On Wed, 2017-11-15 at 13:28 +0000, Ben Hutchings wrote:
On Mon, 2017-11-13 at 19:05 +0000, Ben Hutchings wrote:
On Mon, 2017-11-06 at 10:44 +0100, Greg Kroah-Hartman wrote:
4.4-stable review patch. If anyone has any objections, please let me know.
From: Mark Rutland mark.rutland@arm.com
commit 7a7003b1da010d2b0d1dc8bf21c10f5c73b389f1 upstream.
It's possible for a user to deliberately trigger __dump_instr with a chosen kernel address.
Let's avoid problems resulting from this by using get_user() rather than __get_user(), ensuring that we don't erroneously access kernel memory.
Where we use __dump_instr() on kernel text, we already switch to KERNEL_DS, so this shouldn't adversely affect those cases.
Fixes: 60ffc30d5652810d ("arm64: Exception handling")
[...]
This seems harmless, but I don't think it will fix the bug in 4.4 unless you also cherry-pick:
commit c5cea06be060f38e5400d796e61cfc8c36e52924 Author: Mark Rutland mark.rutland@arm.com Date: Mon Jun 13 11:15:14 2016 +0100
arm64: fix dump_instr when PAN and UAO are in use
Oops, now I see you already have that as patch #36.
Only not, because I'm confusing arm and arm64.
Ben.