From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CB0E4C433EF for ; Tue, 28 Dec 2021 13:51:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232889AbhL1Nvu (ORCPT ); Tue, 28 Dec 2021 08:51:50 -0500 Received: from dfw.source.kernel.org ([139.178.84.217]:39754 "EHLO dfw.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231989AbhL1Nvu (ORCPT ); Tue, 28 Dec 2021 08:51:50 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 4049E611B8 for ; Tue, 28 Dec 2021 13:51:50 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 036D9C36AE7; Tue, 28 Dec 2021 13:51:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1640699509; bh=7L6sBeGTeAI0nwLgE9k2BvtSgHm1w5CZeGELqMaiYKU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=C/SPq1TNEXpZO4JqwythO25vzq23jSWKqeZZ08ZDbe3k1ZBKvmhVax16eSRwO21uL BalpfLnIZGlnVFTVI+Vj18YJi0ZR/cqDxUWh0aPz4v4D2Jb5/kbfA4nl8ks8LCUK5o Tn8VWBmJBqEqwBh5sMOHCMWWHLXFSh/gZuoovopY= Date: Tue, 28 Dec 2021 14:51:46 +0100 From: Greg Kroah-Hartman To: Shile Zhang Cc: David Airlie , Daniel Vetter , Wen Kang , stable@vger.kernel.org Subject: Re: [PATCH 5.10.y] drm/cirrus: fix a NULL vs IS_ERR() checks Message-ID: References: <20211228132556.108711-1-shile.zhang@linux.alibaba.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20211228132556.108711-1-shile.zhang@linux.alibaba.com> Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On Tue, Dec 28, 2021 at 09:25:56PM +0800, Shile Zhang wrote: > The function drm_gem_shmem_vmap can returns error pointers as well, > which could cause following kernel crash: > > BUG: unable to handle page fault for address: fffffffffffffffc > PGD 1426a12067 P4D 1426a12067 PUD 1426a14067 PMD 0 > Oops: 0000 [#1] SMP NOPTI > CPU: 12 PID: 3598532 Comm: stress-ng Kdump: loaded Not tainted 5.10.50.x86_64 #1 > ... > RIP: 0010:memcpy_toio+0x23/0x50 > Code: 00 00 00 00 0f 1f 00 0f 1f 44 00 00 48 85 d2 74 28 40 f6 c7 01 75 2b 48 83 fa 01 76 06 40 f6 c7 02 75 17 48 89 d1 48 c1 e9 02 a5 f6 c2 02 74 02 66 a5 f6 c2 01 74 01 a4 c3 66 a5 48 83 ea 02 > RSP: 0018:ffffafbf8a203c68 EFLAGS: 00010216 > RAX: 0000000000000000 RBX: fffffffffffffffc RCX: 0000000000000200 > RDX: 0000000000000800 RSI: fffffffffffffffc RDI: ffffafbf82000000 > RBP: ffffafbf82000000 R08: 0000000000000002 R09: 0000000000000000 > R10: 00000000000002b5 R11: 0000000000000000 R12: 0000000000000800 > R13: ffff8a6801099300 R14: 0000000000000001 R15: 0000000000000300 > FS: 00007f4a6bc5f740(0000) GS:ffff8a8641900000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: fffffffffffffffc CR3: 00000016d3874001 CR4: 00000000003606e0 > Call Trace: > drm_fb_memcpy_dstclip+0x5e/0x80 [drm_kms_helper] > cirrus_fb_blit_rect.isra.0+0xb7/0xe0 [cirrus] > cirrus_pipe_update+0x9f/0xa8 [cirrus] > drm_atomic_helper_commit_planes+0xb8/0x220 [drm_kms_helper] > drm_atomic_helper_commit_tail+0x42/0x80 [drm_kms_helper] > commit_tail+0xce/0x130 [drm_kms_helper] > drm_atomic_helper_commit+0x113/0x140 [drm_kms_helper] > drm_client_modeset_commit_atomic+0x1c4/0x200 [drm] > drm_client_modeset_commit_locked+0x53/0x80 [drm] > drm_client_modeset_commit+0x24/0x40 [drm] > drm_fbdev_client_restore+0x48/0x85 [drm_kms_helper] > drm_client_dev_restore+0x64/0xb0 [drm] > drm_release+0xf2/0x110 [drm] > __fput+0x96/0x240 > task_work_run+0x5c/0x90 > exit_to_user_mode_loop+0xce/0xd0 > exit_to_user_mode_prepare+0x6a/0x70 > syscall_exit_to_user_mode+0x12/0x40 > entry_SYSCALL_64_after_hwframe+0x44/0xa9 > RIP: 0033:0x7f4a6bd82c2b > > Fixes: ab3e023b1b4c9 ("drm/cirrus: rewrite and modernize driver.") > > CC: stable@vger.kernel.org > Reported-by: Wen Kang > Signed-off-by: Shile Zhang > --- > drivers/gpu/drm/tiny/cirrus.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) What is the git commit id of this patch in Linus's tree? thanks, greg k-h