FreeBSD: Fix ZFS so that snapshots under .zfs/snapshot are NFS visible

Call vfs_exjail_clone() for mounts created under .zfs/snapshot to fill in the mnt_exjail field for the mount. If this is not done, the snapshots under .zfs/snapshot with not be accessible over NFS. This version has the argument name in vfs.h fixed to match that of the name in spl_vfs.c, although it really does not matter. External-issue: https://reviews.freebsd.org/D42672 Reviewed-by: Alexander Motin <[email protected]> Signed-off-by: Rick Macklem <[email protected]> Closes #15563
openzfs · Nov 28, 2023 · acb33ee · acb33ee
1 parent c1a47de
commit acb33ee
Show file tree

Hide file tree

Showing 3 changed files with 11 additions and 3 deletions.
diff --git a/include/os/freebsd/spl/sys/vfs.h b/include/os/freebsd/spl/sys/vfs.h
@@ -101,7 +101,7 @@ void vfs_setmntopt(vfs_t *vfsp, const char *name, const char *arg,
 void vfs_clearmntopt(vfs_t *vfsp, const char *name);
 int vfs_optionisset(const vfs_t *vfsp, const char *opt, char **argp);
 int mount_snapshot(kthread_t *td, vnode_t **vpp, const char *fstype,
-    char *fspath, char *fspec, int fsflags);
+    char *fspath, char *fspec, int fsflags, vfs_t *parent_vfsp);
 
 typedef	uint64_t	vfs_feature_t;
 

diff --git a/module/os/freebsd/spl/spl_vfs.c b/module/os/freebsd/spl/spl_vfs.c
@@ -117,7 +117,7 @@ vfs_optionisset(const vfs_t *vfsp, const char *opt, char **argp)
 
 int
 mount_snapshot(kthread_t *td, vnode_t **vpp, const char *fstype, char *fspath,
-    char *fspec, int fsflags)
+    char *fspec, int fsflags, vfs_t *parent_vfsp)
 {
 	struct vfsconf *vfsp;
 	struct mount *mp;
@@ -217,6 +217,13 @@ mount_snapshot(kthread_t *td, vnode_t **vpp, const char *fstype, char *fspath,
 	mp->mnt_opt = mp->mnt_optnew;
 	(void) VFS_STATFS(mp, &mp->mnt_stat);
 
+#ifdef VFS_SUPPORTS_EXJAIL_CLONE
+	/*
+	 * Clone the mnt_exjail credentials of the parent, as required.
+	 */
+	vfs_exjail_clone(parent_vfsp, mp);
+#endif
+
 	/*
 	 * Prevent external consumers of mount options from reading
 	 * mnt_optnew.

diff --git a/module/os/freebsd/zfs/zfs_ctldir.c b/module/os/freebsd/zfs/zfs_ctldir.c
@@ -1026,7 +1026,8 @@ zfsctl_snapdir_lookup(struct vop_lookup_args *ap)
 	    "%s/" ZFS_CTLDIR_NAME "/snapshot/%s",
 	    dvp->v_vfsp->mnt_stat.f_mntonname, name);
 
-	err = mount_snapshot(curthread, vpp, "zfs", mountpoint, fullname, 0);
+	err = mount_snapshot(curthread, vpp, "zfs", mountpoint, fullname, 0,
+	    dvp->v_vfsp);
 	kmem_free(mountpoint, mountpoint_len);
 	if (err == 0) {
 		/*