Commit fb8cd648 authored May 26, 2020 by Changming Liu Committed by Takashi Iwai May 26, 2020

ALSA: hwdep: fix a left shifting 1 by 31 UB bug



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 <liu.changm@northeastern.edu>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/BL0PR06MB4548170B842CB055C9AF695DE5B00@BL0PR06MB4548.namprd06.prod.outlook.com


Signed-off-by: Takashi Iwai <tiwai@suse.de>

parent 259eb824

sound/core/hwdep.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -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;
		}

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