From: Greg KH <gregkh@linuxfoundation.org>
To: Zhou Qingyang <zhou1615@umn.edu>
Cc: kjlu@umn.edu, Ben Skeggs <bskeggs@redhat.com>,
Karol Herbst <kherbst@redhat.com>, Lyude Paul <lyude@redhat.com>,
David Airlie <airlied@linux.ie>, Daniel Vetter <daniel@ffwll.ch>,
dri-devel@lists.freedesktop.org, nouveau@lists.freedesktop.org,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH] drm/nouveau/acr: Fix undefined behavior in nvkm_acr_hsfw_load_bl()
Date: Fri, 28 Jan 2022 11:18:04 +0100 [thread overview]
Message-ID: <YfPC3N+H9Fu/gqpz@kroah.com> (raw)
In-Reply-To: <20220124165856.57022-1-zhou1615@umn.edu>
On Tue, Jan 25, 2022 at 12:58:55AM +0800, Zhou Qingyang wrote:
> In nvkm_acr_hsfw_load_bl(), the return value of kmalloc() is directly
> passed to memcpy(), which could lead to undefined behavior on failure
> of kmalloc().
>
> Fix this bug by using kmemdup() instead of kmalloc()+memcpy().
>
> This bug was found by a static analyzer.
>
> Builds with 'make allyesconfig' show no new warnings,
> and our static analyzer no longer warns about this code.
>
> Fixes: 22dcda45a3d1 ("drm/nouveau/acr: implement new subdev to replace "secure boot"")
> Signed-off-by: Zhou Qingyang <zhou1615@umn.edu>
> ---
> The analysis employs differential checking to identify inconsistent
> security operations (e.g., checks or kfrees) between two code paths
> and confirms that the inconsistent operations are not recovered in the
> current function or the callers, so they constitute bugs.
>
> Note that, as a bug found by static analysis, it can be a false
> positive or hard to trigger. Multiple researchers have cross-reviewed
> the bug.
>
> drivers/gpu/drm/nouveau/nvkm/subdev/acr/hsfw.c | 9 +++++----
> 1 file changed, 5 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/acr/hsfw.c b/drivers/gpu/drm/nouveau/nvkm/subdev/acr/hsfw.c
> index 667fa016496e..a6ea89a5d51a 100644
> --- a/drivers/gpu/drm/nouveau/nvkm/subdev/acr/hsfw.c
> +++ b/drivers/gpu/drm/nouveau/nvkm/subdev/acr/hsfw.c
> @@ -142,11 +142,12 @@ nvkm_acr_hsfw_load_bl(struct nvkm_acr *acr, const char *name, int ver,
>
> hsfw->imem_size = desc->code_size;
> hsfw->imem_tag = desc->start_tag;
> - hsfw->imem = kmalloc(desc->code_size, GFP_KERNEL);
> - memcpy(hsfw->imem, data + desc->code_off, desc->code_size);
> -
> + hsfw->imem = kmemdup(data + desc->code_off, desc->code_size, GFP_KERNEL);
> nvkm_firmware_put(fw);
> - return 0;
> + if (!hsfw->imem)
> + return -ENOMEM;
> + else
> + return 0;
> }
>
> int
> --
> 2.25.1
>
As stated before, umn.edu is still not allowed to contribute to the
Linux kernel. Please work with your administration to resolve this
issue.
next prev parent reply other threads:[~2022-01-28 10:18 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-01-24 16:58 [PATCH] drm/nouveau/acr: Fix undefined behavior in nvkm_acr_hsfw_load_bl() Zhou Qingyang
2022-01-25 19:11 ` Lyude Paul
2022-01-28 10:18 ` Greg KH [this message]
2022-01-28 19:20 ` Lyude Paul
2022-01-28 19:53 ` Alex Deucher
2022-01-28 19:57 ` Lyude Paul
2022-01-29 8:32 ` Greg KH
2022-01-28 19:57 ` Karol Herbst
2022-01-28 20:01 ` Alex Deucher
2022-01-29 8:30 ` Greg KH
2022-01-29 14:18 ` Kangjie Lu
2022-01-29 14:47 ` Greg KH
2022-01-29 15:19 ` Kangjie Lu
2022-01-29 15:54 ` Greg KH
2022-01-29 8:24 ` Greg KH
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=YfPC3N+H9Fu/gqpz@kroah.com \
--to=gregkh@linuxfoundation.org \
--cc=airlied@linux.ie \
--cc=bskeggs@redhat.com \
--cc=daniel@ffwll.ch \
--cc=dri-devel@lists.freedesktop.org \
--cc=kherbst@redhat.com \
--cc=kjlu@umn.edu \
--cc=linux-kernel@vger.kernel.org \
--cc=lyude@redhat.com \
--cc=nouveau@lists.freedesktop.org \
--cc=zhou1615@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).