All of lore.kernel.org
 help / color / mirror / Atom feed
From: Stephen Lee <slee08177@gmail.com>
To: lgirdwood@gmail.com, broonie@kernel.org, perex@perex.cz, tiwai@suse.com
Cc: alsa-devel@alsa-project.org, linux-kernel@vger.kernel.org,
	linux-sound@vger.kernel.org, roman.gushchin@linux.dev,
	dennis@kernel.org, Stephen Lee <slee08177@gmail.com>
Subject: [PATCH] ASoC: ops: Fix wraparound for mask in snd_soc_get_volsw
Date: Mon, 25 Mar 2024 18:01:31 -0700	[thread overview]
Message-ID: <20240326010131.6211-1-slee08177@gmail.com> (raw)

In snd_soc_info_volsw(), mask is generated by figuring out the index of
the most significant bit set in max and converting the index to a
bitmask through bit shift 1. Unintended wraparound occurs when max is an
integer value with msb bit set. Since the bit shift value 1 is treated
as an integer type, the left shift operation will wraparound and set
mask to 0 instead of all 1's. In order to fix this, we type cast 1 as
`1ULL` to prevent the wraparound.

Fixes: 7077148fb50a ("ASoC: core: Split ops out of soc-core.c")
Signed-off-by: Stephen Lee <slee08177@gmail.com>
---

This seems to show up in quite a few places in the alsa subsystem,
should they be addressed altogether?

---
 sound/soc/soc-ops.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sound/soc/soc-ops.c b/sound/soc/soc-ops.c
index 2d25748ca706..b27e89ff6a16 100644
--- a/sound/soc/soc-ops.c
+++ b/sound/soc/soc-ops.c
@@ -263,7 +263,7 @@ int snd_soc_get_volsw(struct snd_kcontrol *kcontrol,
 	int max = mc->max;
 	int min = mc->min;
 	int sign_bit = mc->sign_bit;
-	unsigned int mask = (1 << fls(max)) - 1;
+	unsigned int mask = (1ULL << fls(max)) - 1;
 	unsigned int invert = mc->invert;
 	int val;
 	int ret;
-- 
2.43.2


             reply	other threads:[~2024-03-26  1:02 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-03-26  1:01 Stephen Lee [this message]
2024-03-28 19:28 ` [PATCH] ASoC: ops: Fix wraparound for mask in snd_soc_get_volsw Mark Brown
2024-03-29  1:29 ` Mark Brown

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20240326010131.6211-1-slee08177@gmail.com \
    --to=slee08177@gmail.com \
    --cc=alsa-devel@alsa-project.org \
    --cc=broonie@kernel.org \
    --cc=dennis@kernel.org \
    --cc=lgirdwood@gmail.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-sound@vger.kernel.org \
    --cc=perex@perex.cz \
    --cc=roman.gushchin@linux.dev \
    --cc=tiwai@suse.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.