2019-11-05 20:29:30

by Colin King

[permalink] [raw]
Subject: [PATCH] iio: temperature: ltc2983: fix u32 read into a unsigned long long

From: Colin Ian King <[email protected]>

Currently the read of temp using of_property_read_u32_index is reading
a u32 value into a unsigned long long. This relies on machine endianness
to work correctly, so fix this by reading a u32 value and setting temp
to this value.

Addresses-Coverity: ("Reliance on integer endianness")
Fixes: f110f3188e56 ("iio: temperature: Add support for LTC2983")
Signed-off-by: Colin Ian King <[email protected]>
---
drivers/iio/temperature/ltc2983.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/iio/temperature/ltc2983.c b/drivers/iio/temperature/ltc2983.c
index ddf47023364b..d39c0d6b77f1 100644
--- a/drivers/iio/temperature/ltc2983.c
+++ b/drivers/iio/temperature/ltc2983.c
@@ -444,8 +444,10 @@ static struct ltc2983_custom_sensor *__ltc2983_custom_sensor_new(
else
temp = __convert_to_raw(temp, resolution);
} else {
- of_property_read_u32_index(np, propname, index,
- (u32 *)&temp);
+ u32 t32;
+
+ of_property_read_u32_index(np, propname, index, &t32);
+ temp = t32;
}

for (j = 0; j < n_size; j++)
--
2.20.1


2019-11-06 14:23:56

by Nuno Sa

[permalink] [raw]
Subject: Re: [PATCH] iio: temperature: ltc2983: fix u32 read into a unsigned long long

On Tue, 2019-11-05 at 20:28 +0000, Colin King wrote:
>
> From: Colin Ian King <[email protected]>
>
> Currently the read of temp using of_property_read_u32_index is
> reading
> a u32 value into a unsigned long long. This relies on machine
> endianness
> to work correctly, so fix this by reading a u32 value and setting
> temp
> to this value.
>
> Addresses-Coverity: ("Reliance on integer endianness")
> Fixes: f110f3188e56 ("iio: temperature: Add support for LTC2983")
> Signed-off-by: Colin Ian King <[email protected]>
> ---
> drivers/iio/temperature/ltc2983.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/iio/temperature/ltc2983.c
> b/drivers/iio/temperature/ltc2983.c
> index ddf47023364b..d39c0d6b77f1 100644
> --- a/drivers/iio/temperature/ltc2983.c
> +++ b/drivers/iio/temperature/ltc2983.c
> @@ -444,8 +444,10 @@ static struct ltc2983_custom_sensor
> *__ltc2983_custom_sensor_new(
> else
> temp = __convert_to_raw(temp,
> resolution);
> } else {
> - of_property_read_u32_index(np, propname, index,
> - (u32 *)&temp);
> + u32 t32;
> +
> + of_property_read_u32_index(np, propname, index,
> &t32);
> + temp = t32;
> }
>
> for (j = 0; j < n_size; j++)

Acked-by: Nuno Sá <[email protected]>

Thanks,
Nuno Sá

2019-11-10 11:49:25

by Jonathan Cameron

[permalink] [raw]
Subject: Re: [PATCH] iio: temperature: ltc2983: fix u32 read into a unsigned long long

On Wed, 6 Nov 2019 14:19:52 +0000
"Sa, Nuno" <[email protected]> wrote:

> On Tue, 2019-11-05 at 20:28 +0000, Colin King wrote:
> >
> > From: Colin Ian King <[email protected]>
> >
> > Currently the read of temp using of_property_read_u32_index is
> > reading
> > a u32 value into a unsigned long long. This relies on machine
> > endianness
> > to work correctly, so fix this by reading a u32 value and setting
> > temp
> > to this value.
> >
> > Addresses-Coverity: ("Reliance on integer endianness")
> > Fixes: f110f3188e56 ("iio: temperature: Add support for LTC2983")
> > Signed-off-by: Colin Ian King <[email protected]>
> > ---
> > drivers/iio/temperature/ltc2983.c | 6 ++++--
> > 1 file changed, 4 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/iio/temperature/ltc2983.c
> > b/drivers/iio/temperature/ltc2983.c
> > index ddf47023364b..d39c0d6b77f1 100644
> > --- a/drivers/iio/temperature/ltc2983.c
> > +++ b/drivers/iio/temperature/ltc2983.c
> > @@ -444,8 +444,10 @@ static struct ltc2983_custom_sensor
> > *__ltc2983_custom_sensor_new(
> > else
> > temp = __convert_to_raw(temp,
> > resolution);
> > } else {
> > - of_property_read_u32_index(np, propname, index,
> > - (u32 *)&temp);
> > + u32 t32;
> > +
> > + of_property_read_u32_index(np, propname, index,
> > &t32);
> > + temp = t32;
> > }
> >
> > for (j = 0; j < n_size; j++)
>
> Acked-by: Nuno Sá <[email protected]>
>

