* Re: [PATCH] ALSA: pcm: prevent UAF in snd_pcm_info [not found] <20171205171657.74392-1-ndesaulniers@google.com> @ 2017-12-05 17:19 ` Nick Desaulniers 2017-12-05 17:26 ` Greg KH 0 siblings, 1 reply; 2+ messages in thread From: Nick Desaulniers @ 2017-12-05 17:19 UTC (permalink / raw) Cc: Kees Cook, Robb Glasser, Jaroslav Kysela, Takashi Iwai, Markus Elfring, Takashi Sakamoto, Arvind Yadav, alsa-devel, LKML, stable + stable On Tue, Dec 5, 2017 at 9:16 AM, Nick Desaulniers <ndesaulniers@google.com> wrote: > From: Robb Glasser <rglasser@google.com> > > When the device descriptor is closed, the `substream->runtime` pointer > is freed. But another thread may be in the ioctl handler, case > SNDRV_CTL_IOCTL_PCM_INFO. This case calls snd_pcm_info_user() which > calls snd_pcm_info() which accesses the now freed `substream->runtime`. > > Signed-off-by: Robb Glasser <rglasser@google.com> > Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> > --- > sound/core/pcm.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/sound/core/pcm.c b/sound/core/pcm.c > index 9070f277f8db..09ee8c6b9f75 100644 > --- a/sound/core/pcm.c > +++ b/sound/core/pcm.c > @@ -153,7 +153,9 @@ static int snd_pcm_control_ioctl(struct snd_card *card, > err = -ENXIO; > goto _error; > } > + mutex_lock(&pcm->open_mutex); > err = snd_pcm_info_user(substream, info); > + mutex_unlock(&pcm->open_mutex); > _error: > mutex_unlock(®ister_mutex); > return err; > -- > 2.15.0.531.g2ccb3012c9-goog > -- Thanks, ~Nick Desaulniers ^ permalink raw reply [flat|nested] 2+ messages in thread
* Re: [PATCH] ALSA: pcm: prevent UAF in snd_pcm_info 2017-12-05 17:19 ` [PATCH] ALSA: pcm: prevent UAF in snd_pcm_info Nick Desaulniers @ 2017-12-05 17:26 ` Greg KH 0 siblings, 0 replies; 2+ messages in thread From: Greg KH @ 2017-12-05 17:26 UTC (permalink / raw) To: Nick Desaulniers Cc: Kees Cook, Robb Glasser, Jaroslav Kysela, Takashi Iwai, Markus Elfring, Takashi Sakamoto, Arvind Yadav, alsa-devel, LKML, stable On Tue, Dec 05, 2017 at 09:19:32AM -0800, Nick Desaulniers wrote: > + stable > > On Tue, Dec 5, 2017 at 9:16 AM, Nick Desaulniers > <ndesaulniers@google.com> wrote: > > From: Robb Glasser <rglasser@google.com> > > > > When the device descriptor is closed, the `substream->runtime` pointer > > is freed. But another thread may be in the ioctl handler, case > > SNDRV_CTL_IOCTL_PCM_INFO. This case calls snd_pcm_info_user() which > > calls snd_pcm_info() which accesses the now freed `substream->runtime`. > > > > Signed-off-by: Robb Glasser <rglasser@google.com> > > Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> > > --- > > sound/core/pcm.c | 2 ++ > > 1 file changed, 2 insertions(+) <formletter> This is not the correct way to submit patches for inclusion in the stable kernel tree. Please read: https://www.kernel.org/doc/html/latest/process/stable-kernel-rules.html for how to do this properly. </formletter> ^ permalink raw reply [flat|nested] 2+ messages in thread
end of thread, other threads:[~2017-12-05 17:26 UTC | newest]
Thread overview: 2+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
[not found] <20171205171657.74392-1-ndesaulniers@google.com>
2017-12-05 17:19 ` [PATCH] ALSA: pcm: prevent UAF in snd_pcm_info Nick Desaulniers
2017-12-05 17:26 ` Greg KH
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).