abe@mace.cc.purdue.edu (Vic Abell) (01/04/89)
The rlogin supplied with SunOS 4.0 will dump core if it receives an
out-of-band signal (SIGURG) during startup. This happens because rlogin
enables the handling of the SIGURG signal before it initializes a jump
buffer that the SIGURG handler exits through with a long jump. The
attached context diffs to /usr/src/ucb/rlogin.c fix the problem.
*** rlogin.c.orig Wed Dec 21 11:10:05 1988
--- /usr/src/ucb/rlogin.c Thu Dec 22 11:06:25 1988
***************
*** 39,44 ****
--- 39,45 ----
int rem;
char cmdchar = '~';
int eight;
+ jmp_buf rcvtop;
int litout;
char *speeds[] =
{ "0", "50", "75", "110", "134", "150", "200", "300",
***************
*** 126,132 ****
}
(void) ioctl(0, TIOCGWINSZ, &winsize);
signal(SIGPIPE, lostpeer);
! signal(SIGURG, oob);
oldmask = sigblock(sigmask(SIGURG));
rem = rcmd(&host, htons(port_number), pwd->pw_name,
name ? name : pwd->pw_name, term, 0);
--- 127,134 ----
}
(void) ioctl(0, TIOCGWINSZ, &winsize);
signal(SIGPIPE, lostpeer);
! if (setjmp(rcvtop) == 0)
! signal(SIGURG, oob);
oldmask = sigblock(sigmask(SIGURG));
rem = rcmd(&host, htons(port_number), pwd->pw_name,
name ? name : pwd->pw_name, term, 0);
***************
*** 188,195 ****
}
if (child == 0) {
mode(1);
! sigsetmask(oldmask);
! if (reader() == 0) {
prf("Connection closed.");
exit(0);
}
--- 190,196 ----
}
if (child == 0) {
mode(1);
! if (reader(oldmask) == 0) {
prf("Connection closed.");
exit(0);
}
***************
*** 394,401 ****
char rcvbuf[8 * 1024];
int rcvcnt;
int rcvstate;
! int ppid;
! jmp_buf rcvtop;
oob()
{
--- 395,401 ----
char rcvbuf[8 * 1024];
int rcvcnt;
int rcvstate;
! int ppid = -1;
oob()
{
***************
*** 434,440 ****
/*
* Let server know about window size changes
*/
! kill(ppid, SIGURG);
}
if (!eight && (mark & TIOCPKT_NOSTOP)) {
ioctl(0, TIOCGETP, (char *)&sb);
--- 434,441 ----
/*
* Let server know about window size changes
*/
! if (ppid != -1)
! kill(ppid, SIGURG);
}
if (!eight && (mark & TIOCPKT_NOSTOP)) {
ioctl(0, TIOCGETP, (char *)&sb);
***************
*** 493,499 ****
/*
* reader: read from remote: line -> 1
*/
! reader()
{
/*
* 4.3bsd or later and SunOS 4.0 or later use the second
--- 494,500 ----
/*
* reader: read from remote: line -> 1
*/
! reader(oldmask)
{
/*
* 4.3bsd or later and SunOS 4.0 or later use the second
***************
*** 507,516 ****
int n, remaining;
char *bufp = rcvbuf;
- signal(SIGTTOU, SIG_IGN);
- fcntl(rem, F_SETOWN, pid);
ppid = getppid();
! (void) setjmp(rcvtop);
for (;;) {
while ((remaining = rcvcnt - (bufp - rcvbuf)) > 0) {
rcvstate = WRITING;
--- 508,519 ----
int n, remaining;
char *bufp = rcvbuf;
ppid = getppid();
! if (setjmp(rcvtop) == 0) {
! signal(SIGTTOU, SIG_IGN);
! sigsetmask(oldmask);
! fcntl(rem, F_SETOWN, pid);
! }
for (;;) {
while ((remaining = rcvcnt - (bufp - rcvbuf)) > 0) {
rcvstate = WRITING;