Unverified Commit 298ab06a authored by Christian Brauner's avatar Christian Brauner
Browse files

nstree: use guards for ns_tree_lock 

Make use of the guard infrastructure for ns_tree_lock.

Link: https://patch.msgid.link/20251110-work-namespace-nstree-fixes-v1-7-e8a9264e0fb9@kernel.org


Signed-off-by: default avatarChristian Brauner <brauner@kernel.org>
parent 8a30420c

kernel/nstree.c

+13 −7
Original line number Diff line number Diff line
@@ -10,6 +10,14 @@ 


static __cacheline_aligned_in_smp DEFINE_SEQLOCK(ns_tree_lock);



DEFINE_LOCK_GUARD_0(ns_tree_writer,

		    write_seqlock(&ns_tree_lock),

		    write_sequnlock(&ns_tree_lock))



DEFINE_LOCK_GUARD_0(ns_tree_locked_reader,

		    read_seqlock_excl(&ns_tree_lock),

		    read_sequnlock_excl(&ns_tree_lock))



static struct ns_tree_root ns_unified_root = { /* protected by ns_tree_lock */

	.ns_rb = RB_ROOT,

	.ns_list_head = LIST_HEAD_INIT(ns_unified_root.ns_list_head),
@@ -193,7 +201,7 @@ void __ns_tree_add_raw(struct ns_common *ns, struct ns_tree_root *ns_tree) 


	VFS_WARN_ON_ONCE(!ns->ns_id);



	write_seqlock(&ns_tree_lock);

	guard(ns_tree_writer)();



	/* Add to per-type tree and list */

	node = ns_tree_node_add(&ns->ns_tree_node, ns_tree, ns_cmp);
@@ -218,7 +226,6 @@ void __ns_tree_add_raw(struct ns_common *ns, struct ns_tree_root *ns_tree) 
			VFS_WARN_ON_ONCE(ns != to_ns_common(&init_user_ns));

		}

	}

	write_sequnlock(&ns_tree_lock);



	VFS_WARN_ON_ONCE(node);

}
@@ -461,9 +468,9 @@ static struct ns_common *lookup_ns_owner_at(u64 ns_id, struct ns_common *owner) 


	VFS_WARN_ON_ONCE(owner->ns_type != CLONE_NEWUSER);



	read_seqlock_excl(&ns_tree_lock);

	node = owner->ns_owner_root.ns_rb.rb_node;

	guard(ns_tree_locked_reader)();



	node = owner->ns_owner_root.ns_rb.rb_node;

	while (node) {

		struct ns_common *ns;
@@ -480,7 +487,6 @@ static struct ns_common *lookup_ns_owner_at(u64 ns_id, struct ns_common *owner) 


	if (ret)

		ret = ns_get_unless_inactive(ret);

	read_sequnlock_excl(&ns_tree_lock);

	return ret;

}
@@ -648,7 +654,8 @@ static struct ns_common *lookup_ns_id_at(u64 ns_id, int ns_type) 
			return NULL;

	}



	read_seqlock_excl(&ns_tree_lock);

	guard(ns_tree_locked_reader)();



	if (ns_tree)

		node = ns_tree->ns_rb.rb_node;

	else
@@ -677,7 +684,6 @@ static struct ns_common *lookup_ns_id_at(u64 ns_id, int ns_type) 


	if (ret)

		ret = ns_get_unless_inactive(ret);

	read_sequnlock_excl(&ns_tree_lock);

	return ret;

}