jdk/test/hotspot/jtreg/runtime/ErrorHandling/AccessZeroNKlassHitsProtectionZone.java
Roman Kennke 1e57648abd 8350457: Implement JEP 519: Compact Object Headers
Reviewed-by: mdoerr, coleenp, zgu
2025-05-22 10:48:50 +00:00

214 lines
9.6 KiB
Java

/*
* Copyright (c) 2025, Red Hat, Inc.
* Copyright (c) 2025, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
/*
* @test id=no_coh_no_cds
* @summary Test that dereferencing a Klass that is the result of a decode(0) crashes accessing the nKlass guard zone
* @library /test/lib
* @requires vm.bits == 64 & vm.debug == true & vm.flagless
* @requires os.family != "aix"
* @modules java.base/jdk.internal.misc
* java.management
* @build jdk.test.whitebox.WhiteBox
* @run driver jdk.test.lib.helpers.ClassFileInstaller jdk.test.whitebox.WhiteBox
* @run driver AccessZeroNKlassHitsProtectionZone no_coh_no_cds
*/
/*
* @test id=no_coh_cds
* @summary Test that dereferencing a Klass that is the result of a decode(0) crashes accessing the nKlass guard zone
* @requires vm.cds & vm.bits == 64 & vm.debug == true & vm.flagless
* @requires os.family != "aix"
* @library /test/lib
* @modules java.base/jdk.internal.misc
* java.management
* @build jdk.test.whitebox.WhiteBox
* @run driver jdk.test.lib.helpers.ClassFileInstaller jdk.test.whitebox.WhiteBox
* @run driver AccessZeroNKlassHitsProtectionZone no_coh_cds
*/
/*
* @test id=coh_no_cds
* @summary Test that dereferencing a Klass that is the result of a decode(0) crashes accessing the nKlass guard zone
* @requires vm.bits == 64 & vm.debug == true & vm.flagless
* @requires os.family != "aix"
* @library /test/lib
* @modules java.base/jdk.internal.misc
* java.management
* @build jdk.test.whitebox.WhiteBox
* @run driver jdk.test.lib.helpers.ClassFileInstaller jdk.test.whitebox.WhiteBox
* @run driver AccessZeroNKlassHitsProtectionZone coh_no_cds
*/
/*
* @test id=coh_cds
* @summary Test that dereferencing a Klass that is the result of a decode(0) crashes accessing the nKlass guard zone
* @requires vm.cds & vm.bits == 64 & vm.debug == true & vm.flagless
* @requires os.family != "aix"
* @library /test/lib
* @modules java.base/jdk.internal.misc
* java.management
* @build jdk.test.whitebox.WhiteBox
* @run driver jdk.test.lib.helpers.ClassFileInstaller jdk.test.whitebox.WhiteBox
* @run driver AccessZeroNKlassHitsProtectionZone coh_cds
*/
import jdk.test.lib.process.OutputAnalyzer;
import jdk.test.lib.process.ProcessTools;
import jdk.test.whitebox.WhiteBox;
import jtreg.SkippedException;
import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.regex.Pattern;
// Test that dereferencing a Klass that is the result of a narrowKlass=0 will give us immediate crashes
// that hit the protection zone at encoding base.
public class AccessZeroNKlassHitsProtectionZone {
private static OutputAnalyzer run_test(boolean COH, boolean CDS, String forceBaseString) throws IOException, SkippedException {
ArrayList<String> args = new ArrayList<>();
args.add("-Xbootclasspath/a:.");
args.add("-XX:+UnlockDiagnosticVMOptions");
args.add("-XX:+WhiteBoxAPI");
args.add("-XX:CompressedClassSpaceSize=128m");
args.add("-Xmx128m");
args.add("-XX:-CreateCoredumpOnCrash");
args.add("-Xlog:metaspace*");
args.add("-Xlog:cds");
if (COH) {
args.add("-XX:+UseCompactObjectHeaders");
}
if (CDS) {
args.add("-Xshare:on");
} else {
args.add("-Xshare:off");
args.add("-XX:CompressedClassSpaceBaseAddress=" + forceBaseString);
}
args.add(AccessZeroNKlassHitsProtectionZone.class.getName());
args.add("runwb");
ProcessBuilder pb = ProcessTools.createLimitedTestJavaProcessBuilder(args.toArray(new String[0]));
OutputAnalyzer output = new OutputAnalyzer(pb.start());
output.reportDiagnosticSummary();
return output;
}
private static void run_test(boolean COH, boolean CDS) throws IOException, SkippedException {
// Notes:
// We want to enforce zero-based encoding, to test the protection page in that case. For zero-based encoding,
// protection page is at address zero, no need to test that.
