Re: [PATCH v2] mfd: stmfx: Uninitialized variable in stmfx_irq_handler()

[Lee Jones <lee.jones@linaro.org>]

On Thu, 06 Jun 2019, Dan Carpenter wrote:

> The problem is that on 64bit systems then we don't clear the higher
> bits of the "pending" variable.  So when we do:
> 
>         ack = pending & ~BIT(STMFX_REG_IRQ_SRC_EN_GPIO);
>         if (ack) {
> 
> the if (ack) condition relies on uninitialized data.  The fix it that
> I've changed "pending" from an unsigned long to a u32.  I changed "n" as
> well, because that's a number in the 0-10 range and it fits easily
> inside an int.  We do need to add a cast to "pending" when we use it in
> the for_each_set_bit() loop, but that doesn't cause a proble, it's
> fine.
> 
> Fixes: 06252ade9156 ("mfd: Add ST Multi-Function eXpander (STMFX) core driver")
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> ---
> v2: white space changes
> 
>  drivers/mfd/stmfx.c | 10 ++++------
>  1 file changed, 4 insertions(+), 6 deletions(-)

Applied, thanks.

-- 
Lee Jones [李琼斯]
Linaro Services Technical Lead
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