Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 059338aa authored by Al Viro's avatar Al Viro
Browse files

move mount_capable() calls to vfs_get_tree() 



sget_fc() is called only from ->get_tree() instances and
the only instance not calling it is legacy_get_tree(),
which calls mount_capable() directly.

In all sget_fc() callers the checks could be moved to the
very beginning of ->get_tree() - ->user_ns is not changed
in between.  So lifting the checks to the only caller of
->get_tree() is OK.

Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent d5f68d33

fs/fs_context.c

+0 −5
Original line number Diff line number Diff line
@@ -662,11 +662,6 @@ static int legacy_get_tree(struct fs_context *fc) 
	struct super_block *sb;

	struct dentry *root;



	if (!(fc->sb_flags & (SB_KERNMOUNT|SB_SUBMOUNT))) {

		if (!mount_capable(fc))

			return -EPERM;

	}



	root = fc->fs_type->mount(fc->fs_type, fc->sb_flags,

				      fc->source, ctx->legacy_data);

	if (IS_ERR(root))

fs/super.c

+6 −6
Original line number Diff line number Diff line
@@ -514,12 +514,6 @@ struct super_block *sget_fc(struct fs_context *fc, 
	struct user_namespace *user_ns = fc->global ? &init_user_ns : fc->user_ns;

	int err;



	if (!(fc->sb_flags & SB_KERNMOUNT) &&

	    fc->purpose != FS_CONTEXT_FOR_SUBMOUNT) {

		if (!mount_capable(fc))

			return ERR_PTR(-EPERM);

	}



retry:

	spin_lock(&sb_lock);

	if (test) {
@@ -1421,6 +1415,12 @@ int vfs_get_tree(struct fs_context *fc) 
	if (fc->root)

		return -EBUSY;



	if (!(fc->sb_flags & SB_KERNMOUNT) &&

	    fc->purpose != FS_CONTEXT_FOR_SUBMOUNT) {

		if (!mount_capable(fc))

			return -EPERM;

	}



	/* Get the mountable root in fc->root, with a ref on the root and a ref

	 * on the superblock.

	 */