// If CDS is on, we never use zero-based, forceBase is ignored.
// If CDS is off, we use forceBase to (somewhat) reliably force the encoding base to beyond 32G,
// in order to prevent zero-based encoding. Since that may fail, we try several times.
OutputAnalyzer output = null;
long forceBase = -1;
if (CDS) {
output = run_test(COH, CDS, "");
// Not all distributions build COH archives. We tolerate that.
if (COH) {
String s = output.firstMatch("Specified shared archive file not found .*coh.jsa");
if (s != null) {
throw new SkippedException("Failed to find COH archive, was it not built? Skipping test.");
}
}
} else {
long g4 = 0x1_0000_0000L;
long start = g4 * 8; // 32g
long step = g4;
long end = start + step * 16;
for (forceBase = start; forceBase < end; forceBase += step) {
String thisBaseString = String.format("0x%016X", forceBase).toLowerCase();
output = run_test(COH, CDS, thisBaseString);
if (output.contains("CompressedClassSpaceBaseAddress=" + thisBaseString + " given, but reserving class space failed.")) {
// try next one
} else if (output.contains("Successfully forced class space address to " + thisBaseString)) {
break;
} else {
throw new RuntimeException("Unexpected");
}
}
if (forceBase >= end) {
throw new SkippedException("Failed to force ccs to any of the given bases. Skipping test.");
}
}
// Parse the encoding base from the output. In case of CDS, it depends on ASLR. Even in case of CDS=off, we want
// to double-check it is the force address.
String nKlassBaseString = output.firstMatch("Narrow klass base: 0x([0-9a-f]+)", 1);
if (nKlassBaseString == null) {
throw new RuntimeException("did not find Narrow klass base in log output");
}
long nKlassBase = Long.valueOf(nKlassBaseString, 16);
if (!CDS && nKlassBase != forceBase) {
throw new RuntimeException("Weird - we should have mapped at force base"); // .. otherwise we would have skipped out above
}
if (nKlassBase == 0) {
throw new RuntimeException("We should not be running zero-based at this point.");
}
// Calculate the expected crash address pattern. The precise crash address is unknown, but should be located
// in the lower part of the guard page following the encoding base. We just accept any address matching the
// upper 52 digits (leaving 4K = 12 bits = 4 nibbles of wiggle room)
String expectedCrashAddressString = nKlassBaseString.substring(0, nKlassBaseString.length() - 3);
// output from whitebox function: Klass* should point to encoding base
output.shouldMatch("WB_DecodeNKlassAndAccessKlass: nk 0 k 0x" + nKlassBaseString);
// Then, we should have crashed
output.shouldNotHaveExitValue(0);
output.shouldContain("# A fatal error has been detected");
// The hs-err file should contain a reference to the nKlass protection zone, like this:
// "RDI=0x0000000800000000 points into nKlass protection zone"
File hsErrFile = HsErrFileUtils.openHsErrFileFromOutput(output);
ArrayList<Pattern> hsErrPatternList = new ArrayList<>();
hsErrPatternList.add(Pattern.compile(".*(SIGBUS|SIGSEGV|EXCEPTION_ACCESS_VIOLATION).*"));
hsErrPatternList.add(Pattern.compile(".*siginfo:.*" + expectedCrashAddressString + ".*"));
hsErrPatternList.add(Pattern.compile(".*" + expectedCrashAddressString + ".*points into nKlass protection zone.*"));
Pattern[] hsErrPattern = hsErrPatternList.toArray(new Pattern[0]);
HsErrFileUtils.checkHsErrFileContent(hsErrFile, hsErrPattern, true);
}
enum Argument { runwb, no_coh_no_cds, no_coh_cds, coh_no_cds, coh_cds };
public static void main(String[] args) throws Exception {
if (args.length != 1) {
throw new RuntimeException("Expecting one argument");
}
Argument arg = Argument.valueOf(args[0]);
System.out.println(arg);
switch (arg) {
case runwb -> WhiteBox.getWhiteBox().decodeNKlassAndAccessKlass(0);
case no_coh_no_cds -> run_test(false, false);
case no_coh_cds -> run_test(false, true);
case coh_no_cds -> run_test(true, false);
case coh_cds -> run_test(true, true);
}
}
}