A slight complexity around this one. I'm not sure I'll have time for a pull
before the merge window (as Greg will only take them to about 1 week before
that opens so we get some exposure in Linux next).

As a result I'll have to sit on this one until Linus comments on rc7, probably
later today. Otherwise it'll be material for stable post release.

If I seem to have lost it give me a poke and we'll make sure it goes into
an early rc instead of at the merge window.

Thanks,

Jonathan

> Thanks,
> Nuno Sá

2019-11-16 15:19:22

by Jonathan Cameron

[permalink] [raw]
Subject: Re: [PATCH] iio: temperature: ltc2983: fix u32 read into a unsigned long long

On Sun, 10 Nov 2019 11:48:23 +0000
Jonathan Cameron <[email protected]> wrote:

> On Wed, 6 Nov 2019 14:19:52 +0000
> "Sa, Nuno" <[email protected]> wrote:
>
> > On Tue, 2019-11-05 at 20:28 +0000, Colin King wrote:
> > >
> > > From: Colin Ian King <[email protected]>
> > >
> > > Currently the read of temp using of_property_read_u32_index is
> > > reading
> > > a u32 value into a unsigned long long. This relies on machine
> > > endianness
> > > to work correctly, so fix this by reading a u32 value and setting
> > > temp
> > > to this value.
> > >
> > > Addresses-Coverity: ("Reliance on integer endianness")
> > > Fixes: f110f3188e56 ("iio: temperature: Add support for LTC2983")
> > > Signed-off-by: Colin Ian King <[email protected]>
> > > ---
> > > drivers/iio/temperature/ltc2983.c | 6 ++++--
> > > 1 file changed, 4 insertions(+), 2 deletions(-)
> > >
> > > diff --git a/drivers/iio/temperature/ltc2983.c
> > > b/drivers/iio/temperature/ltc2983.c
> > > index ddf47023364b..d39c0d6b77f1 100644
> > > --- a/drivers/iio/temperature/ltc2983.c
> > > +++ b/drivers/iio/temperature/ltc2983.c
> > > @@ -444,8 +444,10 @@ static struct ltc2983_custom_sensor
> > > *__ltc2983_custom_sensor_new(
> > > else
> > > temp = __convert_to_raw(temp,
> > > resolution);
> > > } else {
> > > - of_property_read_u32_index(np, propname, index,
> > > - (u32 *)&temp);
> > > + u32 t32;
> > > +
> > > + of_property_read_u32_index(np, propname, index,
> > > &t32);
> > > + temp = t32;
> > > }
> > >
> > > for (j = 0; j < n_size; j++)
> >
> > Acked-by: Nuno Sá <[email protected]>
> >
>
> A slight complexity around this one. I'm not sure I'll have time for a pull
> before the merge window (as Greg will only take them to about 1 week before
> that opens so we get some exposure in Linux next).
>
> As a result I'll have to sit on this one until Linus comments on rc7, probably
> later today. Otherwise it'll be material for stable post release.
>
> If I seem to have lost it give me a poke and we'll make sure it goes into
> an early rc instead of at the merge window.
I forgot about it when I sent the final pull request out. Sorry about that,
will have to wait for post merge window.

Applied to the fixes-togreg branch of iio.git.

Thanks,

Jonathan

>
> Thanks,
>
> Jonathan
>
> > Thanks,
> > Nuno Sá
>