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From: Andrew Morton <akpm@linux-foundation.org>
To: drosenberg@vsecurity.com
Cc: chris@zankel.net, security@kernel.org,
	linux-kernel@vger.kernel.org, "Oleg Nesterov" <oleg@redhat.com>
Subject: Re: [Security] [PATCH] xtensa: prevent arbitrary read in ptrace
Date: Fri, 8 Jul 2011 11:42:38 -0700	[thread overview]
Message-ID: <20110708114238.d70315b7.akpm@linux-foundation.org> (raw)
In-Reply-To: <1652523982-1310150159-cardhu_decombobulator_blackberry.rim.net-183695056-@b1.c19.bise6.blackberry>

On Fri, 8 Jul 2011 18:35:56 +0000
"Dan Rosenberg" <drosenberg@vsecurity.com> wrote:

> Sorry for the top post and any email mangling (mobile).
> 
> I only used EIO to mirror the existing behavior in ptrace_getxregs(). EFAULT seems better.

ptrace_getxregs() is busted ;)


int ptrace_getxregs(struct task_struct *child, void __user *uregs)
{
...
	if (!access_ok(VERIFY_WRITE, uregs, sizeof(elf_xtregs_t)))
		return -EIO;
...
	ret |= __copy_to_user(&xtregs->user,&ti->xtregs_user,
			      sizeof(xtregs->user));

	return ret ? -EFAULT : 0;
}

that makes no sense.


  reply	other threads:[~2011-07-08 18:42 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-07-08 18:35 [Security] [PATCH] xtensa: prevent arbitrary read in ptrace Dan Rosenberg
2011-07-08 18:42 ` Andrew Morton [this message]
  -- strict thread matches above, loose matches on Subject: below --
2011-07-08  0:03 Dan Rosenberg
2011-07-08 18:27 ` [Security] " Andrew Morton
2011-07-08 18:42   ` Oleg Nesterov
2011-07-08 19:29     ` Chris Zankel

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