qemu-devel.nongnu.org archive mirror
 help / color / mirror / Atom feed
From: "Volker Rümelin" <vr_qemu@t-online.de>
To: Gerd Hoffmann <kraxel@redhat.com>
Cc: QEMU <qemu-devel@nongnu.org>, "Zoltán Kővágó" <dirty.ice.hu@gmail.com>
Subject: [PATCH] ossaudio: fix out of bounds write
Date: Tue,  7 Jul 2020 20:08:36 +0200	[thread overview]
Message-ID: <20200707180836.5435-1-vr_qemu@t-online.de> (raw)

In function oss_read() a read error currently does not exit the
read loop. With no data to read the variable pos will quickly
underflow and a subsequent successful read overwrites memory
outside the buffer. This patch adds the missing break statement
to the error path of the function.

To reproduce start qemu with -audiodev oss,id=audio0 and in the
guest start audio recording. After some time this will trigger
an exception.

Fixes: 3ba4066d08 "ossaudio: port to the new audio backend api"

Signed-off-by: Volker Rümelin <vr_qemu@t-online.de>
---
 audio/ossaudio.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/audio/ossaudio.c b/audio/ossaudio.c
index f88d076ec2..a7dcaa31ad 100644
--- a/audio/ossaudio.c
+++ b/audio/ossaudio.c
@@ -691,6 +691,7 @@ static size_t oss_read(HWVoiceIn *hw, void *buf, size_t len)
                            len, dst);
                 break;
             }
+            break;
         }
 
         pos += nread;
-- 
2.26.2



             reply	other threads:[~2020-07-07 18:09 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-07-07 18:08 Volker Rümelin [this message]
2020-07-08  8:30 ` [PATCH] ossaudio: fix out of bounds write Philippe Mathieu-Daudé
2020-07-08 20:09   ` Volker Rümelin
2020-07-09  1:08   ` BALATON Zoltan
2020-07-09 12:55   ` Gerd Hoffmann

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=20200707180836.5435-1-vr_qemu@t-online.de \
    --to=vr_qemu@t-online.de \
    --cc=dirty.ice.hu@gmail.com \
    --cc=kraxel@redhat.com \
    --cc=qemu-devel@nongnu.org \
    /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).