From: Kees Cook <keescook@chromium.org>
To: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Alexey Romanov <avromanov@sberdevices.ru>,
linux-kernel@vger.kernel.org, Nick Terrell <terrelln@fb.com>,
Minchan Kim <minchan@kernel.org>,
Suleiman Souhlal <suleiman@google.com>,
Nitin Gupta <ngupta@vflare.org>, Jens Axboe <axboe@kernel.dk>,
Nhat Pham <nphamcs@gmail.com>,
Andrew Morton <akpm@linux-foundation.org>,
linux-block@vger.kernel.org,
"Gustavo A. R. Silva" <gustavo@embeddedor.com>,
linux-next@vger.kernel.org, linux-hardening@vger.kernel.org
Subject: Re: Coverity: zram_recompress(): OVERRUN
Date: Thu, 10 Nov 2022 19:15:05 -0800 [thread overview]
Message-ID: <202211101904.7A0B0C3@keescook> (raw)
In-Reply-To: <Y22WtxzDXM5PfFnb@google.com>
On Fri, Nov 11, 2022 at 09:26:31AM +0900, Sergey Senozhatsky wrote:
> On (22/11/10 08:47), coverity-bot wrote:
> > *** CID 1527270: (OVERRUN)
> > drivers/block/zram/zram_drv.c:1727 in zram_recompress()
> > 1721 zstrm = zcomp_stream_get(zram->comps[prio]);
> > 1722 src = kmap_atomic(page);
> > 1723 ret = zcomp_compress(zstrm, src, &comp_len_new);
> > 1724 kunmap_atomic(src);
> > 1725
> > 1726 if (ret) {
> > vvv CID 1527270: (OVERRUN)
> > vvv Overrunning array "zram->comps" of 4 8-byte elements at element index 4 (byte offset 39) using index "prio" (which evaluates to 4).
>
> Hmm... I don't really see how prio can evaluate to 4.
Yeah, I agree. This looks like a false positive. I'm not sure why
Coverity triggered for it. Looking at the extended report, it seems to
not have any idea that prio_max is correctly bounded.
Sorry for the noise!
--
Kees Cook
next prev parent reply other threads:[~2022-11-11 3:15 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-11-10 16:47 Coverity: zram_recompress(): OVERRUN coverity-bot
2022-11-11 0:26 ` Sergey Senozhatsky
2022-11-11 3:15 ` Kees Cook [this message]
2022-11-11 10:39 ` Sergey Senozhatsky
2022-11-11 0:37 ` Sergey Senozhatsky
2022-11-11 0:42 ` Sergey Senozhatsky
2022-11-11 3:16 ` Kees Cook
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=202211101904.7A0B0C3@keescook \
--to=keescook@chromium.org \
--cc=akpm@linux-foundation.org \
--cc=avromanov@sberdevices.ru \
--cc=axboe@kernel.dk \
--cc=gustavo@embeddedor.com \
--cc=linux-block@vger.kernel.org \
--cc=linux-hardening@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-next@vger.kernel.org \
--cc=minchan@kernel.org \
--cc=ngupta@vflare.org \
--cc=nphamcs@gmail.com \
--cc=senozhatsky@chromium.org \
--cc=suleiman@google.com \
--cc=terrelln@fb.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