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: e6023367d7 ("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>
This commit is contained in:
Kees Cook 2014-11-17 16:16:04 -08:00 committed by Thomas Gleixner
parent 45e2a9d470
commit 70b61e3621

View File

@ -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";
}
}
}