Re: [patch] udf: potential integer overflow

[Jan Kara]

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@xxxxxxxxx>
  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@xxxxxxx>
SUSE Labs, CR
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/