From: Ingo Molnar <mingo@kernel.org>
To: "Reshetova, Elena" <elena.reshetova@intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>,
"luto@kernel.org" <luto@kernel.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"luto@amacapital.net" <luto@amacapital.net>,
"keescook@chromium.org" <keescook@chromium.org>,
"jannh@google.com" <jannh@google.com>,
"Perla, Enrico" <enrico.perla@intel.com>,
"mingo@redhat.com" <mingo@redhat.com>,
"bp@alien8.de" <bp@alien8.de>,
"tglx@linutronix.de" <tglx@linutronix.de>,
"peterz@infradead.org" <peterz@infradead.org>,
"gregkh@linuxfoundation.org" <gregkh@linuxfoundation.org>
Subject: Re: [PATCH] x86/entry/64: randomize kernel stack offset upon syscall
Date: Wed, 10 Apr 2019 12:17:33 +0200 [thread overview]
Message-ID: <20190410101733.GA2045@gmail.com> (raw)
In-Reply-To: <2236FBA76BA1254E88B949DDB74E612BA4C48943@IRSMSX102.ger.corp.intel.com>
* Reshetova, Elena <elena.reshetova@intel.com> wrote:
> > * Josh Poimboeuf <jpoimboe@redhat.com> wrote:
> >
> > > On Mon, Apr 08, 2019 at 09:13:58AM +0300, Elena Reshetova wrote:
> > > > diff --git a/arch/x86/entry/common.c b/arch/x86/entry/common.c
> > > > index 7bc105f47d21..38ddc213a5e9 100644
> > > > --- a/arch/x86/entry/common.c
> > > > +++ b/arch/x86/entry/common.c
> > > > @@ -35,6 +35,12 @@
> > > > #define CREATE_TRACE_POINTS
> > > > #include <trace/events/syscalls.h>
> > > >
> > > > +#ifdef CONFIG_RANDOMIZE_KSTACK_OFFSET
> > > > +#include <linux/random.h>
> > > > +
> > > > +void *alloca(size_t size);
> > > > +#endif
> > > > +
> > > > #ifdef CONFIG_CONTEXT_TRACKING
> > > > /* Called on entry from user mode with IRQs off. */
> > > > __visible inline void enter_from_user_mode(void)
> > > > @@ -273,6 +279,13 @@ __visible void do_syscall_64(unsigned long nr, struct
> > pt_regs *regs)
> > > > {
> > > > struct thread_info *ti;
> > > >
> > > > +#ifdef CONFIG_RANDOMIZE_KSTACK_OFFSET
> > > > + size_t offset = ((size_t)prandom_u32()) % 256;
> > > > + char *ptr = alloca(offset);
> > > > +
> > > > + asm volatile("":"=m"(*ptr));
> > > > +#endif
> > > > +
> > > > enter_from_user_mode();
> > > > local_irq_enable();
> > > > ti = current_thread_info();
> > >
> > > Would it make sense to also do this for the compat syscalls
> > > (do_fast_syscall_32, do_int80_syscall_32)?
> >
> > Could someone please include the full patch, with justification and
> > performance impact analysis etc.? Can only find the code part of the
> > thread on lkml, which leaves out this context.
> >
>
> Sorry, this is very weird, I cannot find it either from lkml, but it was sent there
> to begin with (and as visible from reply-to headers).
>
> Do you want me to resent original version or with "do_fast_syscall_32,
> do_int80_syscall_32" additions (I am finishing testing them now).
The original patch would be fine to me, was missing the context.
