MFC r259168:

Don't even try to read vdev labels from devices smaller then SPA_MINDEVSIZE
(64MB).  Even if we would find one somehow, ZFS kernel code rejects such
devices.  It is funny to look on attempts to read 4 256K vdev labels from
1.44MB floppy, though it is not very practical and quite slow.

2 files changed, 17 insertions, 4 deletions

diff --git a/cddl/contrib/opensolaris/lib/libzfs/common/libzfs_import.c b/cddl/contrib/opensolaris/lib/libzfs/common/libzfs_import.c
index fa3d609..f683adb 100644
--- a/cddl/contrib/opensolaris/lib/libzfs/common/libzfs_import.c
+++ b/cddl/contrib/opensolaris/lib/libzfs/common/libzfs_import.c
@@ -995,10 +995,10 @@ nozpool_all_slices(avl_tree_t *r, const char *sname)
 #endif	/* sun */
 }
 
+#ifdef sun
 static void
 check_slices(avl_tree_t *r, int fd, const char *sname)
 {
-#ifdef sun
 	struct extvtoc vtoc;
 	struct dk_gpt *gpt;
 	char diskname[MAXNAMELEN];
@@ -1028,8 +1028,8 @@ check_slices(avl_tree_t *r, int fd, const char *sname)
 			check_one_slice(r, diskname, i, 0, 1);
 		efi_free(gpt);
 	}
-#endif	/* sun */
 }
+#endif	/* sun */
 
 static void
 zpool_open_func(void *arg)
@@ -1059,6 +1059,7 @@ zpool_open_func(void *arg)
 		return;
 	}
 	/* this file is too small to hold a zpool */
+#ifdef sun
 	if (S_ISREG(statbuf.st_mode) &&
 	    statbuf.st_size < SPA_MINDEVSIZE) {
 		(void) close(fd);
@@ -1070,6 +1071,12 @@ zpool_open_func(void *arg)
 		 */
 		check_slices(rn->rn_avl, fd, rn->rn_name);
 	}
+#else	/* !sun */
+	if (statbuf.st_size < SPA_MINDEVSIZE) {
+		(void) close(fd);
+		return;
+	}
+#endif	/* sun */
 
 	if ((zpool_read_label(fd, &config)) != 0) {
 		(void) close(fd);
diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/vdev_geom.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/vdev_geom.c
index 15685a5..72401d2 100644
--- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/vdev_geom.c
+++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/vdev_geom.c
@@ -370,10 +370,16 @@ vdev_geom_attach_taster(struct g_consumer *cp, struct g_provider *pp)
 
 	if (pp->flags & G_PF_WITHER)
 		return (EINVAL);
-	if (pp->sectorsize > VDEV_PAD_SIZE || !ISP2(pp->sectorsize))
-		return (EINVAL);
 	g_attach(cp, pp);
 	error = g_access(cp, 1, 0, 0);
+	if (error == 0) {
+		if (pp->sectorsize > VDEV_PAD_SIZE || !ISP2(pp->sectorsize))
+			error = EINVAL;
+		else if (pp->mediasize < SPA_MINDEVSIZE)
+			error = EINVAL;
+		if (error != 0)
+			g_access(cp, -1, 0, 0);
+	}
 	if (error != 0)
 		g_detach(cp);
 	return (error);