From: Takashi Iwai tiwai@suse.de Sent: Tuesday, May 26, 2020 2:22 AM To: Changming Liu liu.changm@northeastern.edu Cc: perex@perex.cz; alsa-devel@alsa-project.org Subject: Re: [PATCH] ALSA: hwdep: fix a left shifting 1 by 31 UB bug
On Tue, 26 May 2020 02:39:21 +0200, Changming Liu wrote:
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
Thanks for the patch.
Unfortunately it seems that your MUA modified in quoted-printable and inapplicable with git-am as is. Since the changes are so small, I manually applied it now.
I see, thank you very much for pointing out this problem, I'll never use my MUA to send patch again. Also thank you for this manual modification.
Please fix the setup of your MUA at the next time, or better to try git-send-email to submit directly.
Sorry that I cannot configure my university email to work on git-send-email, I'll use my gmail to send patch via git next time.
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 b412d3b3d5ff..21edb8ac95eb 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;}
-- 2.17.1