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=1794063314; b=S/UnVPIz8IdQ+n6Zj7mJpluvFuaiDbmtldp1NoMDVnuhbk9Gwi/fiA4TbOS3Oggt7OYA l+03ufe7MRmcOJ5yACyGFQpvnqM8te3f2FN2SERCb60HX/YDYzLgX/TPL9wpg7+/jk+5N 8/wTbt4tLeBE+xFN09cp8mOpI7G3dxuJkcKyYpP9qX6qdIBtmDZjePXbAgochzFRRWe2r 97XZbDDXC1wBH7CdBJQNPRSkoeVSwpwjt9NrzBm90N5GDF32mQsqeJFEqR7jbrgH3D70A n64S6gA1CGSyrzZLEiEJfoMjOIiic1pobPiZslhrndk/REp5wgLZHQNHNhLwa5gUFcw== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794063314; 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=whd81ZCz5u2bpeeUifRXgcdPI7z679dvmF09JSNZa8U=; b=XOJdxuLzgxhinxhkgMpBwfOWVpjJvFfjq12Cza9km17PY2Im/IwmdnCaCvy7PYGm0Tr1 690VdJl6ZCkl1E6Y3dHMvgHyFQK3DoVOpNyX5+DNSvTJo02wPqtbH0MIHODMnB4qNk0dB WUX20g/yA55+n7+f89Zs/GEQ9mApcYHEXZVWRt/zaMlcDBDFchxPWNuBK0g6AjZbJbFn6 i1qOjbZr2a34p35REEJg+hP2HkiOqxZzOpG2DGq/mbJeqIkKVKVku9q1YLn7mwpne1W43 VhC5BIgnKF4/fd/jTFGLJYwqVffSZrlj8hG8Y4ZehyRPe483qFXK3HNL4thiE5k5jpQ== 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=ro6JpRfs; 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 C5B27606A32C; Sat, 7 Nov 2026 14:55:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=ro6JpRfs Received: by smtp.kernel.org (Postfix) with ESMTPSA id 659D81F008A2; Sat, 7 Nov 2026 14:55:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1794063313; bh=whd81ZCz5u2bpeeUifRXgcdPI7z679dvmF09JSNZa8U=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=ro6JpRfsQ10lFJgXbk/EsTiMZEcADAobdNZWI6sOZxHyWQBE3QgKfWFIei8itMnso SNmDjIx3f0CPzQh9pJEKK4dEf9JVlla550EPUxImhPZ0uvmqo9aZC/Qb1ul9nUHh56 3k0bqgroWvj7fS0JbQWVOZeaoAFZK2ru0SHfvdKQ= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, "Lorenzo Stoakes (ARM)" , Helge Deller , Sasha Levin Subject: [PATCH 6.18 501/869] fbdev: xen-fbfront: check for fb_deferred_io_init() error Date: Sat, 7 Nov 2026 08:53:03 -0500 Message-ID: <20261107134910.613388046@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261107134852.069646174@linuxfoundation.org> References: <20261107134852.069646174@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: stable@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Lorenzo Stoakes (ARM) [ Upstream commit 5b234b0dd29d79207c059c7b40851dd1e934fa3a ] fb_deferred_io_init() allocates deferred I/O state, populating info->fbdefio_state, or leaving it NULL if an error occurs. Currently xenfb_probe() ignores its return value. Therefore if an error arises in fb_deferred_io_init() (for instance, due to an allocation failure) info->fbdefio_state is left NULL. When the file is subsequently opened, fb_open() will dereference a NULL pointer (calling fb_deferred_io_open()). Fix this by checking for the error. Fixes: 56c134f7f1b5 ("fbdev: Track deferred-I/O pages in pageref struct") Cc: stable@vger.kernel.org Signed-off-by: Lorenzo Stoakes (ARM) Signed-off-by: Helge Deller Signed-off-by: Sasha Levin --- drivers/video/fbdev/xen-fbfront.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/video/fbdev/xen-fbfront.c b/drivers/video/fbdev/xen-fbfront.c index d8f3bfb2dd6c9..22aaafd2c11f5 100644 --- a/drivers/video/fbdev/xen-fbfront.c +++ b/drivers/video/fbdev/xen-fbfront.c @@ -443,7 +443,11 @@ static int xenfb_probe(struct xenbus_device *dev, } fb_info->fbdefio = &xenfb_defio; - fb_deferred_io_init(fb_info); + ret = fb_deferred_io_init(fb_info); + if (ret < 0) { + xenbus_dev_fatal(dev, ret, "fb_deferred_io_init"); + goto error_cmap; + } xenfb_init_shared_page(info, fb_info); @@ -465,6 +469,7 @@ static int xenfb_probe(struct xenbus_device *dev, error_fb: fb_deferred_io_cleanup(fb_info); +error_cmap: fb_dealloc_cmap(&fb_info->cmap); framebuffer_release(fb_info); error_nomem: -- 2.53.0