From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793213541; b=3CWTMwVKPsIQCl51DjVVE0y34AW6noja3qtb9zLZDdKp6FwgkmYDC8ByWZ6GAkKz0xGm khjxBybJE1M2bwRroMwqt+ysx9vxmmXEKI9tpVqanhvdrIfGi2xwn853uegrslCfFhwjQ 0dJMwp5r+E0vSRQmnp+sZDS4J5Y4EC0hgjLoKi52RZXNrYc7bI4N+LPXgnQPGztxFjyZz ubln6AchX1QYZ/4Xf5HnWWnB/b5euce5VR7GT1i7+KqizddeoxSyOlvwNfqRUcq8cDN1Z nGY9d2ReIZZAQGEParHEfCWBLYBDEWq7qMibwi67nacq0nj9jKMcqMQBHyF5WPxL/vA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793213541; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Transfer-Encoding; bh=1n4/yyqUVSR+RLPrMtSrtYYveCXVjSo2NhF+W+v7g7E=; b=FpKeFfdYs4shDQ6mXR96iwrrMjt8nXovdhzpDzoRp3BkcVkiAR1u8vY6uh37v0YreuTZ K4mFnXDBQLEiR73LtHqxesDeuqXBMuHgPmzBk2PT4NiRHsOsQXW75ki5eyQXW3WLTq0Sf +1GNql796gftkc5KtUp90QK3m9e22fHYO1fr0qkBefLT+KUf4urA9isl72xmk63Rs/xgv Jle9kZ9cYxQhuvtgHjFAjx6TmajDmULqOb29CRoT77ZbTFs3ZgWMwjFXomJEx/C9RvUoT M4IV6ysgAImTCS4sKboPOmvyc/MisaOd3eCAKWsN7vJ3mODuhCPsjzijG70HtsUbM2A== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=ZM3W8Coy; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 14AD3606A31D; Wed, 28 Oct 2026 18:52:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=ZM3W8Coy Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2E87F1F031E1; Wed, 28 Oct 2026 18:52:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1793213540; bh=1n4/yyqUVSR+RLPrMtSrtYYveCXVjSo2NhF+W+v7g7E=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=ZM3W8Coy9XzZun3Dp/SbOrpe2PRJQQIw7mOjm5qdEiKwJI/i84vMpG3GO3muA7VvY a9n9p88twGDb8Eeou7Apq52xnNiu4dWgoIGmUBBwfEvFJ6bjumQtEzLMzDpySR9H8/ e11D20s4igcYwTWgk9cRLtFk49697HCj3AayCdHs= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, "Christian Brauner (Amutable)" , Sasha Levin Subject: [PATCH 6.1 0543/1887] fcntl: refuse F_SET_RW_HINT on an immutable inode Date: Wed, 28 Oct 2026 17:43:59 +0100 Message-ID: <20261028170511.714402122@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261028170459.200466217@linuxfoundation.org> References: <20261028170459.200466217@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: patches@lists.linux.dev List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Christian Brauner [ Upstream commit b0d1022b9bdb1e98aa7fb3244fdd50a58c61766c ] An immutable inode is never written to so write hints are pointless. Refuse the hint on an immutable inode the way setattr(), fallocate() and etxattr() refuse their changes. Fixes: c75b1d9421f8 ("fs: add fcntl() interface for setting/getting write life time hints") Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20261002-work-mount-fixes-4-v1-3-dd44b89d44ce@kernel.org Signed-off-by: Christian Brauner (Amutable) [ sashal: Moved the check from fcntl_set_rw_hint() to the F_SET_RW_HINT case in the combined fcntl_rw_hint() helper. ] Signed-off-by: Sasha Levin --- fs/fcntl.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/fs/fcntl.c b/fs/fcntl.c index 1bde178e4aa2e..13ba6b47877b8 100644 --- a/fs/fcntl.c +++ b/fs/fcntl.c @@ -290,6 +290,9 @@ static long fcntl_rw_hint(struct file *file, unsigned int cmd, return -EFAULT; return 0; case F_SET_RW_HINT: + /* nothing is ever written to it */ + if (IS_IMMUTABLE(inode)) + return -EPERM; if (copy_from_user(&hint, argp, sizeof(hint))) return -EFAULT; if (!rw_hint_valid(hint)) -- 2.53.0