Commit 70b61e36 authored Nov 17, 2014 by Kees Cook Committed by Thomas Gleixner Nov 18, 2014

x86, kaslr: Handle Gold linker for finding bss/brk



When building with the Gold linker, the .bss and .brk areas of vmlinux
are shown as consecutive instead of having the same file offset. Allow
for either state, as long as things add up correctly.

Fixes: e6023367 ("x86, kaslr: Prevent .bss from overlaping initrd")
Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Junjie Mao <eternal.n08@gmail.com>
Link: http://lkml.kernel.org/r/20141118001604.GA25045@www.outflux.net


Cc: stable@vger.kernel.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

parent 45e2a9d4

arch/x86/tools/calc_run_size.pl

+10 −1

Original line number	Diff line number	Diff line
		@@ -19,7 +19,16 @@ while (<>) {
		if ($file_offset == 0) {
		$file_offset = $offset;
		} elsif ($file_offset != $offset) {
		die ".bss and .brk lack common file offset\n";
		# BFD linker shows the same file offset in ELF.
		# Gold linker shows them as consecutive.
		next if ($file_offset + $mem_size == $offset + $size);

		printf STDERR "file_offset: 0x%lx\n", $file_offset;
		printf STDERR "mem_size: 0x%lx\n", $mem_size;
		printf STDERR "offset: 0x%lx\n", $offset;
		printf STDERR "size: 0x%lx\n", $size;

		die ".bss and .brk are non-contiguous\n";
		}
		}
		}

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