From: Bo YU <tsu.yubo@gmail.com>
To: Russell King - ARM Linux admin <linux@armlinux.org.uk>
Cc: l.stach@pengutronix.de,
"Christian Gmeiner" <christian.gmeiner@gmail.com>,
airlied@linux.ie, "Daniel Vetter" <daniel@ffwll.ch>,
etnaviv@lists.freedesktop.org, dri-devel@lists.freedesktop.org,
"open list" <linux-kernel@vger.kernel.org>, 于波 <yuzibode@126.com>
Subject: Re: [PATCH] drm: etnaviv: fix strncpy sizeof argument
Date: Tue, 19 Mar 2019 19:09:06 +0800 [thread overview]
Message-ID: <CAKq8=3JYGYWOnJYaQg5eguMjTo2c+dcCdj0WcKp+t4Oy=eYUFA@mail.gmail.com> (raw)
In-Reply-To: <20190319102216.ylrkd6vxm77pq553@shell.armlinux.org.uk>
On Tue, Mar 19, 2019 at 6:22 PM Russell King - ARM Linux admin
<linux@armlinux.org.uk> wrote:
>
> On Mon, Mar 18, 2019 at 10:57:55PM -0400, Bo YU wrote:
> > Calling strncpy with a maximum size argument of 64 bytes on destination
> > array "domain->name" of size 64 bytes might leave the destination string
> > unterminated.
> >
> > Detected by CoverityScan, CID# 1443992: Memory - illegal accesses
> > (BUFFER_SIZE_WARNING)
> >
> > Fixes: 9e2c2e2730126 (drm/etnaviv: add infrastructure to query perf counter)
> > Signed-off-by: Bo YU <tsu.yubo@gmail.com>
> > ---
> > drivers/gpu/drm/etnaviv/etnaviv_perfmon.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/gpu/drm/etnaviv/etnaviv_perfmon.c b/drivers/gpu/drm/etnaviv/etnaviv_perfmon.c
> > index 4227a4006c34..08ca3c44be48 100644
> > --- a/drivers/gpu/drm/etnaviv/etnaviv_perfmon.c
> > +++ b/drivers/gpu/drm/etnaviv/etnaviv_perfmon.c
> > @@ -414,7 +414,7 @@ int etnaviv_pm_query_dom(struct etnaviv_gpu *gpu,
> >
> > domain->id = domain->iter;
> > domain->nr_signals = dom->nr_signals;
> > - strncpy(domain->name, dom->name, sizeof(domain->name));
> > + strncpy(domain->name, dom->name, sizeof(dom->name));
>
> This introduces an overflow bug if sizeof(dom->name) >
> sizeof(domain->name). If both sizes are the same, then there is no
> effect.
Oops,It seems more worse than original code.
>
> strlcpy() would be a better replacement, it guarantees that the
> destination will be correctly terminated.
But there are too many strcpy like usage in kernel, Does it matter?
>
> --
> RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
> FTTC broadband for 0.8mile line in suburbia: sync at 12.1Mbps down 622kbps up
> According to speedtest.net: 11.9Mbps down 500kbps up
prev parent reply other threads:[~2019-03-19 11:09 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-03-19 2:57 [PATCH] drm: etnaviv: fix strncpy sizeof argument Bo YU
2019-03-19 10:22 ` Russell King - ARM Linux admin
2019-03-19 11:09 ` Bo YU [this message]
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='CAKq8=3JYGYWOnJYaQg5eguMjTo2c+dcCdj0WcKp+t4Oy=eYUFA@mail.gmail.com' \
--to=tsu.yubo@gmail.com \
--cc=airlied@linux.ie \
--cc=christian.gmeiner@gmail.com \
--cc=daniel@ffwll.ch \
--cc=dri-devel@lists.freedesktop.org \
--cc=etnaviv@lists.freedesktop.org \
--cc=l.stach@pengutronix.de \
--cc=linux-kernel@vger.kernel.org \
--cc=linux@armlinux.org.uk \
--cc=yuzibode@126.com \
/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).