From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:41878 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933067AbeBWSmk (ORCPT ); Fri, 23 Feb 2018 13:42:40 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot+76e7efc4748495855a4d@syzkaller.appspotmail.com, syzbot , Laura Abbott Subject: [PATCH 4.9 017/145] staging: android: ion: Add __GFP_NOWARN for system contig heap Date: Fri, 23 Feb 2018 19:25:23 +0100 Message-Id: <20180223170726.880387651@linuxfoundation.org> In-Reply-To: <20180223170724.669759283@linuxfoundation.org> References: <20180223170724.669759283@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Laura Abbott commit 0c75f10312a35b149b2cebb1832316b35c2337ca upstream. syzbot reported a warning from Ion: WARNING: CPU: 1 PID: 3485 at mm/page_alloc.c:3926 ... __alloc_pages_nodemask+0x9fb/0xd80 mm/page_alloc.c:4252 alloc_pages_current+0xb6/0x1e0 mm/mempolicy.c:2036 alloc_pages include/linux/gfp.h:492 [inline] ion_system_contig_heap_allocate+0x40/0x2c0 drivers/staging/android/ion/ion_system_heap.c:374 ion_buffer_create drivers/staging/android/ion/ion.c:93 [inline] ion_alloc+0x2c1/0x9e0 drivers/staging/android/ion/ion.c:420 ion_ioctl+0x26d/0x380 drivers/staging/android/ion/ion-ioctl.c:84 vfs_ioctl fs/ioctl.c:46 [inline] do_vfs_ioctl+0x1b1/0x1520 fs/ioctl.c:686 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692 This is a warning about attempting to allocate order > MAX_ORDER. This is coming from a userspace Ion allocation request. Since userspace is free to request however much memory it wants (and the kernel is free to deny its allocation), silence the allocation attempt with __GFP_NOWARN in case it fails. Reported-by: syzbot+76e7efc4748495855a4d@syzkaller.appspotmail.com Reported-by: syzbot Signed-off-by: Laura Abbott Signed-off-by: Greg Kroah-Hartman --- drivers/staging/android/ion/ion_system_heap.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/staging/android/ion/ion_system_heap.c +++ b/drivers/staging/android/ion/ion_system_heap.c @@ -384,7 +384,7 @@ static int ion_system_contig_heap_alloca if (align > (PAGE_SIZE << order)) return -EINVAL; - page = alloc_pages(low_order_gfp_flags, order); + page = alloc_pages(low_order_gfp_flags | __GFP_NOWARN, order); if (!page) return -ENOMEM;