Messages in this thread | | | Subject | Re: [PATCH 4.4 07/40] arm64: ensure __dump_instr() checks addr_limit | From | Ben Hutchings <> | Date | Wed, 15 Nov 2017 13:36:25 +0000 |
| |
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.
-- Ben Hutchings Software Developer, Codethink Ltd.
| |