[compiler-rt] r333985 - Introduce CheckASLR() in sanitizers
Kamil Rytarowski via llvm-commits
llvm-commits at lists.llvm.org
Tue Jun 5 00:29:24 PDT 2018
Author: kamil
Date: Tue Jun 5 00:29:23 2018
New Revision: 333985
URL: http://llvm.org/viewvc/llvm-project?rev=333985&view=rev
Log:
Introduce CheckASLR() in sanitizers
Summary:
At least the ASan, MSan, TSan sanitizers require disabled ASLR on a NetBSD.
Introduce a generic CheckASLR() routine, that implements a check for the
current process. This flag depends on the global or per-process settings.
There is no simple way to disable ASLR in the build process from the
level of a sanitizer or during the runtime execution.
With ASLR enabled sanitizers that operate over the process virtual address
space can misbehave usually breaking with cryptic messages.
This check is dummy for !NetBSD.
Sponsored by <The NetBSD Foundation>
Reviewers: vitalybuka, joerg
Reviewed By: vitalybuka
Subscribers: cryptoad, kubamracek, llvm-commits, #sanitizers
Tags: #sanitizers
Differential Revision: https://reviews.llvm.org/D47442
Modified:
compiler-rt/trunk/lib/asan/asan_rtl.cc
compiler-rt/trunk/lib/msan/msan.cc
compiler-rt/trunk/lib/sanitizer_common/sanitizer_common.h
compiler-rt/trunk/lib/sanitizer_common/sanitizer_fuchsia.cc
compiler-rt/trunk/lib/sanitizer_common/sanitizer_linux.cc
compiler-rt/trunk/lib/sanitizer_common/sanitizer_mac.cc
compiler-rt/trunk/lib/sanitizer_common/sanitizer_win.cc
compiler-rt/trunk/lib/tsan/rtl/tsan_rtl.cc
Modified: compiler-rt/trunk/lib/asan/asan_rtl.cc
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/asan/asan_rtl.cc?rev=333985&r1=333984&r2=333985&view=diff
==============================================================================
--- compiler-rt/trunk/lib/asan/asan_rtl.cc (original)
+++ compiler-rt/trunk/lib/asan/asan_rtl.cc Tue Jun 5 00:29:23 2018
@@ -384,6 +384,7 @@ static void AsanInitInternal() {
asan_init_is_running = true;
CacheBinaryName();
+ CheckASLR();
// Initialize flags. This must be done early, because most of the
// initialization steps look at flags().
Modified: compiler-rt/trunk/lib/msan/msan.cc
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/msan/msan.cc?rev=333985&r1=333984&r2=333985&view=diff
==============================================================================
--- compiler-rt/trunk/lib/msan/msan.cc (original)
+++ compiler-rt/trunk/lib/msan/msan.cc Tue Jun 5 00:29:23 2018
@@ -397,6 +397,7 @@ void __msan_init() {
InitTlsSize();
CacheBinaryName();
+ CheckASLR();
InitializeFlags();
// Install tool-specific callbacks in sanitizer_common.
Modified: compiler-rt/trunk/lib/sanitizer_common/sanitizer_common.h
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/sanitizer_common/sanitizer_common.h?rev=333985&r1=333984&r2=333985&view=diff
==============================================================================
--- compiler-rt/trunk/lib/sanitizer_common/sanitizer_common.h (original)
+++ compiler-rt/trunk/lib/sanitizer_common/sanitizer_common.h Tue Jun 5 00:29:23 2018
@@ -221,6 +221,7 @@ bool SetEnv(const char *name, const char
u32 GetUid();
void ReExec();
+void CheckASLR();
char **GetArgv();
void PrintCmdline();
bool StackSizeIsUnlimited();
Modified: compiler-rt/trunk/lib/sanitizer_common/sanitizer_fuchsia.cc
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/sanitizer_common/sanitizer_fuchsia.cc?rev=333985&r1=333984&r2=333985&view=diff
==============================================================================
--- compiler-rt/trunk/lib/sanitizer_common/sanitizer_fuchsia.cc (original)
+++ compiler-rt/trunk/lib/sanitizer_common/sanitizer_fuchsia.cc Tue Jun 5 00:29:23 2018
@@ -87,6 +87,7 @@ void GetThreadStackTopAndBottom(bool, up
}
void MaybeReexec() {}
+void CheckASLR() {}
void PlatformPrepareForSandboxing(__sanitizer_sandbox_arguments *args) {}
void DisableCoreDumperIfNecessary() {}
void InstallDeadlySignalHandlers(SignalHandlerType handler) {}
Modified: compiler-rt/trunk/lib/sanitizer_common/sanitizer_linux.cc
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/sanitizer_common/sanitizer_linux.cc?rev=333985&r1=333984&r2=333985&view=diff
==============================================================================
--- compiler-rt/trunk/lib/sanitizer_common/sanitizer_linux.cc (original)
+++ compiler-rt/trunk/lib/sanitizer_common/sanitizer_linux.cc Tue Jun 5 00:29:23 2018
@@ -1954,6 +1954,30 @@ void MaybeReexec() {
// No need to re-exec on Linux.
