From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D4B0081745; Thu, 8 Aug 2024 18:02:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723140169; cv=none; b=EwiIwnR57f/ufpUdAANRG79GcoMZyW4AqOr8XravEkwx9Hb/SzOWtS/mqXvz3t3LRxVuROYkrnQDiTTgHoE/z2Ar/V5Ud7l4cqxOdRQma/sKpu7M93MKjQSbbyZE1smvkq6S9LW93bOrl/VPhKUMfJ9F10WeSwH/IMNyWo7gmT0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723140169; c=relaxed/simple; bh=7YdN0oj7fQwrSTsXIU36WQOIKQ7pRxhyimICcVHzHMI=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=lxS2ymcreqTJTT2uNozXksZHIlyOiJLi9oHfNjYhhdmqcejNgQ5+MLhXUoy90K7zYm7WrbJ+XnzXSruUztvQlEhHeDN0zPQKNCxsWg8WCkXdvoF6lyGJxKa1HU+ye+UKgcBD21DQwE6lh6fvoihSNXE0S+7iuusUW+/X4sXVf7o= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=NlbnyHCz; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="NlbnyHCz" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 56F6CC32782; Thu, 8 Aug 2024 18:02:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1723140169; bh=7YdN0oj7fQwrSTsXIU36WQOIKQ7pRxhyimICcVHzHMI=; h=Date:From:To:Cc:Subject:Reply-To:References:In-Reply-To:From; b=NlbnyHCzse9Yz4Y6qPy0UC+BhAzlPwVj8/cL9tfHHPluf7Vyo7zfo0YGnLhaj/Rsr dY8SSbvqmp04dj5b/Hp+jfqaIcaHIhTMjE+3M8+uQDLCq4dHr6uwO+dDnO5xvZumiv xZne0cd/nc9ixiA7Zfc0HLM+85khr1hNduLAkeh1xJmh58loFCWeJF/6BNz6SMU5dv 3KndT+1XonQrQmb1rbeqbS8GpginvupzSmrfmfBccSKn5hnQr6QBe44sI/IFchFBvL 2NNIf9glTzbhS/dOWB8ZiBb5mCgVu6Jwyu4cuDmvQEjklaiI3uEGKoPlgZ33Qfjkiv CK+L5STlJFxzg== Received: by paulmck-ThinkPad-P17-Gen-1.home (Postfix, from userid 1000) id 10EC6CE09DB; Thu, 8 Aug 2024 11:02:49 -0700 (PDT) Date: Thu, 8 Aug 2024 11:02:49 -0700 From: "Paul E. McKenney" To: Thorsten Blum Cc: frederic@kernel.org, neeraj.upadhyay@kernel.org, joel@joelfernandes.org, josh@joshtriplett.org, boqun.feng@gmail.com, urezki@gmail.com, rostedt@goodmis.org, mathieu.desnoyers@efficios.com, jiangshanlai@gmail.com, qiang.zhang1211@gmail.com, kees@kernel.org, gustavoars@kernel.org, rcu@vger.kernel.org, linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org Subject: Re: [PATCH] rcu: Annotate struct kvfree_rcu_bulk_data with __counted_by() Message-ID: <2f134298-d41d-4022-a2d5-e89e0c87b00c@paulmck-laptop> Reply-To: paulmck@kernel.org References: <20240807095459.1400-2-thorsten.blum@toblux.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240807095459.1400-2-thorsten.blum@toblux.com> On Wed, Aug 07, 2024 at 11:55:00AM +0200, Thorsten Blum wrote: > Add the __counted_by compiler attribute to the flexible array member > records to improve access bounds-checking via CONFIG_UBSAN_BOUNDS and > CONFIG_FORTIFY_SOURCE. > > Increment nr_records before adding a new pointer to the records array. > > Signed-off-by: Thorsten Blum Reviewed-by: Paul E. McKenney > --- > kernel/rcu/tree.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c > index e641cc681901..76d8d75dd8b3 100644 > --- a/kernel/rcu/tree.c > +++ b/kernel/rcu/tree.c > @@ -3227,7 +3227,7 @@ struct kvfree_rcu_bulk_data { > struct list_head list; > struct rcu_gp_oldstate gp_snap; > unsigned long nr_records; > - void *records[]; > + void *records[] __counted_by(nr_records); > }; > > /* > @@ -3767,7 +3767,8 @@ add_ptr_to_bulk_krc_lock(struct kfree_rcu_cpu **krcp, > } > > // Finally insert and update the GP for this page. > - bnode->records[bnode->nr_records++] = ptr; > + bnode->nr_records++; > + bnode->records[bnode->nr_records - 1] = ptr; > get_state_synchronize_rcu_full(&bnode->gp_snap); > atomic_inc(&(*krcp)->bulk_count[idx]); > > -- > 2.45.2 >