From c4fd43793bdecb986bfc80e00c8792556c3f1c7f Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Thu, 14 Sep 2017 02:01:16 +0300 Subject: [PATCH] ALSA: hwdep: prevent a harmless shift wrapping bug The "info.index" variable represents a bit in hw->dsp_loaded which is an unsigned int. If it's higher than 31 we hit a shift wrapping bug. This seems harmless, but I wanted to silence the static checker warning. Signed-off-by: Dan Carpenter Signed-off-by: Takashi Iwai --- sound/core/hwdep.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/sound/core/hwdep.c b/sound/core/hwdep.c index a73baa1242be..8faae3d1455d 100644 --- a/sound/core/hwdep.c +++ b/sound/core/hwdep.c @@ -228,6 +228,8 @@ static int snd_hwdep_dsp_load(struct snd_hwdep *hw, memset(&info, 0, sizeof(info)); if (copy_from_user(&info, _info, sizeof(info))) return -EFAULT; + if (info.index >= 32) + return -EINVAL; /* check whether the dsp was already loaded */ if (hw->dsp_loaded & (1 << info.index)) return -EBUSY;