diff options
| -rw-r--r-- | fs/overlayfs/export.c | 26 | ||||
| -rw-r--r-- | fs/overlayfs/inode.c | 2 | ||||
| -rw-r--r-- | fs/overlayfs/overlayfs.h | 1 | ||||
| -rw-r--r-- | fs/overlayfs/ovl_entry.h | 1 | ||||
| -rw-r--r-- | fs/overlayfs/super.c | 9 |
5 files changed, 32 insertions, 7 deletions
diff --git a/fs/overlayfs/export.c b/fs/overlayfs/export.c index 35680b6e175b..6d54f3fc24c5 100644 --- a/fs/overlayfs/export.c +++ b/fs/overlayfs/export.c @@ -174,28 +174,37 @@ static int ovl_connect_layer(struct dentry *dentry) * U = upper file handle * L = lower file handle * - * (*) Connecting an overlay dir from real lower dentry is not always + * (*) Decoding a connected overlay dir from real lower dentry is not always * possible when there are redirects in lower layers and non-indexed merge dirs. * To mitigate those case, we may copy up the lower dir ancestor before encode - * a lower dir file handle. + * of a decodable file handle for non-upper dir. * * Return 0 for upper file handle, > 0 for lower file handle or < 0 on error. */ static int ovl_check_encode_origin(struct dentry *dentry) { struct ovl_fs *ofs = dentry->d_sb->s_fs_info; + bool decodable = ofs->config.nfs_export; + + /* Lower file handle for non-upper non-decodable */ + if (!ovl_dentry_upper(dentry) && !decodable) + return 0; /* Upper file handle for pure upper */ if (!ovl_dentry_lower(dentry)) return 0; /* - * Upper file handle for non-indexed upper. - * * Root is never indexed, so if there's an upper layer, encode upper for * root. */ - if (ovl_dentry_upper(dentry) && + if (dentry == dentry->d_sb->s_root) + return 0; + + /* + * Upper decodable file handle for non-indexed upper. + */ + if (ovl_dentry_upper(dentry) && decodable && !ovl_test_flag(OVL_INDEX, d_inode(dentry))) return 0; @@ -205,7 +214,7 @@ static int ovl_check_encode_origin(struct dentry *dentry) * ovl_connect_layer() will try to make origin's layer "connected" by * copying up a "connectable" ancestor. */ - if (d_is_dir(dentry) && ovl_upper_mnt(ofs)) + if (d_is_dir(dentry) && ovl_upper_mnt(ofs) && decodable) return ovl_connect_layer(dentry); /* Lower file handle for indexed and non-upper dir/non-dir */ @@ -876,3 +885,8 @@ const struct export_operations ovl_export_operations = { .get_name = ovl_get_name, .get_parent = ovl_get_parent, }; + +/* encode_fh() encodes non-decodable file handles with nfs_export=off */ +const struct export_operations ovl_export_fid_operations = { + .encode_fh = ovl_encode_fh, +}; diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c index a63e57447be9..c1c9ff62caad 100644 --- a/fs/overlayfs/inode.c +++ b/fs/overlayfs/inode.c @@ -1311,7 +1311,7 @@ static bool ovl_hash_bylower(struct super_block *sb, struct dentry *upper, return false; /* No, if non-indexed upper with NFS export */ - if (sb->s_export_op && upper) + if (ofs->config.nfs_export && upper) return false; /* Otherwise, hash by lower inode for fsnotify */ diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h index 488bd14c2ed8..453610fb9bf9 100644 --- a/fs/overlayfs/overlayfs.h +++ b/fs/overlayfs/overlayfs.h @@ -799,6 +799,7 @@ int ovl_set_origin(struct ovl_fs *ofs, struct dentry *lower, /* export.c */ extern const struct export_operations ovl_export_operations; +extern const struct export_operations ovl_export_fid_operations; /* super.c */ int ovl_fill_super(struct super_block *sb, struct fs_context *fc); diff --git a/fs/overlayfs/ovl_entry.h b/fs/overlayfs/ovl_entry.h index e999c73fb0c3..7a5196c94d75 100644 --- a/fs/overlayfs/ovl_entry.h +++ b/fs/overlayfs/ovl_entry.h @@ -82,6 +82,7 @@ struct ovl_fs { const struct cred *creator_cred; bool tmpfile; bool noxattr; + bool nofh; /* Did we take the inuse lock? */ bool upperdir_locked; bool workdir_locked; diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c index 9ed21f335adf..e56108ffe8aa 100644 --- a/fs/overlayfs/super.c +++ b/fs/overlayfs/super.c @@ -400,6 +400,7 @@ static int ovl_lower_dir(const char *name, struct path *path, pr_warn("fs on '%s' does not support file handles, falling back to index=off,nfs_export=off.\n", name); } + ofs->nofh |= !fh_type; /* * Decoding origin file handle is required for persistent st_ino. * Without persistent st_ino, xino=auto falls back to xino=off. @@ -818,6 +819,7 @@ static int ovl_make_workdir(struct super_block *sb, struct ovl_fs *ofs, ofs->config.index = false; pr_warn("upper fs does not support file handles, falling back to index=off.\n"); } + ofs->nofh |= !fh_type; /* Check if upper fs has 32bit inode numbers */ if (fh_type != FILEID_INO32_GEN) @@ -1452,8 +1454,15 @@ int ovl_fill_super(struct super_block *sb, struct fs_context *fc) ofs->config.nfs_export = false; } + /* + * Support encoding decodable file handles with nfs_export=on + * and encoding non-decodable file handles with nfs_export=off + * if all layers support file handles. + */ if (ofs->config.nfs_export) sb->s_export_op = &ovl_export_operations; + else if (!ofs->nofh) + sb->s_export_op = &ovl_export_fid_operations; /* Never override disk quota limits or use reserved space */ cap_lower(cred->cap_effective, CAP_SYS_RESOURCE); |