Patch "latent_entropy: fix ARM build error on earlier gcc" has been added to the 4.9-stable tree

Patch "latent_entropy: fix ARM build error on earlier gcc" has been added to the 4.9-stable tree

[gregkh]

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

    latent_entropy: fix ARM build error on earlier gcc

to the 4.9-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:
     latent_entropy-fix-arm-build-error-on-earlier-gcc.patch
and it can be found in the queue-4.9 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 9988f4d577f42f43b7612d755477585f35424af7 Mon Sep 17 00:00:00 2001
From: Kees Cook <keescook@chromium.org>
Date: Fri, 16 Dec 2016 12:59:31 -0800
Subject: latent_entropy: fix ARM build error on earlier gcc

From: Kees Cook <keescook@chromium.org>

commit 9988f4d577f42f43b7612d755477585f35424af7 upstream.

This fixes build errors seen on gcc-4.9.3 or gcc-5.3.1 for an ARM:

arm-soc/init/initramfs.c: In function 'error':
arm-soc/init/initramfs.c:50:1: error: unrecognizable insn:
 }
 ^
(insn 26 25 27 5 (set (reg:SI 111 [ local_entropy.243 ])
        (rotatert:SI (reg:SI 116 [ local_entropy.243 ])
            (const_int -30 [0xffffffffffffffe2]))) -1
     (nil))

Patch from PaX Team <pageexec@freemail.hu>

Reported-by: Arnd Bergmann <arnd@arndb.de>
Reported-by: Brad Spengler <spender@grsecurity.net>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 scripts/gcc-plugins/latent_entropy_plugin.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/scripts/gcc-plugins/latent_entropy_plugin.c
+++ b/scripts/gcc-plugins/latent_entropy_plugin.c
@@ -328,9 +328,9 @@ static enum tree_code get_op(tree *rhs)
 			op = LROTATE_EXPR;
 			/*
 			 * This code limits the value of random_const to
-			 * the size of a wide int for the rotation
+			 * the size of a long for the rotation
 			 */
-			random_const &= HOST_BITS_PER_WIDE_INT - 1;
+			random_const %= TYPE_PRECISION(long_unsigned_type_node);
 			break;
 		}
 


Patches currently in stable-queue which might be from keescook@chromium.org are

queue-4.9/latent_entropy-fix-arm-build-error-on-earlier-gcc.patch