android/android_kernel_asus_sm8350
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

ALSA: pcm: oss: Limit the period size to 16MB

Browse Source 
commit 8839c8c0f77ab8fc0463f4ab8b37fca3f70677c2 upstream.

Set the practical limit to the period size (the fragment shift in OSS)
instead of a full 31bit; a too large value could lead to the exhaust
of memory as we allocate temporary buffers of the period size, too.

As of this patch, we set to 16MB limit, which should cover all use
cases.

Reported-by: syzbot+bb348e9f9a954d42746f@syzkaller.appspotmail.com
Reported-by: Bixuan Cui <cuibixuan@linux.alibaba.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/1638270978-42412-1-git-send-email-cuibixuan@linux.alibaba.com
Link: https://lore.kernel.org/r/20211201073606.11660-3-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Takashi Iwai 2021-12-01 08:36:05 +01:00 committed by Greg Kroah-Hartman
parent f12c8a7515
commit 76f19e4cbb
1 changed files with 1 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
sound/core/oss/pcm_oss.c
View File

@ -1952,7 +1952,7 @@ static int snd_pcm_oss_set_fragment1(struct snd_pcm_substream *substream, unsign
if (runtime->oss.subdivision || runtime->oss.fragshift)
return -EINVAL;
fragshift = val & 0xffff;
if (fragshift >= 31)
if (fragshift >= 25) /* should be large enough */
return -EINVAL;
runtime->oss.fragshift = fragshift;
runtime->oss.maxfrags = (val >> 16) & 0xffff;