Netdev Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Petko Manolov <petkan@nucleusys.com>
To: Pavel Skripkin <paskripkin@gmail.com>
Cc: davem@davemloft.net, kuba@kernel.org, linux-usb@vger.kernel.org,
	netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
	syzbot+02c9f70f3afae308464a@syzkaller.appspotmail.com
Subject: Re: [PATCH] net: pegasus: fix uninit-value in get_interrupt_interval
Date: Sun, 1 Aug 2021 23:24:21 +0300	[thread overview]
Message-ID: <YQcC9eOf5+MXZRsG@carbon> (raw)
In-Reply-To: <20210801223513.06bede26@gmail.com>

On 21-08-01 22:35:13, Pavel Skripkin wrote:
> On Sun, 1 Aug 2021 15:36:27 +0300 Petko Manolov <petkan@nucleusys.com> wrote:
> 
> > On 21-07-31 00:44:11, Pavel Skripkin wrote:
> > > Syzbot reported uninit value pegasus_probe(). The problem was in missing
> > > error handling.
> > > 
> > > get_interrupt_interval() internally calls read_eprom_word() which can fail
> > > in some cases. For example: failed to receive usb control message. These
> > > cases should be handled to prevent uninit value bug, since
> > > read_eprom_word() will not initialize passed stack variable in case of
> > > internal failure.
> > 
> > Well, this is most definitelly a bug.
> > 
> > ACK!
> > 
> > 
> >		Petko
> 
> BTW: I found a lot uses of {get,set}_registers without error checking. I
> think, some of them could be fixed easily (like in enable_eprom_write), but, I
> guess, disable_eprom_write is not so easy. For example, if we cannot disable
> eprom should we retry? If not, will device get in some unexpected state?

Everything bracketed by PEGASUS_WRITE_EEPROM is more or less dead code.  I've
added this feature because the chip give us the ability to write to the flash,
but i seriously doubt anybody ever used it.  Come to think about it, i should
just remove this code.

> Im not familiar with this device, but I can prepare a patch to wrap all these
> calls with proper error checking

Well, i've stared at the code a bit and i see some places where not checking the
error returned by {get,set}_registers() could really be problematic.  I'll cook
a patch with what i think needs doing and will submit it here for review.


cheers,
Petko

  reply	other threads:[~2021-08-01 20:24 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-07-30 21:44 Pavel Skripkin
2021-08-01 12:36 ` Petko Manolov
2021-08-01 19:35   ` Pavel Skripkin
2021-08-01 20:24     ` Petko Manolov [this message]
2021-08-02 20:07     ` Petko Manolov
2021-08-02 22:18       ` Pavel Skripkin
2021-08-03  5:36       ` Greg KH
2021-08-04 10:44 ` Pavel Skripkin
2021-08-04 11:58   ` Jakub Kicinski
2021-08-04 14:30     ` [PATCH net v2] " Pavel Skripkin
2021-08-05 14:50       ` patchwork-bot+netdevbpf

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=YQcC9eOf5+MXZRsG@carbon \
    --to=petkan@nucleusys.com \
    --cc=davem@davemloft.net \
    --cc=kuba@kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-usb@vger.kernel.org \
    --cc=netdev@vger.kernel.org \
    --cc=paskripkin@gmail.com \
    --cc=syzbot+02c9f70f3afae308464a@syzkaller.appspotmail.com \
    --subject='Re: [PATCH] net: pegasus: fix uninit-value in get_interrupt_interval' \
    /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

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).