[sanitizer][test] Clean up allow_user_segv.cpp test case (#163870)
This test case has two issues:
- it has some special treatment of SIGBUS, ostensibly to handle old
Darwin platforms, but this been silently broken for years because the
assertions only check for SEGV.
- it has `XFAIL: !compiler-rt-optimized && tsan` [*], because the null
pointer dereference will trigger an assertion (invalid app memory)
rather than a segfault.
We fix both issues by directly raising SIGSEGV. We also considerably
simplify the test case, while maintaining the core test of chaining the
segfault handlers.
[*] This test might also fail when other sanitizer runtimes are compiled
with assertions, though those combinations are not well-tested by
buildbots.
GitOrigin-RevId: 8b74582591ba22d8e8454efe35c96fa1c393571a
diff --git a/test/sanitizer_common/TestCases/Linux/allow_user_segv.cpp b/test/sanitizer_common/TestCases/Linux/allow_user_segv.cpp
index 0c5a922..b9ce950 100644
--- a/test/sanitizer_common/TestCases/Linux/allow_user_segv.cpp
+++ b/test/sanitizer_common/TestCases/Linux/allow_user_segv.cpp
@@ -1,7 +1,5 @@
// Regression test for
// https://code.google.com/p/address-sanitizer/issues/detail?id=180
-// Fails with debug checks: https://bugs.llvm.org/show_bug.cgi?id=46860
-// XFAIL: !compiler-rt-optimized && tsan
// FIXME: Implement.
// XFAIL: hwasan
@@ -31,15 +29,12 @@
#include <stdio.h>
#include <stdlib.h>
-struct sigaction original_sigaction_sigbus;
struct sigaction original_sigaction_sigsegv;
void User_OnSIGSEGV(int signum, siginfo_t *siginfo, void *context) {
fprintf(stderr, "User sigaction called\n");
struct sigaction original_sigaction = {};
- if (signum == SIGBUS)
- original_sigaction = original_sigaction_sigbus;
- else if (signum == SIGSEGV)
+ if (signum == SIGSEGV)
original_sigaction = original_sigaction_sigsegv;
else {
printf("Invalid signum");
@@ -55,11 +50,6 @@
exit(1);
}
-int DoSEGV() {
- volatile int *x = 0;
- return *x;
-}
-
bool InstallHandler(int signum, struct sigaction *original_sigaction) {
struct sigaction user_sigaction = {};
user_sigaction.sa_sigaction = User_OnSIGSEGV;
@@ -72,13 +62,15 @@
}
int main() {
- // Let's install handlers for both SIGSEGV and SIGBUS, since pre-Yosemite
- // 32-bit Darwin triggers SIGBUS instead.
- if (InstallHandler(SIGSEGV, &original_sigaction_sigsegv) &&
- InstallHandler(SIGBUS, &original_sigaction_sigbus)) {
+ if (InstallHandler(SIGSEGV, &original_sigaction_sigsegv))
fprintf(stderr, "User sigaction installed\n");
- }
- return DoSEGV();
+
+ // Trying to organically segfault by dereferencing a pointer can be tricky
+ // when the sanitizer runtime is built with assertions. Additionally, some
+ // older platforms may SIGBUS instead.
+ raise(SIGSEGV);
+
+ return 0;
}
// CHECK0-NOT: Sanitizer:DEADLYSIGNAL
