All of lore.kernel.org
 help / color / mirror / Atom feed
From: Bart Van Assche <Bart.VanAssche@sandisk.com>
To: "tj@kernel.org" <tj@kernel.org>, "jack@suse.cz" <jack@suse.cz>
Cc: "linux-block@vger.kernel.org" <linux-block@vger.kernel.org>,
	"hch@lst.de" <hch@lst.de>,
	"martin.petersen@oracle.com" <martin.petersen@oracle.com>,
	"linux-scsi@vger.kernel.org" <linux-scsi@vger.kernel.org>,
	"axboe@fb.com" <axboe@fb.com>,
	"scott.bauer@intel.com" <scott.bauer@intel.com>,
	"jejb@linux.vnet.ibm.com" <jejb@linux.vnet.ibm.com>,
	"jack@suse.com" <jack@suse.com>
Subject: Re: BUG: KASAN: use-after-free in scsi_exit_rq
Date: Tue, 2 May 2017 17:39:52 +0000	[thread overview]
Message-ID: <1493746791.2552.9.camel@sandisk.com> (raw)
In-Reply-To: <20170502144125.GK13916@quack2.suse.cz>

On Tue, 2017-05-02 at 16:41 +0200, Jan Kara wrote:
> So I'm also not aware of any particular breakage this would cause. Howeve=
r
> logically the freeing of request mempools really belongs to
> blk_release_queue() so it seems a bit dumb to move blk_exit_rl() just
> because SCSI stores the fact from which slab cache it has allocated the
> sense buffer in a structure (shost) that it frees under its hands by the
> time blk_release_queue() is called. :-|

Hello Jan,

My concern when I wrote my previous e-mail was that I didn't want to add a
scsi_host_get() / scsi_host_put() pair to the hot path in the SCSI core. Bu=
t
I just realized that scsi_init_rq() and scsi_exit_rq() are not in the hot
path so adding a scsi_host_get() / scsi_host_put() pair should work fine. I
will post a patch.

Bart.

WARNING: multiple messages have this Message-ID (diff)
From: Bart Van Assche <Bart.VanAssche@sandisk.com>
To: "tj@kernel.org" <tj@kernel.org>, "jack@suse.cz" <jack@suse.cz>
Cc: "linux-block@vger.kernel.org" <linux-block@vger.kernel.org>,
	"hch@lst.de" <hch@lst.de>,
	"martin.petersen@oracle.com" <martin.petersen@oracle.com>,
	"linux-scsi@vger.kernel.org" <linux-scsi@vger.kernel.org>,
	"axboe@fb.com" <axboe@fb.com>,
	"scott.bauer@intel.com" <scott.bauer@intel.com>,
	"jejb@linux.vnet.ibm.com" <jejb@linux.vnet.ibm.com>,
	"jack@suse.com" <jack@suse.com>
Subject: Re: BUG: KASAN: use-after-free in scsi_exit_rq
Date: Tue, 2 May 2017 17:39:52 +0000	[thread overview]
Message-ID: <1493746791.2552.9.camel@sandisk.com> (raw)
In-Reply-To: <20170502144125.GK13916@quack2.suse.cz>

On Tue, 2017-05-02 at 16:41 +0200, Jan Kara wrote:
> So I'm also not aware of any particular breakage this would cause. However
> logically the freeing of request mempools really belongs to
> blk_release_queue() so it seems a bit dumb to move blk_exit_rl() just
> because SCSI stores the fact from which slab cache it has allocated the
> sense buffer in a structure (shost) that it frees under its hands by the
> time blk_release_queue() is called. :-|

Hello Jan,

My concern when I wrote my previous e-mail was that I didn't want to add a
scsi_host_get() / scsi_host_put() pair to the hot path in the SCSI core. But
I just realized that scsi_init_rq() and scsi_exit_rq() are not in the hot
path so adding a scsi_host_get() / scsi_host_put() pair should work fine. I
will post a patch.

Bart.

  reply	other threads:[~2017-05-02 17:39 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-04-20 21:18 BUG: KASAN: use-after-free in scsi_exit_rq Scott Bauer
2017-04-21 21:49 ` Bart Van Assche
2017-04-21 21:49   ` Bart Van Assche
2017-04-28 21:46   ` tj
2017-05-02 14:41     ` Jan Kara
2017-05-02 17:39       ` Bart Van Assche [this message]
2017-05-02 17:39         ` Bart Van Assche

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=1493746791.2552.9.camel@sandisk.com \
    --to=bart.vanassche@sandisk.com \
    --cc=axboe@fb.com \
    --cc=hch@lst.de \
    --cc=jack@suse.com \
    --cc=jack@suse.cz \
    --cc=jejb@linux.vnet.ibm.com \
    --cc=linux-block@vger.kernel.org \
    --cc=linux-scsi@vger.kernel.org \
    --cc=martin.petersen@oracle.com \
    --cc=scott.bauer@intel.com \
    --cc=tj@kernel.org \
    /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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.