From: Will Deacon <will.deacon@arm.com>
To: Greg KH <gregkh@linuxfoundation.org>
Cc: "Tobin C. Harding" <me@tobin.cc>, Petr Mladek <pmladek@suse.com>,
Joe Perches <joe@perches.com>, Ian Campbell <ijc@hellion.org.uk>,
Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
kernel-hardening@lists.openwall.com,
linux-kernel@vger.kernel.org,
Catalin Marinas <catalin.marinas@arm.com>,
Steven Rostedt <rostedt@goodmis.org>,
William Roberts <william.c.roberts@intel.com>,
Chris Fries <cfries@google.com>,
Dave Weinstein <olorin@google.com>
Subject: Re: [kernel-hardening] [RFC V2 2/6] lib: vsprintf: whitelist stack traces
Date: Wed, 4 Oct 2017 09:58:10 +0100 [thread overview]
Message-ID: <20171004085810.GA14022@arm.com> (raw)
In-Reply-To: <20171004085657.GC28247@kroah.com>
On Wed, Oct 04, 2017 at 10:56:57AM +0200, Greg KH wrote:
> On Mon, Oct 02, 2017 at 11:42:05AM +0100, Will Deacon wrote:
> > On Sun, Oct 01, 2017 at 11:06:46AM +1100, Tobin C. Harding wrote:
> > > Use the %pP functionality to explicitly allow kernel
> > > pointers to be logged for stack traces.
> > >
> > > Signed-off-by: Tobin C. Harding <me@tobin.cc>
> > > ---
> > > arch/arm64/kernel/traps.c | 4 ++--
> > > kernel/printk/printk.c | 2 +-
> > > 2 files changed, 3 insertions(+), 3 deletions(-)
> > >
> > > diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c
> > > index 5ea4b85..fe09660 100644
> > > --- a/arch/arm64/kernel/traps.c
> > > +++ b/arch/arm64/kernel/traps.c
> > > @@ -147,7 +147,7 @@ void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk)
> > > struct stackframe frame;
> > > int skip;
> > >
> > > - pr_debug("%s(regs = %p tsk = %p)\n", __func__, regs, tsk);
> > > + pr_debug("%s(regs = %pP tsk = %pP)\n", __func__, regs, tsk);
> >
> > Why do we care for pr_debug?
>
> Because you really want the real value? Seems to make sense to me...
Just seems like anybody debugging the kernel using pr_debug can probably
change /proc/sys/kernel/kptr_restrict...
Will
next prev parent reply other threads:[~2017-10-04 8:58 UTC|newest]
Thread overview: 68+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-10-01 0:06 [kernel-hardening] [RFC V2 0/6] add more kernel pointer filter options Tobin C. Harding
2017-10-01 0:06 ` [kernel-hardening] [RFC V2 1/6] lib: vsprintf: additional kernel pointer filtering options Tobin C. Harding
2017-10-04 8:55 ` Greg KH
2017-10-04 13:08 ` Steven Rostedt
2017-10-04 13:26 ` Greg KH
2017-10-04 13:29 ` Steven Rostedt
2017-10-04 13:54 ` Greg KH
2017-10-01 0:06 ` [kernel-hardening] [RFC V2 2/6] lib: vsprintf: whitelist stack traces Tobin C. Harding
2017-10-02 10:42 ` Will Deacon
2017-10-02 21:49 ` Tobin C. Harding
2017-10-04 8:56 ` Greg KH
2017-10-04 8:58 ` Will Deacon [this message]
2017-10-04 9:02 ` Greg KH
2017-10-04 10:42 ` Tobin C. Harding
2017-10-01 0:06 ` [kernel-hardening] [RFC V2 3/6] lib: vsprintf: physical address kernel pointer filtering options Tobin C. Harding
2017-10-04 8:58 ` Greg KH
2017-10-01 0:06 ` [kernel-hardening] [RFC V2 4/6] lib: vsprintf: default kptr_restrict to the maximum value Tobin C. Harding
2017-10-04 8:55 ` Greg KH
2017-10-04 16:42 ` Kees Cook
2017-10-04 16:48 ` Roberts, William C
2017-10-04 17:08 ` Linus Torvalds
2017-10-04 17:28 ` Linus Torvalds
2017-10-04 19:13 ` Jann Horn
2017-10-04 19:23 ` Linus Torvalds
2017-10-01 0:06 ` [kernel-hardening] [RFC V2 5/6] lib: vsprintf: add "%paP", "%papP", and "%padP" specifiers Tobin C. Harding
2017-10-04 8:58 ` Greg KH
2017-10-01 0:06 ` [kernel-hardening] [RFC V2 6/6] drivers: uio: un-restrict sysfs pointers for UIO Tobin C. Harding
2017-10-04 8:58 ` Greg KH
2017-10-01 0:11 ` [kernel-hardening] [RFC V2 0/6] add more kernel pointer filter options Tobin C. Harding
2017-10-04 8:57 ` Greg KH
2017-10-04 10:45 ` Tobin C. Harding
2017-10-04 8:58 ` Greg KH
2017-10-04 10:50 ` Tobin C. Harding
2017-10-04 12:42 ` Greg KH
2017-10-04 13:28 ` Steven Rostedt
2017-10-04 13:31 ` Steven Rostedt
2017-10-04 16:17 ` Roberts, William C
2017-10-04 15:41 ` Linus Torvalds
2017-10-04 16:22 ` Boris Lukashev
2017-10-04 16:29 ` Linus Torvalds
2017-10-04 16:54 ` Steven Rostedt
2017-10-04 18:58 ` Jordan Glover
2017-10-04 19:19 ` Linus Torvalds
2017-10-04 21:58 ` Roberts, William C
2017-10-04 23:21 ` Daniel Micay
2017-10-04 23:52 ` Linus Torvalds
2017-10-05 0:09 ` Linus Torvalds
2017-10-05 13:55 ` Bjorn Helgaas
2017-10-05 0:29 ` Daniel Micay
2017-10-05 0:35 ` Kees Cook
2017-10-06 8:33 ` Djalal Harouni
2017-10-05 2:19 ` Tobin C. Harding
2017-10-05 3:10 ` Linus Torvalds
2017-10-05 3:15 ` Kees Cook
2017-10-05 15:12 ` Roberts, William C
2017-10-05 16:19 ` Linus Torvalds
2017-10-05 17:10 ` Dave Weinstein
2017-10-07 23:44 ` Theodore Ts'o
2017-10-08 0:08 ` Linus Torvalds
2017-10-13 16:32 ` Roberts, William C
2017-10-13 18:11 ` Linus Torvalds
2017-10-13 19:34 ` Kees Cook
2017-10-13 20:22 ` Linus Torvalds
2017-10-13 20:47 ` Kees Cook
2017-10-13 21:45 ` Linus Torvalds
2017-10-13 22:48 ` Theodore Ts'o
2017-10-13 16:14 ` Roberts, William C
2017-10-04 16:32 ` Ian Campbell
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