linux-mm.kvack.org archive mirror
 help / color / mirror / Atom feed
From: Matthew Wilcox <willy@infradead.org>
To: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>,
	Kirill Tkhai <ktkhai@virtuozzo.com>,
	Dave Hansen <dave.hansen@linux.intel.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>, "H. Peter Anvin" <hpa@zytor.com>,
	Andrey Ryabinin <aryabinin@virtuozzo.com>,
	Alexander Potapenko <glider@google.com>,
	Andy Lutomirski <luto@kernel.org>, Borislav Petkov <bp@alien8.de>,
	Juergen Gross <jgross@suse.com>,
	"Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
	Kees Cook <keescook@chromium.org>,
	Mathias Krause <minipli@googlemail.com>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Kate Stewart <kstewart@linuxfoundation.org>,
	LKML <linux-kernel@vger.kernel.org>,
	kasan-dev <kasan-dev@googlegroups.com>,
	Linux-MM <linux-mm@kvack.org>
Subject: Re: [PATCH RFC] x86: KASAN: Sanitize unauthorized irq stack access
Date: Thu, 8 Feb 2018 11:00:18 -0800	[thread overview]
Message-ID: <20180208190016.GC9524@bombadil.infradead.org> (raw)
In-Reply-To: <20180208172026.6kqimndwyekyzzvl@treble>

On Thu, Feb 08, 2018 at 11:20:26AM -0600, Josh Poimboeuf wrote:
> The patch description is confusing.  It talks about "crappy drivers irq
> handlers when they access wrong memory on the stack".  But if I
> understand correctly, the patch doesn't actually protect against that
> case, because irq handlers run on the irq stack, and this patch only
> affects code which *isn't* running on the irq stack.

This would catch a crappy driver which allocates some memory on the
irq stack, squirrels the pointer to it away in a data structure, then
returns to process (or softirq) context and dereferences the pointer.

I have no idea if that's the case that Kirill is tracking down, but it's
something I can imagine someone doing.

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

  reply	other threads:[~2018-02-08 19:00 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-02-07 16:14 [PATCH RFC] x86: KASAN: Sanitize unauthorized irq stack access Kirill Tkhai
2018-02-07 18:38 ` Dave Hansen
2018-02-07 19:31   ` Dmitry Vyukov
2018-02-08 10:03   ` Kirill Tkhai
2018-02-08 16:30     ` Josh Poimboeuf
2018-02-08 16:41       ` Dmitry Vyukov
2018-02-08 17:20         ` Josh Poimboeuf
2018-02-08 19:00           ` Matthew Wilcox [this message]
2018-02-09  8:53             ` Kirill Tkhai

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20180208190016.GC9524@bombadil.infradead.org \
    --to=willy@infradead.org \
    --cc=aryabinin@virtuozzo.com \
    --cc=bp@alien8.de \
    --cc=dave.hansen@linux.intel.com \
    --cc=dvyukov@google.com \
    --cc=glider@google.com \
    --cc=gregkh@linuxfoundation.org \
    --cc=hpa@zytor.com \
    --cc=jgross@suse.com \
    --cc=jpoimboe@redhat.com \
    --cc=kasan-dev@googlegroups.com \
    --cc=keescook@chromium.org \
    --cc=kirill.shutemov@linux.intel.com \
    --cc=kstewart@linuxfoundation.org \
    --cc=ktkhai@virtuozzo.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=luto@kernel.org \
    --cc=mingo@redhat.com \
    --cc=minipli@googlemail.com \
    --cc=tglx@linutronix.de \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).