Patch "arm64: vmlinux.lds: make __rela_offset and __dynsym_offset ABSOLUTE" has been added to the 4.7-stable tree

Patch "arm64: vmlinux.lds: make __rela_offset and __dynsym_offset ABSOLUTE" has been added to the 4.7-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    arm64: vmlinux.lds: make __rela_offset and __dynsym_offset ABSOLUTE

to the 4.7-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     arm64-vmlinux.lds-make-__rela_offset-and-__dynsym_offset-absolute.patch
and it can be found in the queue-4.7 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From d6732fc402c2665f61e72faf206a0268e65236e9 Mon Sep 17 00:00:00 2001
From: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Date: Thu, 28 Jul 2016 16:15:14 +0200
Subject: arm64: vmlinux.lds: make __rela_offset and __dynsym_offset ABSOLUTE

From: Ard Biesheuvel <ard.biesheuvel@linaro.org>

commit d6732fc402c2665f61e72faf206a0268e65236e9 upstream.

Due to the untyped KIMAGE_VADDR constant, the linker may not notice
that the __rela_offset and __dynsym_offset expressions are absolute
values (i.e., are not subject to relocation). This does not matter for
KASLR, but it does confuse kallsyms in relative mode, since it uses
the lowest non-absolute symbol address as the anchor point, and expects
all other symbol addresses to be within 4 GB of it.

Fix this by qualifying these expressions as ABSOLUTE() explicitly.

Fixes: 0cd3defe0af4 ("arm64: kernel: perform relocation processing from ID map")
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 arch/arm64/kernel/vmlinux.lds.S |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/arch/arm64/kernel/vmlinux.lds.S
+++ b/arch/arm64/kernel/vmlinux.lds.S
@@ -181,9 +181,9 @@ SECTIONS
 		*(.hash)
 	}
 
-	__rela_offset	= ADDR(.rela) - KIMAGE_VADDR;
+	__rela_offset	= ABSOLUTE(ADDR(.rela) - KIMAGE_VADDR);
 	__rela_size	= SIZEOF(.rela);
-	__dynsym_offset	= ADDR(.dynsym) - KIMAGE_VADDR;
+	__dynsym_offset	= ABSOLUTE(ADDR(.dynsym) - KIMAGE_VADDR);
 
 	. = ALIGN(SEGMENT_ALIGN);
 	__init_end = .;


Patches currently in stable-queue which might be from ard.biesheuvel@linaro.org are

queue-4.7/arm64-only-select-arm64_module_plts-if-modules-y.patch
queue-4.7/arm64-vmlinux.lds-make-__rela_offset-and-__dynsym_offset-absolute.patch
queue-4.7/arm64-mm-avoid-fdt_check_header-before-the-fdt-is-fully-mapped.patch