mfd: stmfx: Uninitialized variable in stmfx_irq_handler()
authorDan Carpenter <dan.carpenter@oracle.com>
Thu, 6 Jun 2019 12:41:27 +0000 (15:41 +0300)
committerLee Jones <lee.jones@linaro.org>
Mon, 17 Jun 2019 09:51:15 +0000 (10:51 +0100)
commitcd49b84d61b2dfc0360c76d9e6be49f5116ba1a5
tree9b8f387c39bca7c7c5f01111b03f58f7a5c8cea1
parenta188339ca5a396acc588e5851ed7e19f66b0ebd9
mfd: stmfx: Uninitialized variable in stmfx_irq_handler()

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 problem, it's
fine.

Fixes: 06252ade9156 ("mfd: Add ST Multi-Function eXpander (STMFX) core driver")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Amelie Delaunay <amelie.delaunay@st.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
drivers/mfd/stmfx.c