OS-679 panic in dtrace_vcanload

5 files changed, 105 insertions, 5 deletions

diff --git a/usr/src/cmd/dtrace/test/tst/common/Makefile b/usr/src/cmd/dtrace/test/tst/common/Makefile
index 065124ada0..2ee91f15fc 100644
--- a/usr/src/cmd/dtrace/test/tst/common/Makefile
+++ b/usr/src/cmd/dtrace/test/tst/common/Makefile
@@ -97,5 +97,13 @@ usdt/tst.forker.o: usdt/forker.h
 usdt/forker.h: usdt/forker.d
 	$(DTRACE) -h -s usdt/forker.d -o usdt/forker.h
 
+ustack/tst.unpriv.exe: ustack/tst.unpriv.o ustack/unpriv_helper.o
+	$(LINK.c) -o ustack/tst.unpriv.exe \
+	    ustack/tst.unpriv.o ustack/unpriv_helper.o $(LDLIBS)
+	$(POST_PROCESS) ; $(STRIP_STABS)
+
+ustack/unpriv_helper.o: ustack/unpriv_helper.d
+	$(COMPILE.d) -o ustack/unpriv_helper.o -s ustack/unpriv_helper.d
+
 SUBDIRS = java_api
 include ../../Makefile.subdirs
diff --git a/usr/src/cmd/dtrace/test/tst/common/ustack/tst.unpriv.c b/usr/src/cmd/dtrace/test/tst/common/ustack/tst.unpriv.c
new file mode 100644
index 0000000000..43ba244444
--- /dev/null
+++ b/usr/src/cmd/dtrace/test/tst/common/ustack/tst.unpriv.c
@@ -0,0 +1,7 @@
+int
+main(int argc, char *argv[])
+{
+	for (;;)
+		;
+	return (0);
+}
diff --git a/usr/src/cmd/dtrace/test/tst/common/ustack/tst.unpriv.ksh b/usr/src/cmd/dtrace/test/tst/common/ustack/tst.unpriv.ksh
new file mode 100644
index 0000000000..26c430bff7
--- /dev/null
+++ b/usr/src/cmd/dtrace/test/tst/common/ustack/tst.unpriv.ksh
@@ -0,0 +1,68 @@
+#
+# CDDL HEADER START
+#
+# The contents of this file are subject to the terms of the
+# Common Development and Distribution License (the "License").
+# You may not use this file except in compliance with the License.
+#
+# You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+# or http://www.opensolaris.org/os/licensing.
+# See the License for the specific language governing permissions
+# and limitations under the License.
+#
+# When distributing Covered Code, include this CDDL HEADER in each
+# file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+# If applicable, add the following below this CDDL HEADER, with the
+# fields enclosed by brackets "[]" replaced with your own identifying
+# information: Portions Copyright [yyyy] [name of copyright owner]
+#
+# CDDL HEADER END
+#
+
+#
+# Copyright (c) 2011, Joyent, Inc. All rights reserved.
+#
+
+ppriv -s A=basic,dtrace_user,dtrace_proc $$
+
+if [ $# != 1 ]; then
+	echo expected one argument: '<'dtrace-path'>'
+	exit 2
+fi
+
+file=out.$$
+dtrace=$1
+
+rm -f $file
+
+dir=`/bin/dirname $tst`
+
+$dtrace -o $file -c $dir/tst.unpriv.exe -ws /dev/stdin <<EOF
+	profile-1234hz
+	/pid == \$target/
+	{
+		@[ustack(20, 8192)] = count();
+	}
+
+	tick-1s
+	{
+		secs++;
+	}
+
+	tick-1s
+	/secs > 10/
+	{
+		trace("test timed out");
+		exit(1);
+	}
+
+	profile-1234hz
+	/pid == \$target && secs > 5/
+	{
+		raise(SIGINT);
+		exit(0);
+	}
+EOF
+
+status=$?
+exit $status
diff --git a/usr/src/cmd/dtrace/test/tst/common/ustack/unpriv_helper.d b/usr/src/cmd/dtrace/test/tst/common/ustack/unpriv_helper.d
new file mode 100644
index 0000000000..eb7b0e9e9d
--- /dev/null
+++ b/usr/src/cmd/dtrace/test/tst/common/ustack/unpriv_helper.d
@@ -0,0 +1,4 @@
+dtrace:helper:ustack:
+{
+	this->otherstr = "doogle";
+}
diff --git a/usr/src/uts/common/dtrace/dtrace.c b/usr/src/uts/common/dtrace/dtrace.c
index b2f2db0c4c..eb60c15c04 100644
--- a/usr/src/uts/common/dtrace/dtrace.c
+++ b/usr/src/uts/common/dtrace/dtrace.c
@@ -745,7 +745,7 @@ static int
 dtrace_vcanload(void *src, dtrace_diftype_t *type, dtrace_mstate_t *mstate,
     dtrace_vstate_t *vstate)
 {
-	size_t sz;
+	size_t sz, strsize;
 	ASSERT(type->dtdt_flags & DIF_TF_BYREF);
 
 	/*
@@ -755,11 +755,24 @@ dtrace_vcanload(void *src, dtrace_diftype_t *type, dtrace_mstate_t *mstate,
 	if ((mstate->dtms_access & DTRACE_ACCESS_KERNEL) != 0)
 		return (1);
 
-	if (type->dtdt_kind == DIF_TYPE_STRING)
-		sz = dtrace_strlen(src,
-		    vstate->dtvs_state->dts_options[DTRACEOPT_STRSIZE]) + 1;
-	else
+	if (type->dtdt_kind == DIF_TYPE_STRING) {
+		dtrace_state_t *state = vstate->dtvs_state;
+
+		if (state != NULL) {
+			strsize = state->dts_options[DTRACEOPT_STRSIZE];
+		} else {
+			/*
+			 * In helper context, we have a NULL state; fall back
+			 * to using the system-wide default for the string size
+			 * in this case.
+			 */
+			strsize = dtrace_strsize_default;
+		}
+
+		sz = dtrace_strlen(src, strsize) + 1;
+	} else {
 		sz = type->dtdt_size;
+	}
 
 	return (dtrace_canload((uintptr_t)src, sz, mstate, vstate));
 }