| Message ID | 20220128112007.GA24806@kili |
|---|---|
| State | New |
| Headers | show |
| Series | [1/2] ASoC: ops: fix signedness bug in snd_soc_put_volsw() | expand |
On Fri, Jan 28, 2022 at 12:42:04PM +0000, Mark Brown wrote: > On Fri, Jan 28, 2022 at 02:20:07PM +0300, Dan Carpenter wrote: > > The "val" and "val2" variables need to signed for the checking to work > > as intended. > > This means that the helpers won't support controls that use the top bit > of a 32 bit register. Fine, I can delete the checks for negative instead (I'm surprised you haven't already received a dozen bot emails about this). I haven't been able to figure out where mc->min/max are set. In snd_soc_get_xr_sx() it checks whether "mc->min" is negative. if (min < 0 && val > max) val |= ~mask; Is that a bug? If mc->min is negative the math gets tricky. regards, dan carpenter
On Fri, Jan 28, 2022 at 01:48:44PM +0000, Mark Brown wrote: > On Fri, Jan 28, 2022 at 04:31:47PM +0300, Dan Carpenter wrote: > > On Fri, Jan 28, 2022 at 12:42:04PM +0000, Mark Brown wrote: > > > > This means that the helpers won't support controls that use the top bit > > > of a 32 bit register. > > > Fine, I can delete the checks for negative instead (I'm surprised you > > haven't already received a dozen bot emails about this). > > No, we need the checks for negatives since userspace supplies a signed > value. The check needs to be done on the value in the input structure > before we pull it out for mangling. I probably got bot emails but > frankly these days almost all of them are some combination of barely > legible and misdirected and there's plenty of people who like to fix > these things if they're real. > That's a bit trickier than I initially imagined so I'm going to leave this for smarter people than me... regards, dan carpenter
diff --git a/sound/soc/soc-ops.c b/sound/soc/soc-ops.c index dc0e7c8d31f3..0091fa96eb48 100644 --- a/sound/soc/soc-ops.c +++ b/sound/soc/soc-ops.c @@ -310,8 +310,9 @@ int snd_soc_put_volsw(struct snd_kcontrol *kcontrol, unsigned int invert = mc->invert; int err; bool type_2r = false; - unsigned int val2 = 0; - unsigned int val, val_mask; + unsigned int val_mask; + int val2 = 0; + int val; if (sign_bit) mask = BIT(sign_bit + 1) - 1;
The "val" and "val2" variables need to signed for the checking to work as intended. Fixes: 817f7c9335ec ("ASoC: ops: Reject out of bounds values in snd_soc_put_volsw()") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> --- sound/soc/soc-ops.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)