ZVOLs should not be allowed to have children

[mirror_zfs.git] / module / zfs / dmu_recv.c

diff --git a/module/zfs/dmu_recv.c b/module/zfs/dmu_recv.c
index 990f790256be4dcb5333e8b674fa988e5981a80e..e05b5ad821f0ec81299a057babd16addd88a43a1 100644 (file)
--- a/module/zfs/dmu_recv.c
+++ b/module/zfs/dmu_recv.c
@@ -26,6 +26,7 @@
  * Copyright 2014 HybridCluster. All rights reserved.
  * Copyright 2016 RackTop Systems.
  * Copyright (c) 2016 Actifio, Inc. All rights reserved.
+ * Copyright (c) 2018, loli10K <ezomori.nozomu@gmail.com>. All rights reserved.
  */
 
 #include <sys/dmu.h>
@@ -79,6 +80,7 @@ recv_begin_check_existing_impl(dmu_recv_begin_arg_t *drba, dsl_dataset_t *ds,
     uint64_t fromguid, uint64_t featureflags)
 {
        uint64_t val;
+       uint64_t children;
        int error;
        dsl_pool_t *dp = ds->ds_dir->dd_pool;
        boolean_t encrypted = ds->ds_dir->dd_crypto_obj != 0;
@@ -99,6 +101,15 @@ recv_begin_check_existing_impl(dmu_recv_begin_arg_t *drba, dsl_dataset_t *ds,
        if (error != ENOENT)
                return (error == 0 ? EEXIST : error);
 
+       /* must not have children if receiving a ZVOL */
+       error = zap_count(dp->dp_meta_objset,
+           dsl_dir_phys(ds->ds_dir)->dd_child_dir_zapobj, &children);
+       if (error != 0)
+               return (error);
+       if (drba->drba_cookie->drc_drrb->drr_type != DMU_OST_ZFS &&
+           children > 0)
+               return (SET_ERROR(ZFS_ERR_WRONG_PARENT));
+
        /*
         * Check snapshot limit before receiving. We'll recheck again at the
         * end, but might as well abort before receiving if we're already over
@@ -283,6 +294,7 @@ dmu_recv_begin_check(void *arg, dmu_tx_t *tx)
        } else if (error == ENOENT) {
                /* target fs does not exist; must be a full backup or clone */
                char buf[ZFS_MAX_DATASET_NAME_LEN];
+               objset_t *os;
 
                /*
                 * If it's a non-clone incremental, we are missing the
@@ -352,6 +364,17 @@ dmu_recv_begin_check(void *arg, dmu_tx_t *tx)
                        return (error);
                }
 
+               /* can't recv below anything but filesystems (eg. no ZVOLs) */
+               error = dmu_objset_from_ds(ds, &os);
+               if (error != 0) {
+                       dsl_dataset_rele_flags(ds, dsflags, FTAG);
+                       return (error);
+               }
+               if (dmu_objset_type(os) != DMU_OST_ZFS) {
+                       dsl_dataset_rele_flags(ds, dsflags, FTAG);
+                       return (SET_ERROR(ZFS_ERR_WRONG_PARENT));
+               }
+
                if (drba->drba_origin != NULL) {
                        dsl_dataset_t *origin;
 
@@ -381,6 +404,7 @@ dmu_recv_begin_check(void *arg, dmu_tx_t *tx)
                        dsl_dataset_rele_flags(origin,
                            dsflags, FTAG);
                }
+
                dsl_dataset_rele_flags(ds, dsflags, FTAG);
                error = 0;
        }
@@ -1323,13 +1347,15 @@ receive_object(struct receive_writer_arg *rwa, struct drr_object *drro,
 
        if (data != NULL) {
                dmu_buf_t *db;
+               dnode_t *dn;
                uint32_t flags = DMU_READ_NO_PREFETCH;
 
                if (rwa->raw)
                        flags |= DMU_READ_NO_DECRYPT;
 
-               VERIFY0(dmu_bonus_hold_impl(rwa->os, drro->drr_object,
-                   FTAG, flags, &db));
+               VERIFY0(dnode_hold(rwa->os, drro->drr_object, FTAG, &dn));
+               VERIFY0(dmu_bonus_hold_by_dnode(dn, FTAG, &db, flags));
+
                dmu_buf_will_dirty(db, tx);
 
                ASSERT3U(db->db_size, >=, drro->drr_bonuslen);
@@ -1346,6 +1372,7 @@ receive_object(struct receive_writer_arg *rwa, struct drr_object *drro,
                            DRR_OBJECT_PAYLOAD_SIZE(drro));
                }
                dmu_buf_rele(db, FTAG);
+               dnode_rele(dn, FTAG);
        }
        dmu_tx_commit(tx);
 
@@ -1436,7 +1463,12 @@ receive_write(struct receive_writer_arg *rwa, struct drr_write *drrw,
        }
 
        VERIFY0(dnode_hold(rwa->os, drrw->drr_object, FTAG, &dn));
-       dmu_assign_arcbuf_by_dnode(dn, drrw->drr_offset, abuf, tx);
+       err = dmu_assign_arcbuf_by_dnode(dn, drrw->drr_offset, abuf, tx);
+       if (err != 0) {
+               dnode_rele(dn, FTAG);
+               dmu_tx_commit(tx);
+               return (err);
+       }
        dnode_rele(dn, FTAG);
 
        /*
@@ -1777,6 +1809,8 @@ receive_read_payload_and_next_header(struct receive_arg *ra, int len, void *buf)
                        ra->rrd->payload_size = len;
                        ra->rrd->bytes_read = ra->bytes_read;
                }
+       } else {
+               ASSERT3P(buf, ==, NULL);
        }
 
        ra->prev_cksum = ra->cksum;
@@ -1928,9 +1962,12 @@ receive_read_record(struct receive_arg *ra)
        {
                struct drr_object *drro = &ra->rrd->header.drr_u.drr_object;
                uint32_t size = DRR_OBJECT_PAYLOAD_SIZE(drro);
-               void *buf = kmem_zalloc(size, KM_SLEEP);
+               void *buf = NULL;
                dmu_object_info_t doi;
 
+               if (size != 0)
+                       buf = kmem_zalloc(size, KM_SLEEP);
+
                err = receive_read_payload_and_next_header(ra, size, buf);
                if (err != 0) {
                        kmem_free(buf, size);