Hi What if someone changes it to a larger type later? I think that if this branch doesn't do any harm and if it protects us from memory errors introduced by future changes, we may let it be there.
But I found another bug when looking at this - the user may set tag size up to MAX_TAG_SIZE (that is 0x1a8) and that gets truncated when it is assigned in "bi->metadata_size = ic->tag_size". I need to limit MAX_TAG_SIZE to 255. Mikulas On Mon, 8 Sep 2025, Ivan Abramov wrote: > Since bi->metadata_size is an unsigned char, it's not practically > possible for it to be > PAGE_SIZE / 2. > > Thus, remove the corresponding if statement. > > Found by Linux Verification Center (linuxtesting.org) with SVACE. > > Signed-off-by: Ivan Abramov <[email protected]> > --- > drivers/md/dm-integrity.c | 5 ----- > 1 file changed, 5 deletions(-) > > diff --git a/drivers/md/dm-integrity.c b/drivers/md/dm-integrity.c > index efeee0a873c0..b7ad7a5adb56 100644 > --- a/drivers/md/dm-integrity.c > +++ b/drivers/md/dm-integrity.c > @@ -4752,11 +4752,6 @@ static int dm_integrity_ctr(struct dm_target *ti, > unsigned int argc, char **argv > ti->error = "The integrity profile is smaller than tag > size"; > goto bad; > } > - if ((unsigned long)bi->metadata_size > PAGE_SIZE / 2) { > - r = -EINVAL; > - ti->error = "Too big tuple size"; > - goto bad; > - } > ic->tuple_size = bi->metadata_size; > if (1 << bi->interval_exp != ic->sectors_per_block << > SECTOR_SHIFT) { > r = -EINVAL; > -- > 2.39.5 > >
