On Wed, Apr 8, 2015 at 1:29 AM, Shengzhou.Liu@xxxxxxxxxxxxx <Shengzhou.Liu@xxxxxxxxxxxxx> wrote: >> On Tue, Apr 7, 2015 at 5:11 AM, Shengzhou Liu >> <Shengzhou.Liu@xxxxxxxxxxxxx> wrote: >> > In of_property_read_string function, strnlen(prop->value, >> > prop->length) is always less or equal to prop->length, and we should >> allow the '==' >> > condition, so let's remove the original unreasonable condition. >> >> I believe we don't want to allow equal because prop->length should >> include the \0 termination while strnlen will not. >> >> Rob > > Yes, I thought so, ideally prop->length should be assigned with strlen(value)+1, > but unfortunately in u-boot and kernel there are too many callers that have prop->length assigned > with strlen(value) instead of strlen(value)+1, in practice, we can allow equal. No one should touch prop->length and it comes from the DTB directly. It doesn't come from strlen. > For example, in of_property_read_string_helper function, following two lines had been removed by commit 6faa2909871d8937. I don't have that commit in my tree. > - if (strnlen(prop->value, prop->length) >= prop->length) > - return -EILSEQ; > > So allowing equal should be acceptable, because in this function, the equal can't prevent stack overflow issue. What stack overflow issue? Rob -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
