Re: [PATCH V8 0/2] printk: hash addresses printed with %p

2017-11-02 Thread Vinod Koul
On Tue, Oct 31, 2017 at 04:33:13PM -0700, Joe Perches wrote: > On Wed, 2017-11-01 at 10:16 +1100, Tobin C. Harding wrote: > > Cool, thanks Joe I'll keep this in mind for when we get to %pa. > > fyi: There are more of these misuses of 0x%pa now: > > $ git grep -E -n "0[xX]%pa[dp]?\b" >

Re: [PATCH V8 0/2] printk: hash addresses printed with %p

2017-11-02 Thread Vinod Koul
On Tue, Oct 31, 2017 at 04:33:13PM -0700, Joe Perches wrote: > On Wed, 2017-11-01 at 10:16 +1100, Tobin C. Harding wrote: > > Cool, thanks Joe I'll keep this in mind for when we get to %pa. > > fyi: There are more of these misuses of 0x%pa now: > > $ git grep -E -n "0[xX]%pa[dp]?\b" >

Re: [PATCH V8 0/2] printk: hash addresses printed with %p

2017-11-02 Thread Sergey Senozhatsky
On (11/02/17 21:14), Tobin C. Harding wrote: [..] > I can put my email address if there is not a better option. sounds good. > > hm... just a huge pile of if's > > > > if (is_vmalloc_addr(addr)) > > do_hashing(addr); > > else if (__module_address(addr)) > >

Re: [PATCH V8 0/2] printk: hash addresses printed with %p

2017-11-02 Thread Sergey Senozhatsky
On (11/02/17 21:14), Tobin C. Harding wrote: [..] > I can put my email address if there is not a better option. sounds good. > > hm... just a huge pile of if's > > > > if (is_vmalloc_addr(addr)) > > do_hashing(addr); > > else if (__module_address(addr)) > >

RE: [PATCH V8 0/2] printk: hash addresses printed with %p

2017-11-02 Thread Roberts, William C
..@hellion.org.uk>; Catalin > Marinas > <catalin.mari...@arm.com>; Will Deacon <wilal.dea...@arm.com>; Steven > Rostedt <rost...@goodmis.org>; Chris Fries <cfr...@google.com>; Dave > Weinstein <olo...@google.com>; Daniel Micay <danielmi...@gmail.com>; Dja

RE: [PATCH V8 0/2] printk: hash addresses printed with %p

2017-11-02 Thread Roberts, William C
y ; Djalal > Harouni ; linux-kernel@vger.kernel.org > Subject: Re: [PATCH V8 0/2] printk: hash addresses printed with %p > > On Thu, Nov 02, 2017 at 05:23:44PM +0900, Sergey Senozhatsky wrote: > > On (11/01/17 10:35), Tobin C. Harding wrote: > > [..] > > > Yes. The qu

Re: [PATCH V8 0/2] printk: hash addresses printed with %p

2017-11-02 Thread Tobin C. Harding
On Thu, Nov 02, 2017 at 05:23:44PM +0900, Sergey Senozhatsky wrote: > On (11/01/17 10:35), Tobin C. Harding wrote: > [..] > > Yes. The question has been raised will we be here again in 6 years time > > trying to fix all the uses of %x. And there are already 29K uses of > > %[xX] in tree, which of

Re: [PATCH V8 0/2] printk: hash addresses printed with %p

2017-11-02 Thread Tobin C. Harding
On Thu, Nov 02, 2017 at 05:23:44PM +0900, Sergey Senozhatsky wrote: > On (11/01/17 10:35), Tobin C. Harding wrote: > [..] > > Yes. The question has been raised will we be here again in 6 years time > > trying to fix all the uses of %x. And there are already 29K uses of > > %[xX] in tree, which of

Re: [PATCH V8 0/2] printk: hash addresses printed with %p

2017-11-02 Thread Sergey Senozhatsky
On (11/01/17 10:35), Tobin C. Harding wrote: [..] > Yes. The question has been raised will we be here again in 6 years time > trying to fix all the uses of %x. And there are already 29K uses of > %[xX] in tree, which of these are leaking addresses? This is why Linus' > has commented that really

