From 84b0a4f4258420e1706d6ce6534c850cac251615 Mon Sep 17 00:00:00 2001 From: Changming Liu Date: Tue, 26 May 2020 00:39:21 +0000 Subject: [PATCH] ALSA: hwdep: fix a left shifting 1 by 31 UB bug [ Upstream commit fb8cd6481ffd126f35e9e146a0dcf0c4e8899f2e ] The "info.index" variable can be 31 in "1 << info.index". This might trigger an undefined behavior since 1 is signed. Fix this by casting 1 to 1u just to be sure "1u << 31" is defined. Signed-off-by: Changming Liu Cc: Link: https://lore.kernel.org/r/BL0PR06MB4548170B842CB055C9AF695DE5B00@BL0PR06MB4548.namprd06.prod.outlook.com Signed-off-by: Takashi Iwai Signed-off-by: Sasha Levin --- sound/core/hwdep.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/sound/core/hwdep.c b/sound/core/hwdep.c index 00cb5aed10a9..28bec15b0959 100644 --- a/sound/core/hwdep.c +++ b/sound/core/hwdep.c @@ -216,12 +216,12 @@ static int snd_hwdep_dsp_load(struct snd_hwdep *hw, if (info.index >= 32) return -EINVAL; /* check whether the dsp was already loaded */ - if (hw->dsp_loaded & (1 << info.index)) + if (hw->dsp_loaded & (1u << info.index)) return -EBUSY; err = hw->ops.dsp_load(hw, &info); if (err < 0) return err; - hw->dsp_loaded |= (1 << info.index); + hw->dsp_loaded |= (1u << info.index); return 0; }