Hi Doug, On Wed, Aug 02, 2017 at 03:54:32PM -0700, Doug Anderson wrote: > Hi, > > On Fri, Jul 28, 2017 at 10:12 AM, Matthias Kaehlcke <[email protected]> wrote: > > comp_algorithm_store() passes the size of the source buffer to strlcpy() > > instead of the destination buffer size, fix this. > > This was introduced in commit 415403be37e2 ("zram: use crypto api to > check alg availability"), but probably don't need a "Fixes" since > there's not really a bug (see below) > > > Signed-off-by: Matthias Kaehlcke <[email protected]> > > --- > > drivers/block/zram/zram_drv.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c > > index 856d5dc02451..7d2ddffad361 100644 > > --- a/drivers/block/zram/zram_drv.c > > +++ b/drivers/block/zram/zram_drv.c > > @@ -327,7 +327,7 @@ static ssize_t comp_algorithm_store(struct device *dev, > > return -EBUSY; > > } > > > > - strlcpy(zram->compressor, compressor, sizeof(compressor)); > > + strlcpy(zram->compressor, compressor, sizeof(zram->compressor)); > > As far as I can tell the two sizes are identical. In struct zram: > > char compressor[CRYPTO_MAX_ALG_NAME]; > > Locally here: > > char compressor[CRYPTO_MAX_ALG_NAME]; > > ...so there is no bug per say unless there's a hidden "#undef". > ...but your change does make it a little clearer, plus if someone ever > changed one of these arrays it would be safer. Thus: > > Reviewed-by: Douglas Anderson <[email protected]> > > > I suppose another option would be to define the local array based on > the size of the structure. AKA locally in the function: > > char compressor[ARRAY_SIZE(zram->compressor)]; > > ...if you did that you could replace the strlcpy() below with a simple > strcpy() since you'd be guaranteed that there's be enough space. > ...but I'm probably overthinking it too much. ;-P
First of all, Thanks for the patch, Matthias. You are correct and you patch doesn't have any problem. However, I think Doug's suggestion looks better. Could you mind resending? Thanks.
