----- Original Message ----- > From: "Herbert Xu" <herbert@xxxxxxxxxxxxxxxxxxx> > To: "Marcelo Cerri" <marcelo.cerri@xxxxxxxxxxxxx> > Cc: "Jan Stancek" <jstancek@xxxxxxxxxx>, "rui y wang" <rui.y.wang@xxxxxxxxx>, mhcerri@xxxxxxxxxxxxxxxxxx, > leosilva@xxxxxxxxxxxxxxxxxx, pfsmorigo@xxxxxxxxxxxxxxxxxx, linux-crypto@xxxxxxxxxxxxxxx, > linuxppc-dev@xxxxxxxxxxxxxxxx, linux-kernel@xxxxxxxxxxxxxxx > Sent: Wednesday, 28 September, 2016 4:45:49 AM > Subject: Re: [bug] crypto/vmx/p8_ghash memory corruption in 4.8-rc7 > > On Tue, Sep 27, 2016 at 04:46:44PM -0300, Marcelo Cerri wrote: > > > > Can you check if the problem occurs with this patch? > > In light of the fact that padlock-sha is the correct example > to follow, you only need to add one line to the init_tfm fucntion > to update the descsize based on that of the fallback. Thanks for clearing up how this works in padlock-sha, but we are not exactly in same situation with p8_ghash. p8_ghash_init_tfm() already updates descsize. Problem in original report is that without custom export/import/statesize p8_ghash_alg.statesize gets initialized by shash_prepare_alg() to alg->descsize: crash> p p8_ghash_alg.statesize $1 = 56 testmgr allocates space for export based on crypto_shash_statesize(), but shash_default_export() writes based on crypto_shash_descsize(): [ 8.297902] state: c0000004b873aa80, statesize: 56 [ 8.297932] shash_default_export memcpy c0000004b873aa80 c0000004b8607da0, len: 76 so I think we need either: 1) make sure p8_ghash_alg.descsize is correct before we register shash, this is what Marcelo's last patch is doing 2) provide custom export/import/statesize for p8_ghash_alg Regards, Jan > > Thanks, > -- > Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx> > Home Page: http://gondor.apana.org.au/~herbert/ > PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt > -- 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
