compiler-rt: re-exec with ASLR disabled when necessary

Some sanitizers (at least msan) currently require ASLR to be disabled.
When we detect that ASLR is enabled, re-exec with it disabled rather
than exiting with an error.  See LLVM GitHub issue 53256 for more
detail: https://github.com/llvm/llvm-project/issues/53256

No objection:	dim
MFC after:	2 weeks
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D33934

This commit is contained in:

Ed Maste

2022-01-16 14:22:05 -05:00

parent 96fe7c8ab0

commit 930a7c2ac6

1 changed files with 5 additions and 2 deletions

									
										contrib/llvm-project/compiler-rt/lib/sanitizer_common/sanitizer_linux.cpp
									
		+5
		-2
	
												View File
												
					@@ -2197,8 +2197,11 @@ void CheckASLR() {

					  }

					  }

					  if ((aslr_status & PROC_ASLR_ACTIVE) != 0) {

					  if ((aslr_status & PROC_ASLR_ACTIVE) != 0) {

					    Printf("This sanitizer is not compatible with enabled ASLR "

					    Printf("This sanitizer is not compatible with enabled ASLR "

					           "and binaries compiled with PIE\n");

					           "and binaries compiled with PIE\n"

					    Die();

					           "ASLR will be disabled and the program re-executed.\n");

					    int aslr_ctl = PROC_ASLR_FORCE_DISABLE;

					    CHECK_NE(procctl(P_PID, 0, PROC_ASLR_CTL, &aslr_ctl), -1);

					    ReExec();

					  }

					  }

					#else

					#else

					  // Do nothing

					  // Do nothing