svn commit: r361646 - in stable/12/bin/sh: . tests/execution

[Jilles Tjoelker]

Author: jilles
Date: Sat May 30 13:39:56 2020
New Revision: 361646
URL: https://svnweb.freebsd.org/changeset/base/361646

Log:
  MFC r361112,r361117: sh: Fix double INTON with vfork
  
  The shell maintains a count of the number of times SIGINT processing has
  been disabled via INTOFF, so SIGINT processing resumes when all disables
  have enabled again (INTON).
  
  If an error occurs in a vfork() child, the processing of the error enables
  SIGINT processing again, and the INTON in vforkexecshell() causes the count
  to become negative.
  
  As a result, a later INTOFF may not actually disable SIGINT processing. This
  might cause memory corruption if a SIGINT arrives at an inopportune time.
  
  Note that various places such as errors in non-special builtins
  unconditionally reset the count to 0, so the problem might still not always
  be visible.
  
  PR:		246497

Added:
     - copied unchanged from r361112, head/bin/sh/tests/execution/unknown2.0
Directory Properties:
  stable/12/bin/sh/tests/execution/unknown2.0   (props changed)
Modified:
  stable/12/bin/sh/jobs.c
  stable/12/bin/sh/tests/execution/Makefile
Directory Properties:
  stable/12/   (props changed)

Modified: stable/12/bin/sh/jobs.c
==============================================================================
--- stable/12/bin/sh/jobs.c	Sat May 30 02:56:13 2020	(r361645)
+++ stable/12/bin/sh/jobs.c	Sat May 30 13:39:56 2020	(r361646)
@@ -1007,9 +1007,11 @@ vforkexecshell(struct job *jp, char **argv, char **env
 	pid_t pid;
 	struct jmploc jmploc;
 	struct jmploc *savehandler;
+	int inton;
 
 	TRACE(("vforkexecshell(%%%td, %s, %p) called\n", jp - jobtab, argv[0],
 	    (void *)pip));
+	inton = is_int_on();
 	INTOFF;
 	flushall();
 	savehandler = handler;
@@ -1044,7 +1046,7 @@ vforkexecshell(struct job *jp, char **argv, char **env
 		setcurjob(jp);
 #endif
 	}
-	INTON;
+	SETINTON(inton);
 	TRACE(("In parent shell:  child = %d\n", (int)pid));
 	return pid;
 }

Modified: stable/12/bin/sh/tests/execution/Makefile
==============================================================================
--- stable/12/bin/sh/tests/execution/Makefile	Sat May 30 02:56:13 2020	(r361645)
+++ stable/12/bin/sh/tests/execution/Makefile	Sat May 30 13:39:56 2020	(r361646)
@@ -59,6 +59,7 @@ ${PACKAGE}FILES+=		subshell2.0
 ${PACKAGE}FILES+=		subshell3.0
 ${PACKAGE}FILES+=		subshell4.0
 ${PACKAGE}FILES+=		unknown1.0
+${PACKAGE}FILES+=		unknown2.0
 ${PACKAGE}FILES+=		var-assign1.0
 
 .include <bsd.test.mk>

Copied: stable/12/bin/sh/tests/execution/unknown2.0 (from r361112, head/bin/sh/tests/execution/unknown2.0)
==============================================================================
--- /dev/null	00:00:00 1970	(empty, because file is newly added)
+++ stable/12/bin/sh/tests/execution/unknown2.0	Sat May 30 13:39:56 2020	(r361646, copy of r361112, head/bin/sh/tests/execution/unknown2.0)
@@ -0,0 +1,6 @@
+# $FreeBSD$
+
+{
+	: $(/var/empty/nosuchtool) 
+	: $(:)
+} 2>/dev/null