, WAIT or SIGSUSPEND call. */
|
|
if (rmp->mp_flags & (PAUSED | WAITING | SIGSUSPENDED)) {
|
|
/* Stop process from running. No delay calls: it called us. */
|
|
if ((r = sys_stop(rmp->mp_endpoint)) != OK)
|
|
panic("sys_stop failed: %d", r);
|
|
|
|
rmp->mp_flags |= UNPAUSED;
|
|
|
|
/* We interrupt the actual call from sig_send() below. */
|
|
return;
|
|
}
|
|
|
|
/* Not paused in PM. Let FS try to unpause the process. */
|
|
if (!(rmp->mp_flags & PM_SIG_PENDING)) {
|
|
/* Stop process from running. */
|
|
r = sys_delay_stop(rmp->mp_endpoint);
|
|
|
|
/* If the process is still busy sending a message, the kernel will give
|
|
* us EBUSY now and send a SIGSNDELAY to the process as soon as sending
|
|
* is done.
|
|
*/
|
|
if (r == EBUSY) {
|
|
rmp->mp_flags |= DELAY_CALL;
|
|
|
|
return;
|
|
}
|
|
else if (r != OK) panic("sys_stop failed: %d", r);
|
|
|
|
rmp->mp_flags |= PM_SIG_PENDING;
|
|
}
|
|
|
|
m.m_type = PM_UNPAUSE;
|
|
m.PM_PROC = rmp->mp_endpoint;
|
|
|
|
tell_fs(rmp, &m);
|
|
|
|
/* Also tell VM. */
|
|
vm_notify_sig_wrapper(rmp->mp_endpoint);
|
|
}
|
|
|
|
/*===========================================================================*
|
|
* sig_send *
|
|
*===========================================================================*/
|
|
PRIVATE int sig_send(rmp, signo)
|
|
struct mproc *rmp; /* what process to spawn a signal handler in */
|
|
int signo; /* signal to send to process (1 to _NSIG-1) */
|
|
{
|
|
/* The process is supposed to catch this signal. Spawn a signal handler.
|
|
* Return TRUE if this succeeded, FALSE otherwise.
|
|
*/
|
|
struct sigmsg sigmsg;
|
|
vir_bytes cur_sp;
|
|
int r, sigflags, slot;
|
|
|
|
if (!(rmp->mp_flags & UNPAUSED))
|
|
panic("sig_send: process not unpaused");
|
|
|
|
sigflags = rmp->mp_sigact[signo].sa_flags;
|
|
slot = (int) (rmp - mproc);
|
|
|
|
if (rmp->mp_flags & SIGSUSPENDED)
|
|
sigmsg.sm_mask = rmp->mp_sigmask2;
|
|
else
|
|
sigmsg.sm_mask = rmp->mp_sigmask;
|
|
sigmsg.sm_signo = signo;
|
|
sigmsg.sm_sighandler =
|
|
(vir_bytes) rmp->mp_sigact[signo].sa_handler;
|
|
sigmsg.sm_sigreturn = rmp->mp_sigreturn;
|
|
rmp->mp_sigmask |= rmp->mp_sigact[signo].sa_mask;
|
|
|
|
if (sigflags & SA_NODEFER)
|
|
sigdelset(&rmp->mp_sigmask, signo);
|
|
else
|
|
sigaddset(&rmp->mp_sigmask, signo);
|
|
|
|
if (sigflags & SA_RESETHAND) {
|
|
sigdelset(&rmp->mp_catch, signo);
|
|
rmp->mp_sigact[signo].sa_handler = SIG_DFL;
|
|
}
|
|
sigdelset(&rmp->mp_sigpending, signo);
|
|
|
|
if(vm_push_sig(rmp->mp_endpoint, &cur_sp) != OK)
|
|
return(FALSE);
|
|
|
|
sigmsg.sm_stkptr = cur_sp;
|
|
|
|
/* Ask the kernel to deliver the signal */
|
|
r = sys_sigsend(rmp->mp_endpoint, &sigmsg);
|
|
if (r != OK)
|
|
panic("sys_sigsend failed: %d", r);
|
|
|
|
/* Was the process suspended in PM? Then interrupt the blocking call. */
|
|
if (rmp->mp_flags & (PAUSED | WAITING | SIGSUSPENDED)) {
|
|
rmp->mp_flags &= ~(PAUSED | WAITING | SIGSUSPENDED);
|
|
|
|
setreply(slot, EINTR);
|
|
}
|
|
|
|
/* Was the process stopped just for this signal? Then resume it. */
|
|
if ((rmp->mp_flags & (PM_SIG_PENDING | UNPAUSED)) == UNPAUSED) {
|
|
rmp->mp_flags &= ~UNPAUSED;
|
|
|
|
if ((r = sys_resume(rmp->mp_endpoint)) != OK)
|
|
panic("sys_resume failed: %d", r);
|
|
}
|
|
|
|
return(TRUE);
|
|
}
|
|
|
|
/*===========================================================================*
|
|
* vm_notify_sig_wrapper *
|
|
*===========================================================================*/
|
|
PUBLIC void vm_notify_sig_wrapper(endpoint_t ep)
|
|
{
|
|
/* get IPC's endpoint,
|
|
* the reason that we directly get the endpoint
|
|
* instead of from DS server is that otherwise
|
|
* it will cause deadlock between PM, VM and DS.
|
|
*/
|
|
struct mproc *rmp;
|
|
endpoint_t ipc_ep = 0;
|
|
|
|
for (rmp = &mproc[0]; rmp < &mproc[NR_PROCS]; rmp++) {
|
|
if (!(rmp->mp_flags & IN_USE))
|
|
continue;
|
|
if (!strcmp(rmp->mp_name, "ipc")) {
|
|
ipc_ep = rmp->mp_endpoint;
|
|
vm_notify_sig(ep, ipc_ep);
|
|
|
|
return;
|
|
}
|
|
}
|
|
}
|