On 01/02/2016 09:03 PM, Stephan Mueller wrote: > Am Samstag, 2. Januar 2016, 15:41:34 schrieb Milan Broz: > > Hi Milan, > ... >>> Hi Herbert, >>> >>> this patch breaks userspace in cryptsetup... >>> >>> We use algif_skcipher in cryptsetup (for years, even before >>> there was Stephan's library) and with this patch applied >>> I see fail in ALG_SET_IV call (patch from your git). >> >> (Obviously this was because of failing accept() call here, not set_iv.) >> >>> I can fix it upstream, but for thousands of installations it will >>> be broken (for LUKS there is a fallback, cor TrueCrypt compatible devices >>> it will be unusable. Also people who configured kernel crypto API as >>> default backend will have non-working cryptsetup). >>> >>> Is it really thing for stable branch? >> >> Also how it is supposed to work for cipher_null, where there is no key? >> Why it should call set_key if it is noop? (and set key length 0 is not >> possible). >> >> (We are using cipher_null for testing and for offline re-encryption tool >> to create temporary "fake" header for not-yet encrypted device...) > > The change implies that any setkey or set IV operations (i.e. any operations > on the tfmfd) are done before the opfd(s) are created with one or more accept > calls. > > Thus, after a bind that returns the tfmfd, the setkey and setiv operations > shall be called. This is followed by accept. If you change the order of > invocations in your code, it should work. Hi, I already changed it in cryptsetup upstream this way. But I cannot change thousands of cryptsetup installations that are actively using that code. This is clear userspace breakage which should not happen this way. (Moreover it still doesn't work for cipher_null that has min/max key size 0.) Milan -- To unsubscribe from this list: send the line "unsubscribe linux-crypto" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
