On Fri, Jul 14, 2017 at 04:51:31PM -0700, Kees Cook wrote: > On Fri, Jul 14, 2017 at 2:28 PM, Daniel Micay <danielmicay@xxxxxxxxx> wrote: > > Using strscpy was wrong because FORTIFY_SOURCE is passing the maximum > > possible size of the outermost object, but strscpy defines the count > > parameter as the exact buffer size, so this could copy past the end of > > the source. This would still be wrong with the planned usage of > > __builtin_object_size(p, 1) for intra-object overflow checks since it's > > the maximum possible size of the specified object with no guarantee of > > it being that large. > > > > Reuse of the fortified functions like this currently makes the runtime > > error reporting less precise but that can be improved later on. > > > > Signed-off-by: Daniel Micay <danielmicay@xxxxxxxxx> > > Thanks for fixing this! Linus, do you want to take this directly or > have it go via -mm where fortify landed originally? > > Acked-by: Kees Cook <keescook@xxxxxxxxxxxx> > > As far as testing goes, was the NFS tree not in -next, or was a test > not running against -next? I'm curious why it took until the NFS tree > landed in Linus's tree for this to get noticed. Fortify was in -next > for a while... There was a last-minute rebase of that tree. I don't see anything relevant there. The code in question has been the same for ages. But I most be overlooking something.... I guess it could be interesting to bisect to figure out when the warning started. --b. -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
