2024-05-14 15:19:12

by Chun-Yi Lee

[permalink] [raw]
Subject: [PATCH v2] aoe: fix the potential use-after-free problem in more places

For fixing CVE-2023-6270, f98364e92662 ("aoe: fix the potential
use-after-free problem in aoecmd_cfg_pkts") makes tx() do dev_put()
instead of doing in aoecmd_cfg_pkts(). It avoids that the tx() runs
into use-after-free.

But Nicolai Stange found more places in aoe have potential use-after-free
problem with tx(). e.g. revalidate(), aoecmd_ata_rw(), resend(), probe()
and aoecmd_cfg_rsp(). Those functions also use aoenet_xmit() to push
packet to tx queue. So they should also use dev_hold() to increase the
refcnt of skb->dev.

This patch makes the above functions do dev_put() when the skb_clone()
returns NULL.

Link: https://nvd.nist.gov/vuln/detail/CVE-2023-6270
Fixes: f98364e92662 ("aoe: fix the potential use-after-free problem in aoecmd_cfg_pkts")
Reported-by: Nicolai Stange <[email protected]>
Signed-off-by: Chun-Yi Lee <[email protected]>
---

v2:
- Improve patch description
- Improved wording
- Add oneline summary of the commit f98364e92662
- Used curly brackets in the if-else blocks.

drivers/block/aoe/aoecmd.c | 13 ++++++++++++-
1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/drivers/block/aoe/aoecmd.c b/drivers/block/aoe/aoecmd.c
index cc9077b588d7..d1f4ddc57645 100644
--- a/drivers/block/aoe/aoecmd.c
+++ b/drivers/block/aoe/aoecmd.c
@@ -361,6 +361,7 @@ ata_rw_frameinit(struct frame *f)
}

ah->cmdstat = ATA_CMD_PIO_READ | writebit | extbit;
+ dev_hold(t->ifp->nd);
skb->dev = t->ifp->nd;
}

@@ -401,6 +402,8 @@ aoecmd_ata_rw(struct aoedev *d)
__skb_queue_head_init(&queue);
__skb_queue_tail(&queue, skb);
aoenet_xmit(&queue);
+ } else {
+ dev_put(f->t->ifp->nd);
}
return 1;
}
@@ -483,10 +486,13 @@ resend(struct aoedev *d, struct frame *f)
memcpy(h->dst, t->addr, sizeof h->dst);
memcpy(h->src, t->ifp->nd->dev_addr, sizeof h->src);

+ dev_hold(t->ifp->nd);
skb->dev = t->ifp->nd;
skb = skb_clone(skb, GFP_ATOMIC);
- if (skb == NULL)
+ if (skb == NULL) {
+ dev_put(t->ifp->nd);
return;
+ }
f->sent = ktime_get();
__skb_queue_head_init(&queue);
__skb_queue_tail(&queue, skb);
@@ -617,6 +623,8 @@ probe(struct aoetgt *t)
__skb_queue_head_init(&queue);
__skb_queue_tail(&queue, skb);
aoenet_xmit(&queue);
+ } else {
+ dev_put(f->t->ifp->nd);
}
}

@@ -1395,6 +1403,7 @@ aoecmd_ata_id(struct aoedev *d)
ah->cmdstat = ATA_CMD_ID_ATA;
ah->lba3 = 0xa0;

+ dev_hold(t->ifp->nd);
skb->dev = t->ifp->nd;

d->rttavg = RTTAVG_INIT;
@@ -1404,6 +1413,8 @@ aoecmd_ata_id(struct aoedev *d)
skb = skb_clone(skb, GFP_ATOMIC);
if (skb)
f->sent = ktime_get();
+ else
+ dev_put(t->ifp->nd);

return skb;
}
--
2.35.3



2024-05-14 15:35:46

by Markus Elfring

[permalink] [raw]
Subject: Re: [PATCH v2] aoe: fix the potential use-after-free problem in more places

I suggest to reconsider the version identification in this patch subject
once more.



> This patch makes the above functions do …

Do you stumble still on wording challenges for improved change descriptions
in your patches?
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/process/submitting-patches.rst?h=v6.9#n94


> ---
>
> v2:
> - Improve patch description

V3:
???

V4:
???

Would you like to include issue reporters in message recipient lists?

Regards,
Markus

2024-05-15 05:09:56

by joeyli

[permalink] [raw]
Subject: Re: [PATCH v2] aoe: fix the potential use-after-free problem in more places

Hi Markus,

On Tue, May 14, 2024 at 05:34:57PM +0200, Markus Elfring wrote:
> I suggest to reconsider the version identification in this patch subject
> once more.
>
>
> …
> > This patch makes the above functions do …
>
> Do you stumble still on wording challenges for improved change descriptions
> in your patches?
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/process/submitting-patches.rst?h=v6.9#n94
>
> …
> > ---
> >
> > v2:
> > - Improve patch description
>
> V3:
> ???
>
> V4:
> ???
>
> Would you like to include issue reporters in message recipient lists?
>
> Regards,
> Markus

I will wait more suggestion for code side and send new version.

Thanks a lot!
Joey Lee