From 7b30ee6bafe91ebd3b34433ef3b943fd07a98cea Mon Sep 17 00:00:00 2001 From: Tom Caputi Date: Tue, 20 Feb 2018 12:41:07 -0500 Subject: [PATCH] Project dnode should be protected by local MAC This patch corrects a small security issue with 9c5167d1. When the project dnode was added to the objset_phys_t, it was not included in the local MAC for cryptographic protection, allowing an attacker to modify this data without the consent of the key holder. This patch does represent an on-disk format change for anyone using project dnodes on an encrypted dataset. Signed-off-by: Tom Caputi Signed-off-by: Brian Behlendorf Closes #7177 --- module/zfs/zio_crypt.c | 38 ++++++++++++++++++++++++++------------ 1 file changed, 26 insertions(+), 12 deletions(-) diff --git a/module/zfs/zio_crypt.c b/module/zfs/zio_crypt.c index 823e6b8d66..155bce9fb4 100644 --- a/module/zfs/zio_crypt.c +++ b/module/zfs/zio_crypt.c @@ -1095,9 +1095,9 @@ error: /* * objset_phys_t blocks introduce a number of exceptions to the normal - * authentication process. objset_phys_t's contain 2 seperate HMACS for + * authentication process. objset_phys_t's contain 2 separate HMACS for * protecting the integrity of their data. The portable_mac protects the - * the metadnode. This MAC can be sent with a raw send and protects against + * metadnode. This MAC can be sent with a raw send and protects against * reordering of data within the metadnode. The local_mac protects the user * accounting objects which are not sent from one system to another. * @@ -1199,8 +1199,10 @@ zio_crypt_do_objset_hmacs(zio_crypt_key_t *key, void *data, uint_t datalen, * The local MAC protects the user and group accounting. If these * objects are not present, the local MAC is zeroed out. */ - if (osp->os_userused_dnode.dn_type == DMU_OT_NONE && - osp->os_groupused_dnode.dn_type == DMU_OT_NONE) { + if (datalen >= OBJSET_PHYS_SIZE_V2 && + osp->os_userused_dnode.dn_type == DMU_OT_NONE && + osp->os_groupused_dnode.dn_type == DMU_OT_NONE && + osp->os_projectused_dnode.dn_type == DMU_OT_NONE) { bzero(local_mac, ZIO_OBJSET_MAC_LEN); return (0); } @@ -1231,15 +1233,27 @@ zio_crypt_do_objset_hmacs(zio_crypt_key_t *key, void *data, uint_t datalen, } /* add in fields from the user accounting dnodes */ - ret = zio_crypt_do_dnode_hmac_updates(ctx, key->zk_version, - should_bswap, &osp->os_userused_dnode); - if (ret) - goto error; + if (osp->os_userused_dnode.dn_type != DMU_OT_NONE) { + ret = zio_crypt_do_dnode_hmac_updates(ctx, key->zk_version, + should_bswap, &osp->os_userused_dnode); + if (ret) + goto error; + } - ret = zio_crypt_do_dnode_hmac_updates(ctx, key->zk_version, - should_bswap, &osp->os_groupused_dnode); - if (ret) - goto error; + if (osp->os_groupused_dnode.dn_type != DMU_OT_NONE) { + ret = zio_crypt_do_dnode_hmac_updates(ctx, key->zk_version, + should_bswap, &osp->os_groupused_dnode); + if (ret) + goto error; + } + + if (osp->os_projectused_dnode.dn_type != DMU_OT_NONE && + datalen >= OBJSET_PHYS_SIZE_V3) { + ret = zio_crypt_do_dnode_hmac_updates(ctx, key->zk_version, + should_bswap, &osp->os_projectused_dnode); + if (ret) + goto error; + } /* store the final digest in a temporary buffer and copy what we need */ cd.cd_length = SHA512_DIGEST_LENGTH;