[PATCH] arm64: __clear_user: handle exceptions on strb
catalin.marinas at arm.com
Thu Nov 13 07:21:15 PST 2014
On Thu, Nov 13, 2014 at 03:14:08PM +0000, Kyle McMartin wrote:
> On Thu, Nov 13, 2014 at 03:06:25PM +0000, Catalin Marinas wrote:
> > On Wed, Nov 12, 2014 at 09:07:44PM +0000, Kyle McMartin wrote:
> > > ARM64 currently doesn't fix up faults on the single-byte (strb) case of
> > > __clear_user... which means that we can cause a nasty kernel panic as an
> > > ordinary user with any multiple PAGE_SIZE+1 read from /dev/zero.
> > > i.e.: dd if=/dev/zero of=foo ibs=1 count=1 (or ibs=65537, etc.)
> > Thanks for this, it's been like this for a while. Applied.
> Thanks Catalin, if it's not too late, I forgot to add a
> Reported-by: Miloš Prchlík <mprchlik at redhat.com>
> for the initial report of the panic.
I'll add this, I haven't pushed it out yet.
More information about the linux-arm-kernel