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

Lee Jones
2019-06-03T08:12:04Z

On Wed, 15 May 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>
> ---
> drivers/mfd/stmfx.c | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)

Could do with an author's Ack here.

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