Re: [PATCH V8 0/2] printk: hash addresses printed with %p

2017-11-02 Thread Sergey Senozhatsky
On (11/01/17 10:35), Tobin C. Harding wrote: [..] > Yes. The question has been raised will we be here again in 6 years time > trying to fix all the uses of %x. And there are already 29K uses of > %[xX] in tree, which of these are leaking addresses? This is why Linus' > has commented that really

Re: [PATCH V8 0/2] printk: hash addresses printed with %p

2017-10-31 Thread Tobin C. Harding
On Fri, Oct 27, 2017 at 10:33:01PM +0900, Sergey Senozhatsky wrote: > On (10/26/17 13:53), Tobin C. Harding wrote: > > Currently there are many places in the kernel where addresses are being > > printed using an unadorned %p. Kernel pointers should be printed using > > %pK allowing some control

Re: [PATCH V8 0/2] printk: hash addresses printed with %p

2017-10-31 Thread Tobin C. Harding
On Fri, Oct 27, 2017 at 10:33:01PM +0900, Sergey Senozhatsky wrote: > On (10/26/17 13:53), Tobin C. Harding wrote: > > Currently there are many places in the kernel where addresses are being > > printed using an unadorned %p. Kernel pointers should be printed using > > %pK allowing some control

Re: [PATCH V8 0/2] printk: hash addresses printed with %p

2017-10-31 Thread Joe Perches
On Wed, 2017-11-01 at 10:16 +1100, Tobin C. Harding wrote: > On Mon, Oct 30, 2017 at 07:08:48PM -0700, Joe Perches wrote: > > On Tue, 2017-10-31 at 09:33 +1100, Tobin C. Harding wrote: > > > On Mon, Oct 30, 2017 at 03:03:21PM -0700, Kees Cook wrote: > > > > On Wed, Oct 25, 2017 at 7:53 PM, Tobin

Re: [PATCH V8 0/2] printk: hash addresses printed with %p

2017-10-31 Thread Joe Perches
On Wed, 2017-11-01 at 10:16 +1100, Tobin C. Harding wrote: > On Mon, Oct 30, 2017 at 07:08:48PM -0700, Joe Perches wrote: > > On Tue, 2017-10-31 at 09:33 +1100, Tobin C. Harding wrote: > > > On Mon, Oct 30, 2017 at 03:03:21PM -0700, Kees Cook wrote: > > > > On Wed, Oct 25, 2017 at 7:53 PM, Tobin

Re: [PATCH V8 0/2] printk: hash addresses printed with %p

2017-10-31 Thread Tobin C. Harding
On Mon, Oct 30, 2017 at 07:08:48PM -0700, Joe Perches wrote: > On Tue, 2017-10-31 at 09:33 +1100, Tobin C. Harding wrote: > > On Mon, Oct 30, 2017 at 03:03:21PM -0700, Kees Cook wrote: > > > On Wed, Oct 25, 2017 at 7:53 PM, Tobin C. Harding wrote: > > > > Here is the behaviour that

Re: [PATCH V8 0/2] printk: hash addresses printed with %p

2017-10-31 Thread Tobin C. Harding
On Mon, Oct 30, 2017 at 07:08:48PM -0700, Joe Perches wrote: > On Tue, 2017-10-31 at 09:33 +1100, Tobin C. Harding wrote: > > On Mon, Oct 30, 2017 at 03:03:21PM -0700, Kees Cook wrote: > > > On Wed, Oct 25, 2017 at 7:53 PM, Tobin C. Harding wrote: > > > > Here is the behaviour that this set

Re: [PATCH V8 0/2] printk: hash addresses printed with %p

2017-10-30 Thread Joe Perches
On Tue, 2017-10-31 at 09:33 +1100, Tobin C. Harding wrote: > On Mon, Oct 30, 2017 at 03:03:21PM -0700, Kees Cook wrote: > > On Wed, Oct 25, 2017 at 7:53 PM, Tobin C. Harding wrote: > > > Here is the behaviour that this set implements. > > > > > > For kpt_restrict==0 > > > > > >

