diff options
| -rw-r--r-- | fs/overlayfs/super.c | 59 |
1 files changed, 35 insertions, 24 deletions
diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c index bc8729491362..c1abd66527ce 100644 --- a/fs/overlayfs/super.c +++ b/fs/overlayfs/super.c @@ -827,6 +827,39 @@ static const struct xattr_handler *ovl_xattr_handlers[] = { NULL }; +static int ovl_get_upperpath(struct ovl_fs *ufs, struct path *upperpath) +{ + int err; + + err = ovl_mount_dir(ufs->config.upperdir, upperpath); + if (err) + goto out; + + /* Upper fs should not be r/o */ + if (sb_rdonly(upperpath->mnt->mnt_sb)) { + pr_err("overlayfs: upper fs is r/o, try multi-lower layers mount\n"); + err = -EINVAL; + goto out; + } + + err = ovl_check_namelen(upperpath, ufs, ufs->config.upperdir); + if (err) + goto out; + + err = -EBUSY; + if (ovl_inuse_trylock(upperpath->dentry)) { + ufs->upperdir_locked = true; + } else if (ufs->config.index) { + pr_err("overlayfs: upperdir is in-use by another mount, mount with '-o index=off' to override exclusive upperdir protection.\n"); + goto out; + } else { + pr_warn("overlayfs: upperdir is in-use by another mount, accessing files from both mounts will result in undefined behavior.\n"); + } + err = 0; +out: + return err; +} + static int ovl_fill_super(struct super_block *sb, void *data, int silent) { struct path upperpath = { }; @@ -870,30 +903,9 @@ static int ovl_fill_super(struct super_block *sb, void *data, int silent) goto out_free_config; } - err = ovl_mount_dir(ufs->config.upperdir, &upperpath); + err = ovl_get_upperpath(ufs, &upperpath); if (err) - goto out_free_config; - - /* Upper fs should not be r/o */ - if (sb_rdonly(upperpath.mnt->mnt_sb)) { - pr_err("overlayfs: upper fs is r/o, try multi-lower layers mount\n"); - err = -EINVAL; - goto out_put_upperpath; - } - - err = ovl_check_namelen(&upperpath, ufs, ufs->config.upperdir); - if (err) - goto out_put_upperpath; - - err = -EBUSY; - if (ovl_inuse_trylock(upperpath.dentry)) { - ufs->upperdir_locked = true; - } else if (ufs->config.index) { - pr_err("overlayfs: upperdir is in-use by another mount, mount with '-o index=off' to override exclusive upperdir protection.\n"); - goto out_put_upperpath; - } else { - pr_warn("overlayfs: upperdir is in-use by another mount, accessing files from both mounts will result in undefined behavior.\n"); - } + goto out_unlock_upperdentry; err = ovl_mount_dir(ufs->config.workdir, &workpath); if (err) @@ -1196,7 +1208,6 @@ out_put_workpath: out_unlock_upperdentry: if (ufs->upperdir_locked) ovl_inuse_unlock(upperpath.dentry); -out_put_upperpath: path_put(&upperpath); out_free_config: kfree(ufs->config.lowerdir); |