31906: fix race-condition interaction of $pipestatus with job control

printjob() should not reference oldjobtab for job numbers unless it is being called from bin_fg().  printjob() also must not attempt to update pipestats when called from bin_fg().  acquire_pgrp() should not loop infintely if the shell is not interactive.  Update the $pipestatus stress test so that it also exercises the oldjobtab repair.

3 files changed, 29 insertions, 5 deletions

diff --git a/ChangeLog b/ChangeLog
index 0561a3e0c..8601ba508 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,14 @@
+2013-10-26  Barton E. Schaefer  <schaefer@zsh.org>
+
+	* 31906: Src/jobs.c, Test/A05execution.ztst: printjob() should not
+	reference oldjobtab for job numbers unless it is being called from
+	bin_fg().  Add a DPUTS check in case this goes horribly wrong.
+	printjob() also must not attempt to update pipestats when called
+	from bin_fg().  Finally, acquire_pgrp() cannot acquire the tty
+	group leader if the shell is not interactive, so avoid looping
+	infinitely in the attempt.  Update the $pipestatus stress test so
+	that it also exercises the oldjobtab repair.
+
 2013-10-25  Peter Stephenson  <p.w.stephenson@ntlworld.com>
 
 	* 31890 (with Mikael's fixes in 31891): NEWS: add descriptions
diff --git a/Src/jobs.c b/Src/jobs.c
index c218743f0..336c5d4cf 100644
--- a/Src/jobs.c
+++ b/Src/jobs.c
@@ -941,10 +941,13 @@ printjob(Job jn, int lng, int synch)
     int doneprint = 0, skip_print = 0;
     FILE *fout = (synch == 2 || !shout) ? stdout : shout;
 
-    if (oldjobtab != NULL)
+    if (synch > 1 && oldjobtab != NULL)
 	job = jn - oldjobtab;
     else
 	job = jn - jobtab;
+    DPUTS3(job < 0 || job > (synch > 1 ? oldmaxjob : maxjob),
+	   "bogus job number, jn = %L, jobtab = %L, oldjobtab = %L",
+	   (long)jn, (long)jobtab, (long)oldjobtab);
 
     if (jn->stat & STAT_NOPRINT) {
 	skip_print = 1;
@@ -995,7 +998,8 @@ printjob(Job jn, int lng, int synch)
     if (skip_print) {
 	if (jn->stat & STAT_DONE) {
 	    /* This looks silly, but see update_job() */
-	    storepipestats(jn, job == thisjob, job == thisjob);
+	    if (synch <= 1)
+		storepipestats(jn, job == thisjob, job == thisjob);
 	    if (should_report_time(jn))
 		dumptime(jn);
 	    deletejob(jn, 0);
@@ -1128,7 +1132,8 @@ printjob(Job jn, int lng, int synch)
 
     if (jn->stat & STAT_DONE) {
 	/* This looks silly, but see update_job() */
-	storepipestats(jn, job == thisjob, job == thisjob);
+	if (synch <= 1)
+	    storepipestats(jn, job == thisjob, job == thisjob);
 	if (should_report_time(jn))
 	    dumptime(jn);
 	deletejob(jn, 0);
@@ -2610,6 +2615,8 @@ acquire_pgrp(void)
 	while ((ttpgrp = gettygrp()) != -1 && ttpgrp != mypgrp) {
 	    mypgrp = GETPGRP();
 	    if (mypgrp == mypid) {
+		if (!interact)
+		    break; /* attachtty() will be a no-op, give up */
 		signal_setmask(oldset);
 		attachtty(mypgrp); /* Might generate SIGT* */
 		signal_block(blockset);
diff --git a/Test/A05execution.ztst b/Test/A05execution.ztst
index 8578016ab..ba7e02cd5 100644
--- a/Test/A05execution.ztst
+++ b/Test/A05execution.ztst
@@ -179,17 +179,23 @@
 0:Status reset by starting a backgrounded command
 >0
 
-  repeat 2048; do (: | : | while false; do
+  setopt MONITOR
+  [[ -o MONITOR ]] || print -u $ZTST_fd 'Unable to change MONITOR option'
+  repeat 2048; do (return 2 |
+                   return 1 |
+                   while true; do
+                             false
                              break
                            done;
                    print "${pipestatus[@]}")
 	ZTST_hashmark
   done | sort | uniq -c | sed 's/^ *//'
 0:Check whether `$pipestatus[]' behaves.
->2048 0 0 0
+>2048 2 1 0
 F:This test checks for a bug in `$pipestatus[]' handling.  If it breaks then
 F:the bug is still there or it reappeared. See workers-29973 for details.
 
+  setopt MONITOR
   externFunc() { awk >/dev/null 2>&1; true; }
   false | true | false | true | externFunc
   echo $pipestatus