Fix encryption hierarchy issues with zfs recv -d

Currently, the recv_fix_encryption_hierarchy() function accepts
'destsnap' as one of its parameters. Oriinally, this was intended
to be the top-level dataset of a receive (whether or not the
receive was recursive). Unfortunately, this parameter actually is
simply the input that is passed in from the command line. When
the user specifies 'zfs recv -d', this string is actually only the
name of the receiving pool since the rest of the name is derived
from the send stream. This causes the function to fail, leaving
some datasets with an invalid encryption hierarchy.

This patch resolves this problem by passing in the top_zfs variable
instead. In order to make this work, this patch also includes some
changes that ensure the value is always present when we need it.

Fixes: #9273

Signed-off-by: Tom Caputi <[email protected]>

include/libzfs.h

@@ -740,6 +740,9 @@ typedef struct recvflags {
 
 	/* skip receive of snapshot holds */
 	boolean_t skipholds;
+
+	/* mount the filesystem unless nomount is specified */
+	boolean_t domount;
 } recvflags_t;
 
 extern int zfs_receive(libzfs_handle_t *, const char *, nvlist_t *,

lib/libzfs/libzfs_sendrecv.c

@@ -3369,19 +3369,12 @@ created_before(libzfs_handle_t *hdl, avl_tree_t *avl,
  * sent datasets to their final locations in the dataset hierarchy.
  */
 static int
-recv_fix_encryption_hierarchy(libzfs_handle_t *hdl, const char *destname,
+recv_fix_encryption_hierarchy(libzfs_handle_t *hdl, const char *top_zfs,
     nvlist_t *stream_nv, avl_tree_t *stream_avl)
 {
 	int err;
 	nvpair_t *fselem = NULL;
 	nvlist_t *stream_fss;
-	char *cp;
-	char top_zfs[ZFS_MAX_DATASET_NAME_LEN];
-
-	(void) strcpy(top_zfs, destname);
-	cp = strrchr(top_zfs, '@');
-	if (cp != NULL)
-		*cp = '\0';
 
 	VERIFY(0 == nvlist_lookup_nvlist(stream_nv, "fss", &stream_fss));
 
@@ -3408,7 +3401,7 @@ recv_fix_encryption_hierarchy(libzfs_handle_t *hdl, const char *destname,
 			uint64_t guid;
 
 			VERIFY(0 == nvpair_value_uint64(snapel, &guid));
-			err = guid_to_name(hdl, destname, guid, B_FALSE,
+			err = guid_to_name(hdl, top_zfs, guid, B_FALSE,
 			    fsname);
 			if (err == 0)
 				break;
@@ -4009,8 +4002,8 @@ zfs_receive_package(libzfs_handle_t *hdl, int fd, const char *destname,
 		    stream_nv, stream_avl, NULL);
 	}
 
-	if (raw && softerr == 0) {
-		softerr = recv_fix_encryption_hierarchy(hdl, destname,
+	if (raw && softerr == 0 && *top_zfs != NULL) {
+		softerr = recv_fix_encryption_hierarchy(hdl, *top_zfs,
 		    stream_nv, stream_avl);
 	}
 
@@ -4845,8 +4838,17 @@ zfs_receive_one(libzfs_handle_t *hdl, int infd, const char *tosnap,
 		goto out;
 	}
 
-	if (top_zfs && (*top_zfs == NULL || strcmp(*top_zfs, name) == 0))
+	/*
+	 * If this is the top-level dataset, record it so we can use it
+	 * for recursive operations later.
+	 */
+	if (top_zfs != NULL &&
+	    (*top_zfs == NULL || strcmp(*top_zfs, name) == 0)) {
 		toplevel = B_TRUE;
+		if (*top_zfs == NULL)
+			*top_zfs = zfs_strdup(hdl, name);
+	}
+
 	if (drrb->drr_type == DMU_OST_ZVOL) {
 		type = ZFS_TYPE_VOLUME;
 	} else if (drrb->drr_type == DMU_OST_ZFS) {
@@ -4862,6 +4864,9 @@ zfs_receive_one(libzfs_handle_t *hdl, int infd, const char *tosnap,
 	    &oxprops, &wkeydata, &wkeylen, errbuf)) != 0)
 		goto out;
 
+	if ((newfs || stream_avl) && type == ZFS_TYPE_FILESYSTEM && !redacted)
+		flags->domount = B_TRUE;
+
 	/*
 	 * When sending with properties (zfs send -p), the encryption property
 	 * is not included because it is a SETONCE property and therefore
@@ -5100,29 +5105,6 @@ zfs_receive_one(libzfs_handle_t *hdl, int infd, const char *tosnap,
 	 * children of the target filesystem if we did a replication
 	 * receive (indicated by stream_avl being non-NULL).
 	 */
-	cp = strchr(destsnap, '@');
-	if (cp && (ioctl_err == 0 || !newfs) && !redacted) {
-		zfs_handle_t *h;
-
-		*cp = '\0';
-		h = zfs_open(hdl, destsnap,
-		    ZFS_TYPE_FILESYSTEM | ZFS_TYPE_VOLUME);
-		if (h != NULL) {
-			if (h->zfs_type == ZFS_TYPE_VOLUME) {
-				*cp = '@';
-			} else if (newfs || stream_avl) {
-				/*
-				 * Track the first/top of hierarchy fs,
-				 * for mounting and sharing later.
-				 */
-				if (top_zfs && *top_zfs == NULL)
-					*top_zfs = zfs_strdup(hdl, destsnap);
-			}
-			zfs_close(h);
-		}
-		*cp = '@';
-	}
-
 	if (clp) {
 		if (!flags->nomount)
 			err |= changelist_postfix(clp);
@@ -5427,24 +5409,38 @@ zfs_receive(libzfs_handle_t *hdl, const char *tosnap, nvlist_t *props,
 
 	VERIFY(0 == close(cleanup_fd));
 
-	if (err == 0 && !flags->nomount && top_zfs) {
+	if (err == 0 && !flags->nomount && flags->domount && top_zfs) {
 		zfs_handle_t *zhp = NULL;
 		prop_changelist_t *clp = NULL;
 
-		zhp = zfs_open(hdl, top_zfs, ZFS_TYPE_FILESYSTEM);
-		if (zhp != NULL) {
+		zhp = zfs_open(hdl, top_zfs,
+		    ZFS_TYPE_FILESYSTEM | ZFS_TYPE_VOLUME);
+		if (zhp == NULL) {
+			err = -1;
+			goto out;
+		} else {
+			if (zhp->zfs_type == ZFS_TYPE_VOLUME) {
+				zfs_close(zhp);
+				goto out;
+			}
+
 			clp = changelist_gather(zhp, ZFS_PROP_MOUNTPOINT,
 			    CL_GATHER_MOUNT_ALWAYS, 0);
 			zfs_close(zhp);
-			if (clp != NULL) {
-				/* mount and share received datasets */
-				err = changelist_postfix(clp);
-				changelist_free(clp);
+			if (clp == NULL) {
+				err = -1;
+				goto out;
 			}
+
+			/* mount and share received datasets */
+			err = changelist_postfix(clp);
+			changelist_free(clp);
+			if (err != 0)
+				err = -1;
 		}
-		if (zhp == NULL || clp == NULL || err)
-			err = -1;
 	}
+
+out:
 	if (top_zfs)
 		free(top_zfs);