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[libFuzzer] Don't replace custom signal handlers.
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Authored by vitalybuka on May 24 2017, 2:45 PM.

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Summary

This allows to keep handlers installed by sanitizers.
In other cases third-party code can replace handlers after libFuzzer
initialization anyway.

Build Status

Buildable 6748
Build 6748: arc lint + arc unit

LGTM with a nit.

lib/Fuzzer/FuzzerUtilPosix.cpp
60	no {}

This revision is now accepted and ready to land.May 24 2017, 6:00 PM

{}

vitalybuka marked an inline comment as done.May 24 2017, 6:43 PM

This revision was automatically updated to reflect the committed changes.

Path

Size

lib/

Fuzzer/

17 lines

test/

2 lines

	Show First 20 Lines • Show All 41 Lines • ▼ Show 20 Lines
	}			}

	static void FileSizeExceedHandler(int, siginfo_t , void ) {			static void FileSizeExceedHandler(int, siginfo_t , void ) {
	Fuzzer::StaticFileSizeExceedCallback();			Fuzzer::StaticFileSizeExceedCallback();
	}			}

	static void SetSigaction(int signum,			static void SetSigaction(int signum,
	void (callback)(int, siginfo_t , void *)) {			void (callback)(int, siginfo_t , void *)) {
	struct sigaction sigact;			struct sigaction sigact = {};
	memset(&sigact, 0, sizeof(sigact));			if (sigaction(signum, nullptr, &sigact)) {
				Printf("libFuzzer: sigaction failed with %d\n", errno);
				exit(1);
				}
				if (sigact.sa_flags & SA_SIGINFO) {
				if (sigact.sa_sigaction)
				return;
				} else {
				if (sigact.sa_handler != SIG_DFL && sigact.sa_handler != SIG_IGN &&
				sigact.sa_handler != SIG_ERR)
				kccUnsubmitted Done Reply Inline Actions no {} kcc: no {}
				return;
				}

				sigact = {};
	sigact.sa_sigaction = callback;			sigact.sa_sigaction = callback;
	if (sigaction(signum, &sigact, 0)) {			if (sigaction(signum, &sigact, 0)) {
	Printf("libFuzzer: sigaction failed with %d\n", errno);			Printf("libFuzzer: sigaction failed with %d\n", errno);
	exit(1);			exit(1);
	}			}
	}			}

	void SetTimer(int Seconds) {			void SetTimer(int Seconds) {
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	RUN: env ASAN_OPTIONS=handle_segv=0 not LLVMFuzzer-NullDerefTest 2>&1 \| FileCheck %s --check-prefix=LIBFUZZER_OWN_SEGV_HANDLER			RUN: env ASAN_OPTIONS=handle_segv=0 not LLVMFuzzer-NullDerefTest 2>&1 \| FileCheck %s --check-prefix=LIBFUZZER_OWN_SEGV_HANDLER
	LIBFUZZER_OWN_SEGV_HANDLER: == ERROR: libFuzzer: deadly signal			LIBFUZZER_OWN_SEGV_HANDLER: == ERROR: libFuzzer: deadly signal
	LIBFUZZER_OWN_SEGV_HANDLER: SUMMARY: libFuzzer: deadly signal			LIBFUZZER_OWN_SEGV_HANDLER: SUMMARY: libFuzzer: deadly signal
	LIBFUZZER_OWN_SEGV_HANDLER: Test unit written to ./crash-			LIBFUZZER_OWN_SEGV_HANDLER: Test unit written to ./crash-

				RUN: env ASAN_OPTIONS=handle_segv=1 not LLVMFuzzer-NullDerefTest 2>&1 \| FileCheck %s --check-prefix=LIBFUZZER_ASAN_SEGV_HANDLER
				LIBFUZZER_ASAN_SEGV_HANDLER: ERROR: AddressSanitizer: {{SEGV\|access-violation}} on unknown address