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 413EC3184DA; Mon, 5 May 2025 22:31:10 +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=1746484270; cv=none; b=WCVY9B52ns+/2bDLjN3k3PkXzKvhUHwDRh8mmnRIOO7d/QJm1reC/y++txl4awO938HK/QEIlLvr3qub/W4KvQvhi3bRbSauUybOtfr6mMK1zJCzbzQN6n8u7VZhg9JYdH8Waina1ZW9iQ906JLN5DpNfUcXpQUjwPOiV5b8370= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746484270; c=relaxed/simple; bh=pwIrPYe2moK7L7uJ3vTZLVwNuFiG5U0eZA331dBMFMM=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=NTI6UfRUhmk4k+jG1IymF7ZcjHJ6QotSSj6d6h5UryjazI+OI/EpKfbOGaKKQ6j/LtQuoXdub7H5JUfbRI2W7GsolqLk5hoTvOl+aZJrVRr9s7AhcquERAb/j8R3g2rLRRhVTUL5jxfhI2qjel1zcKkUljjuR4qjN6ub9700J+U= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=bBgE6vRu; 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="bBgE6vRu" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 70D4BC4CEE4; Mon, 5 May 2025 22:31:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1746484270; bh=pwIrPYe2moK7L7uJ3vTZLVwNuFiG5U0eZA331dBMFMM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=bBgE6vRu4q6szLzYtbwQ5Qj8oFa5q9mxZOo0RhPhk2/rK8PfJNq+hMUcRUuwP9R1A vAoLylUjAMJ0OkEQ8LGP2zzEzGC9uk/cg4WVCr9oJRDcjNILBQtPH+SImA732CwhL9 P5sl1XX3MdshbQR8fhDsnbWO5dJySx5M/ktojnoHJeIem5mHF/Y84q7KjN0kkOztNg frHMwqyAMPlBF3V7okNJSQN5OQaIyaJMe+BXJMT71xIsRYkbOc705uEdD1r3H34Cro ZE4jDxc2SVX1RLxY3nLYEbUM+Bh3GCR86GIbFBFKUaTLqUpjpUhHj49j1eAoAtO2VJ DriSD7lmzUtqA== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Sebastian Andrzej Siewior , Tejun Heo , Greg Kroah-Hartman , Sasha Levin Subject: [PATCH AUTOSEL 6.14 425/642] kernfs: Acquire kernfs_rwsem in kernfs_node_dentry(). Date: Mon, 5 May 2025 18:10:41 -0400 Message-Id: <20250505221419.2672473-425-sashal@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250505221419.2672473-1-sashal@kernel.org> References: <20250505221419.2672473-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.14.5 Content-Transfer-Encoding: 8bit From: Sebastian Andrzej Siewior [ Upstream commit 5b2fabf7fe8f745ff214ff003e6067b64f172271 ] kernfs_node_dentry() passes kernfs_node::name to lookup_positive_unlocked(). Acquire kernfs_root::kernfs_rwsem to ensure the node is not renamed during the operation. Acked-by: Tejun Heo Signed-off-by: Sebastian Andrzej Siewior Link: https://lore.kernel.org/r/20250213145023.2820193-4-bigeasy@linutronix.de Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- fs/kernfs/mount.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/fs/kernfs/mount.c b/fs/kernfs/mount.c index 1358c21837f1a..0f6379ae258d1 100644 --- a/fs/kernfs/mount.c +++ b/fs/kernfs/mount.c @@ -207,6 +207,7 @@ struct dentry *kernfs_node_dentry(struct kernfs_node *kn, { struct dentry *dentry; struct kernfs_node *knparent; + struct kernfs_root *root; BUG_ON(sb->s_op != &kernfs_sops); @@ -216,6 +217,9 @@ struct dentry *kernfs_node_dentry(struct kernfs_node *kn, if (!kn->parent) return dentry; + root = kernfs_root(kn); + guard(rwsem_read)(&root->kernfs_rwsem); + knparent = find_next_ancestor(kn, NULL); if (WARN_ON(!knparent)) { dput(dentry); -- 2.39.5