On Fri, Aug 26, 2016 at 01:21:50PM -0500, Eric Blake wrote: > On 08/26/2016 07:47 AM, Daniel P. Berrange wrote: > > The XTS cipher mode needs to be used with a cipher which has > > a block size of 16 bytes. If a mis-matching block size is used, > > the code will either corrupt memory beyond the IV array, or > > not fully encrypt/decrypt the IV. > > > > This fixes a memory curruption crash when attempting to use > > s/curruption/corruption/ > > > cast5-128 with xts, since the former has an 8 byte block size. > > > > A test case is added to ensure the cipher creation fails with > > such an invalid combination. > > > > Signed-off-by: Daniel P. Berrange <berra...@redhat.com> > > --- > > crypto/cipher-gcrypt.c | 6 ++++++ > > crypto/cipher-nettle.c | 12 +++++++----- > > tests/test-crypto-cipher.c | 44 > > ++++++++++++++++++++++++++++++++++++-------- > > 3 files changed, 49 insertions(+), 13 deletions(-) > > Are you aiming for a last-minute 2.7 fix, or should this just be 2.8 > material and cc qemu-stable?
This isn't critical for 2.7, as this is already invalid usage. IOW anyone who hits the crash, simply shouldn't use this combination. > Reviewed-by: Eric Blake <ebl...@redhat.com> > > > > +++ b/tests/test-crypto-cipher.c > > @@ -370,6 +370,17 @@ static QCryptoCipherTestData test_data[] = { > > > @@ -449,8 +468,16 @@ static void test_cipher(const void *opaque) > > cipher = qcrypto_cipher_new( > > data->alg, data->mode, > > key, nkey, > > - &error_abort); > > - g_assert(cipher != NULL); > > + &err); > > + if (data->plaintext) { > > + g_assert(err == NULL); > > + g_assert(cipher != NULL); > > + } else { > > + g_assert(err != NULL); > > + error_free(err); > > Could shorten these two lines as error_free_or_abort(&err), but that's > cosmetic. Will do. Regards, Daniel -- |: http://berrange.com -o- http://www.flickr.com/photos/dberrange/ :| |: http://libvirt.org -o- http://virt-manager.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: http://entangle-photo.org -o- http://live.gnome.org/gtk-vnc :|