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SubjectRe: [patch] udf: potential integer overflow
On Mon 15-03-10 11:21:13, Dan Carpenter wrote:
> bloc->logicalBlockNum is unsigned so it's never less than zero.
>
> When I saw that, it made me worry that "bloc->logicalBlockNum + count"
> could overflow. That's why I changed the check for less than zero
> to an overflow check. (The test works because "count" is also
> unsigned.)
>
> Signed-off-by: Dan Carpenter <error27@gmail.com>
Thanks. Merged.

> ---
> GCC 4.1 apparently optimizes overflow checks like this away, but it should
> work for other versions of gcc. I tested with GCC 4.3.
> http://www.fefe.de/intof.html
It should only optimize them out for signed types (moreover kernel has
this optimization turned off so it's a non-issue for us anyway).

Honza

--
Jan Kara <jack@suse.cz>
SUSE Labs, CR


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