}
+void CheckASLR() {
+#if SANITIZER_NETBSD
+ int mib[3];
+ int paxflags;
+ size_t len = sizeof(paxflags);
+
+ mib[0] = CTL_PROC;
+ mib[1] = internal_getpid();
+ mib[2] = PROC_PID_PAXFLAGS;
+
+ if (UNLIKELY(sysctl(mib, 3, &paxflags, &len, NULL, 0) == -1)) {
+ Printf("sysctl failed\n");
+ Die();
+ }
+
+ if (UNLIKELY(paxflags & CTL_PROC_PAXFLAGS_ASLR)) {
+ Printf("This sanitizer is not compatible with enabled ASLR\n");
+ Die();
+ }
+#else
+ // Do nothing
+#endif
+}
+
void PrintModuleMap() { }
void CheckNoDeepBind(const char *filename, int flag) {
Modified: compiler-rt/trunk/lib/sanitizer_common/sanitizer_mac.cc
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/sanitizer_common/sanitizer_mac.cc?rev=333985&r1=333984&r2=333985&view=diff
==============================================================================
--- compiler-rt/trunk/lib/sanitizer_common/sanitizer_mac.cc (original)
+++ compiler-rt/trunk/lib/sanitizer_common/sanitizer_mac.cc Tue Jun 5 00:29:23 2018
@@ -340,6 +340,10 @@ void ReExec() {
UNIMPLEMENTED();
}
+void CheckASLR() {
+ // Do nothing
+}
+
uptr GetPageSize() {
return sysconf(_SC_PAGESIZE);
}
Modified: compiler-rt/trunk/lib/sanitizer_common/sanitizer_win.cc
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/sanitizer_common/sanitizer_win.cc?rev=333985&r1=333984&r2=333985&view=diff
==============================================================================
--- compiler-rt/trunk/lib/sanitizer_common/sanitizer_win.cc (original)
+++ compiler-rt/trunk/lib/sanitizer_common/sanitizer_win.cc Tue Jun 5 00:29:23 2018
@@ -1025,6 +1025,10 @@ void MaybeReexec() {
// No need to re-exec on Windows.
}
+void CheckASLR() {
+ // Do nothing
+}
+
char **GetArgv() {
// FIXME: Actually implement this function.
return 0;
Modified: compiler-rt/trunk/lib/tsan/rtl/tsan_rtl.cc
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/tsan/rtl/tsan_rtl.cc?rev=333985&r1=333984&r2=333985&view=diff
==============================================================================
--- compiler-rt/trunk/lib/tsan/rtl/tsan_rtl.cc (original)
+++ compiler-rt/trunk/lib/tsan/rtl/tsan_rtl.cc Tue Jun 5 00:29:23 2018
@@ -354,6 +354,7 @@ void Initialize(ThreadState *thr) {
ctx = new(ctx_placeholder) Context;
const char *options = GetEnv(SANITIZER_GO ? "GORACE" : "TSAN_OPTIONS");
CacheBinaryName();
+ CheckASLR();
InitializeFlags(&ctx->flags, options);
AvoidCVE_2016_2143();
InitializePlatformEarly();
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