mtd: fix Coverity integer handling issue

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A Coverity robot reported an integer handling issue
(OVERFLOW_BEFORE_WIDEN) in the potentially overflowing expression:

    (mtd_div_by_ws(mtd->size, mtd) - mtd_div_by_ws(offs, mtd)) *
    mtd_oobavail(mtd, ops)

While such overflow will certainly never happen due to the numbers
handled, it is cleaner to fix this operation anyway.

The problem is that all the maths include 32-bit quantities, while the
result is stored in an explicit 64-bit value.

As maxooblen will just be compared with a size_t, let's change the
type of the variable to a size_t. This will not fix anything but will
clarify a bit the situation. Then, do an explicit cast to fix Coverity
warning.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>

...

This commit is contained in:

Miquel Raynal 2018-11-18 21:18:31 +01:00 • committed by Boris Brezillon

parent 4348433d8c

commit 89f706dbd5

1 changed files with 3 additions and 3 deletions

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drivers/mtd/mtdcore.c

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