Thanks,
Ingo
next prev parent reply other threads:[~2019-04-10 10:17 UTC|newest]
Thread overview: 81+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20190408061358.21288-1-elena.reshetova@intel.com>
2019-04-08 12:49 ` [PATCH] x86/entry/64: randomize kernel stack offset upon syscall Josh Poimboeuf
2019-04-08 13:30 ` Reshetova, Elena
2019-04-08 16:21 ` Kees Cook
2019-04-10 8:26 ` Ingo Molnar
2019-04-10 9:00 ` Reshetova, Elena
2019-04-10 10:17 ` Ingo Molnar [this message]
2019-04-10 10:24 ` Reshetova, Elena
2019-04-10 14:52 ` Andy Lutomirski
2019-04-12 5:36 ` Reshetova, Elena
2019-04-12 21:16 ` Andy Lutomirski
2019-04-15 6:09 Elena Reshetova
2019-04-15 7:25 ` Ingo Molnar
2019-04-15 8:44 ` Reshetova, Elena
2019-04-16 7:34 ` Ingo Molnar
2019-04-16 11:10 ` Reshetova, Elena
2019-04-16 12:08 ` Peter Zijlstra
2019-04-16 12:45 ` David Laight
2019-04-16 15:43 ` Theodore Ts'o
2019-04-16 16:07 ` Peter Zijlstra
2019-04-16 16:47 ` Reshetova, Elena
2019-04-17 9:28 ` David Laight
2019-04-17 15:15 ` Theodore Ts'o
2019-04-17 15:40 ` Kees Cook
2019-04-17 15:53 ` David Laight
2019-04-24 11:42 ` Reshetova, Elena
2019-04-24 13:33 ` David Laight
2019-04-25 11:23 ` Reshetova, Elena
2019-04-26 11:33 ` Reshetova, Elena
2019-04-26 14:01 ` Theodore Ts'o
2019-04-26 17:44 ` Eric Biggers
2019-04-26 18:02 ` Theodore Ts'o
2019-04-27 13:59 ` Andy Lutomirski
2019-04-29 8:04 ` Reshetova, Elena
2019-04-26 18:34 ` Andy Lutomirski
2019-04-29 7:46 ` Reshetova, Elena
2019-04-29 16:08 ` Andy Lutomirski
2019-04-30 17:51 ` Reshetova, Elena
2019-04-30 18:01 ` Kees Cook
2019-05-01 8:23 ` David Laight
2019-05-02 8:07 ` Reshetova, Elena
2019-05-01 8:41 ` David Laight
2019-05-01 23:33 ` Andy Lutomirski
2019-05-02 8:15 ` Reshetova, Elena
2019-05-02 9:23 ` David Laight
2019-05-02 14:47 ` Andy Lutomirski
2019-05-02 15:08 ` Ingo Molnar
2019-05-02 16:32 ` Andy Lutomirski
2019-05-02 16:43 ` Ingo Molnar
2019-05-03 16:40 ` Andy Lutomirski
2019-05-02 16:34 ` David Laight
2019-05-02 16:45 ` Ingo Molnar
2019-05-03 16:17 ` Reshetova, Elena
2019-05-03 16:40 ` David Laight
2019-05-03 19:10 ` Linus Torvalds
2019-05-06 6:47 ` Reshetova, Elena
2019-05-06 7:01 ` Reshetova, Elena
2019-05-08 11:18 ` Reshetova, Elena
2019-05-08 11:32 ` Ingo Molnar
2019-05-08 13:22 ` Reshetova, Elena
2019-05-09 5:59 ` Ingo Molnar
2019-05-09 7:01 ` Reshetova, Elena
2019-05-09 8:43 ` Ingo Molnar
2019-05-11 22:45 ` Andy Lutomirski
2019-05-12 0:12 ` Kees Cook
2019-05-12 8:02 ` Ingo Molnar
2019-05-12 14:33 ` Kees Cook
2019-05-28 12:28 ` Reshetova, Elena
2019-05-28 13:33 ` Theodore Ts'o
2019-05-29 10:13 ` Reshetova, Elena
2019-05-29 10:51 ` David Laight
2019-05-29 18:35 ` Kees Cook
2019-05-29 18:37 ` Kees Cook
2019-07-29 11:41 ` Reshetova, Elena
2019-07-30 18:07 ` Kees Cook
2019-08-01 6:35 ` Reshetova, Elena
2019-05-09 7:03 ` Reshetova, Elena
2019-05-06 7:32 ` Reshetova, Elena
2019-04-29 7:49 ` Reshetova, Elena
2019-04-26 17:37 ` Edgecombe, Rick P
2019-04-17 6:24 ` Ingo Molnar
2019-04-16 18:19 ` Reshetova, Elena
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