linux-kernel - Re: [PATCH 5/4] update ksm userspace interfaces

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <20090403162217.GB13121@x200.localdomain>
Date:	Fri, 3 Apr 2009 09:22:17 -0700
From:	Chris Wright <chrisw@...hat.com>
To:	Gerd Hoffmann <kraxel@...hat.com>
Cc:	Izik Eidus <ieidus@...hat.com>, Chris Wright <chrisw@...hat.com>,
	Anthony Liguori <anthony@...emonkey.ws>,
	Andrea Arcangeli <aarcange@...hat.com>,
	linux-kernel@...r.kernel.org, kvm@...r.kernel.org,
	linux-mm@...ck.org, avi@...hat.com, riel@...hat.com,
	jeremy@...p.org, mtosatti@...hat.com, hugh@...itas.com,
	corbet@....net, yaniv@...hat.com, dmonakhov@...nvz.org
Subject: Re: [PATCH 5/4] update ksm userspace interfaces

* Gerd Hoffmann (kraxel@...hat.com) wrote:
> mmput() call was in ->release() callback, ->release() in turn never was
> called because the kernel didn't zap the mappings because of the
> reference ...

Don't have this issue.  That mmput() is not tied to zapping mappings,
rather zapping files.  IOW, I think you're saying exit_mmap() wasn't
running due to your get_task_mm() (quite understandable, you still hold
a ref), whereas this ref is tied to exit_files().

So do_exit would do:

	exit_mm
	  mmput <-- not dropped yet
	exit_files
	  ->release
	    mmput <-- dropped here

thanks,
-chris
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/