From: Navid Emamdoost <navid.emamdoost@gmail.com>
To: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Leon Romanovsky <leon@kernel.org>,
Navid Emamdoost <emamd001@umn.edu>,
Stephen McCamant <smccaman@umn.edu>, Kangjie Lu <kjlu@umn.edu>,
Potnuri Bharat Teja <bharat@chelsio.com>,
Doug Ledford <dledford@redhat.com>,
linux-rdma@vger.kernel.org, LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v2] RDMA: release allocated skb
Date: Wed, 2 Oct 2019 16:35:06 -0500 [thread overview]
Message-ID: <CAEkB2EQF0D-Fdg74+E4VdxipZvTaBKseCtKJKnFg7T6ZZE9x6Q@mail.gmail.com> (raw)
In-Reply-To: <20191001135430.GA27086@ziepe.ca>
Hi Jason,
Thanks for the feedback. Yes, you are right if the skb release is
moved under err4 label it will cause a double free as
c4iw_ref_send_wait will release skb in case of error.
So, in order to avoid leaking skb in case of c4iw_bar2_addrs failure,
the kfree(skb) could be placed under the error check like the way
patch v1 did. Do you see any mistake in version 1?
https://lore.kernel.org/patchwork/patch/1128510/
Thanks,
Navid
On Tue, Oct 1, 2019 at 8:54 AM Jason Gunthorpe <jgg@ziepe.ca> wrote:
>
> On Mon, Sep 23, 2019 at 10:52:59AM -0500, Navid Emamdoost wrote:
> > In create_cq, the allocated skb buffer needs to be released on error
> > path.
> > Moved the kfree_skb(skb) under err4 label.
>
> This didn't move anything
>
> > Signed-off-by: Navid Emamdoost <navid.emamdoost@gmail.com>
> > drivers/infiniband/hw/cxgb4/cq.c | 1 +
> > 1 file changed, 1 insertion(+)
> >
> > diff --git a/drivers/infiniband/hw/cxgb4/cq.c b/drivers/infiniband/hw/cxgb4/cq.c
> > index b1bb61c65f4f..1886c1af10bc 100644
> > +++ b/drivers/infiniband/hw/cxgb4/cq.c
> > @@ -173,6 +173,7 @@ static int create_cq(struct c4iw_rdev *rdev, struct t4_cq *cq,
> > err4:
> > dma_free_coherent(&rdev->lldi.pdev->dev, cq->memsize, cq->queue,
> > dma_unmap_addr(cq, mapping));
> > + kfree_skb(skb);
> > err3:
> > kfree(cq->sw_queue);
> > err2:
>
> This looks wrong to me:
>
> int c4iw_ofld_send(struct c4iw_rdev *rdev, struct sk_buff *skb)
> {
> int error = 0;
>
> if (c4iw_fatal_error(rdev)) {
> kfree_skb(skb);
> pr_err("%s - device in error state - dropping\n", __func__);
> return -EIO;
> }
> error = cxgb4_ofld_send(rdev->lldi.ports[0], skb);
> if (error < 0)
> kfree_skb(skb);
> return error < 0 ? error : 0;
> }
>
> Jason
--
Navid.
next prev parent reply other threads:[~2019-10-02 21:35 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20190923050823.GL14368@unreal>
2019-09-23 15:52 ` [PATCH v2] RDMA: release allocated skb Navid Emamdoost
2019-10-01 13:54 ` Jason Gunthorpe
2019-10-02 21:35 ` Navid Emamdoost [this message]
2019-10-03 8:20 ` Leon Romanovsky
2019-10-03 10:25 ` Potnuri Bharat Teja
2019-10-04 18:12 ` Navid Emamdoost
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=CAEkB2EQF0D-Fdg74+E4VdxipZvTaBKseCtKJKnFg7T6ZZE9x6Q@mail.gmail.com \
--to=navid.emamdoost@gmail.com \
--cc=bharat@chelsio.com \
--cc=dledford@redhat.com \
--cc=emamd001@umn.edu \
--cc=jgg@ziepe.ca \
--cc=kjlu@umn.edu \
--cc=leon@kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-rdma@vger.kernel.org \
--cc=smccaman@umn.edu \
/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).