From: Gao Xiang <gaoxiang25@huawei.com>
To: Eric Biggers <ebiggers@kernel.org>
Cc: Miao Xie <miaoxie@huawei.com>,
linux-erofs@lists.ozlabs.org, LKML <linux-kernel@vger.kernel.org>,
Lasse Collin <lasse.collin@tukaani.org>
Subject: Re: [PATCH 3/3] erofs: handle corrupted images whose decompressed size less than it'd be
Date: Wed, 26 Feb 2020 10:44:08 +0800 [thread overview]
Message-ID: <20200226024408.GB106025@architecture4> (raw)
In-Reply-To: <20200226024047.GA106025@architecture4>
On Wed, Feb 26, 2020 at 10:40:47AM +0800, Gao Xiang wrote:
> Hi Eric,
>
> On Tue, Feb 25, 2020 at 06:34:58PM -0800, Eric Biggers wrote:
> > On Wed, Feb 26, 2020 at 10:30:11AM +0800, Gao Xiang wrote:
> > > As Lasse pointed out, "Looking at fs/erofs/decompress.c,
> > > the return value from LZ4_decompress_safe_partial is only
> > > checked for negative value to catch errors. ... So if
> > > I understood it correctly, if there is bad data whose
> > > uncompressed size is much less than it should be, it can
> > > leave part of the output buffer untouched and expose the
> > > previous data as the file content. "
> > >
> > > Let's fix it now.
> > >
> > > Cc: Lasse Collin <lasse.collin@tukaani.org>
> > > Signed-off-by: Gao Xiang <gaoxiang25@huawei.com>
> >
> > Shouldn't fixes like this have a Fixes tag and Cc stable?
> >
> > - Eric
>
> Thanks for pointing out. *thumb up*
>
> I reminded Fixes and Cc tags when I sent out. Yet
> I'm not quite sure if these have some other potential
> concernes which could cause unexpected behavior for
> normal images (It seems impossible but not quite sure.)
>
> I'd like to leave these two commits for corrupted images
> to mainline and our products for a while and manually
> backport to stable kernels and send them to stable
> mailing list later. I keep these fixes in mind all
> the time.
... Maybe I should add "Fixes:" tag in the commit message
anyway. Will resend them later.
Thanks,
Gao Xiang
>
> Thanks,
> Gao Xiang
>
next prev parent reply other threads:[~2020-02-26 2:47 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-02-26 2:30 [PATCH 1/3] erofs: correct the remaining shrink objects Gao Xiang
2020-02-26 2:30 ` [PATCH 2/3] erofs: use LZ4_decompress_safe() for full decoding Gao Xiang
2020-03-03 9:49 ` Chao Yu
2020-02-26 2:30 ` [PATCH 3/3] erofs: handle corrupted images whose decompressed size less than it'd be Gao Xiang
2020-02-26 2:34 ` Eric Biggers
2020-02-26 2:40 ` Gao Xiang
2020-02-26 2:44 ` Gao Xiang [this message]
2020-03-03 9:51 ` Chao Yu
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=20200226024408.GB106025@architecture4 \
--to=gaoxiang25@huawei.com \
--cc=ebiggers@kernel.org \
--cc=lasse.collin@tukaani.org \
--cc=linux-erofs@lists.ozlabs.org \
--cc=linux-kernel@vger.kernel.org \
--cc=miaoxie@huawei.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).