Re: [PATCH V8 0/2] printk: hash addresses printed with %p

2017-10-30 Thread Joe Perches
On Tue, 2017-10-31 at 09:33 +1100, Tobin C. Harding wrote: > On Mon, Oct 30, 2017 at 03:03:21PM -0700, Kees Cook wrote: > > On Wed, Oct 25, 2017 at 7:53 PM, Tobin C. Harding wrote: > > > Here is the behaviour that this set implements. > > > > > > For kpt_restrict==0 > > > > > > Randomness not

Re: [PATCH V8 0/2] printk: hash addresses printed with %p

2017-10-30 Thread Tobin C. Harding
On Mon, Oct 30, 2017 at 03:03:21PM -0700, Kees Cook wrote: > On Wed, Oct 25, 2017 at 7:53 PM, Tobin C. Harding wrote: > > Here is the behaviour that this set implements. > > > > For kpt_restrict==0 > > > > Randomness not ready: > > printed with %p: (pointer)

Re: [PATCH V8 0/2] printk: hash addresses printed with %p

2017-10-30 Thread Tobin C. Harding
On Mon, Oct 30, 2017 at 03:03:21PM -0700, Kees Cook wrote: > On Wed, Oct 25, 2017 at 7:53 PM, Tobin C. Harding wrote: > > Here is the behaviour that this set implements. > > > > For kpt_restrict==0 > > > > Randomness not ready: > > printed with %p: (pointer) # NOTE: with

Re: [PATCH V8 0/2] printk: hash addresses printed with %p

2017-10-30 Thread Kees Cook
On Wed, Oct 25, 2017 at 7:53 PM, Tobin C. Harding wrote: > Here is the behaviour that this set implements. > > For kpt_restrict==0 > > Randomness not ready: > printed with %p: (pointer) # NOTE: with padding > Valid pointer: > printed with %pK:

Re: [PATCH V8 0/2] printk: hash addresses printed with %p

2017-10-30 Thread Kees Cook
On Wed, Oct 25, 2017 at 7:53 PM, Tobin C. Harding wrote: > Here is the behaviour that this set implements. > > For kpt_restrict==0 > > Randomness not ready: > printed with %p: (pointer) # NOTE: with padding > Valid pointer: > printed with %pK:

Re: [PATCH V8 0/2] printk: hash addresses printed with %p

2017-10-27 Thread Sergey Senozhatsky
On (10/26/17 13:53), Tobin C. Harding wrote: > Currently there are many places in the kernel where addresses are being > printed using an unadorned %p. Kernel pointers should be printed using > %pK allowing some control via the kptr_restrict sysctl. Exposing > addresses gives attackers sensitive

Re: [PATCH V8 0/2] printk: hash addresses printed with %p

2017-10-27 Thread Sergey Senozhatsky
On (10/26/17 13:53), Tobin C. Harding wrote: > Currently there are many places in the kernel where addresses are being > printed using an unadorned %p. Kernel pointers should be printed using > %pK allowing some control via the kptr_restrict sysctl. Exposing > addresses gives attackers sensitive

[PATCH V8 0/2] printk: hash addresses printed with %p

2017-10-25 Thread Tobin C. Harding
Currently there are many places in the kernel where addresses are being printed using an unadorned %p. Kernel pointers should be printed using %pK allowing some control via the kptr_restrict sysctl. Exposing addresses gives attackers sensitive information about the kernel layout in memory. We can

[PATCH V8 0/2] printk: hash addresses printed with %p

2017-10-25 Thread Tobin C. Harding
Currently there are many places in the kernel where addresses are being printed using an unadorned %p. Kernel pointers should be printed using %pK allowing some control via the kptr_restrict sysctl. Exposing addresses gives attackers sensitive information about the kernel layout in memory. We can