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 64CE2C4167B for ; Mon, 6 Nov 2023 23:27:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233911AbjKFX1G (ORCPT ); Mon, 6 Nov 2023 18:27:06 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54902 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233981AbjKFX0w (ORCPT ); Mon, 6 Nov 2023 18:26:52 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 77797384F; Mon, 6 Nov 2023 15:22:23 -0800 (PST) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9B0C2C116AF; Mon, 6 Nov 2023 23:17:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1699312635; bh=syqVOaVrco9HeHy4U5pQqP2otlgkEbvxhduOTsJjKzg=; h=From:To:Cc:Subject:Date:From; b=LAQJkY+Iub58uJyQG05oEneJhRjDu+tTwmwnDNQ4jgFTudrbrh9aOoCkGfoC1gw4o FcGucyTuKEDzzH0kdBFKgVdN7Oe8o2tmnCVONURkmrgBkFlKdKvR8TWkPlQU19Jy4g Lm5MxK/O2mEW/O/5EFJWACcuHScJ69TuR+hOHBP3Ur14Tlm5nRdDRg0R8U2ASD20zY 56r+hSqz4G5UPp2zMWyB12xzcHuU2KDlbMPBSW19A9/NooXsnOGx4O3mEpTFEP8KTj OSqU1j+FwVFEtFL5bTh0ZJkRjZS//orgIPhMe+bsTumHwHCzyqJjAloH2/AZEe6EsY ALMsskwfAJbBQ== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Shuai Xue , Peter Zijlstra , Ingo Molnar , Sasha Levin , mingo@redhat.com, acme@kernel.org, linux-perf-users@vger.kernel.org Subject: [PATCH AUTOSEL 4.19 1/5] perf/core: Bail out early if the request AUX area is out of bound Date: Mon, 6 Nov 2023 18:17:04 -0500 Message-ID: <20231106231711.3735997-1-sashal@kernel.org> X-Mailer: git-send-email 2.42.0 MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 4.19.297 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Shuai Xue [ Upstream commit 54aee5f15b83437f23b2b2469bcf21bdd9823916 ] When perf-record with a large AUX area, e.g 4GB, it fails with: #perf record -C 0 -m ,4G -e arm_spe_0// -- sleep 1 failed to mmap with 12 (Cannot allocate memory) and it reveals a WARNING with __alloc_pages(): ------------[ cut here ]------------ WARNING: CPU: 44 PID: 17573 at mm/page_alloc.c:5568 __alloc_pages+0x1ec/0x248 Call trace: __alloc_pages+0x1ec/0x248 __kmalloc_large_node+0xc0/0x1f8 __kmalloc_node+0x134/0x1e8 rb_alloc_aux+0xe0/0x298 perf_mmap+0x440/0x660 mmap_region+0x308/0x8a8 do_mmap+0x3c0/0x528 vm_mmap_pgoff+0xf4/0x1b8 ksys_mmap_pgoff+0x18c/0x218 __arm64_sys_mmap+0x38/0x58 invoke_syscall+0x50/0x128 el0_svc_common.constprop.0+0x58/0x188 do_el0_svc+0x34/0x50 el0_svc+0x34/0x108 el0t_64_sync_handler+0xb8/0xc0 el0t_64_sync+0x1a4/0x1a8 'rb->aux_pages' allocated by kcalloc() is a pointer array which is used to maintains AUX trace pages. The allocated page for this array is physically contiguous (and virtually contiguous) with an order of 0..MAX_ORDER. If the size of pointer array crosses the limitation set by MAX_ORDER, it reveals a WARNING. So bail out early with -ENOMEM if the request AUX area is out of bound, e.g.: #perf record -C 0 -m ,4G -e arm_spe_0// -- sleep 1 failed to mmap with 12 (Cannot allocate memory) Signed-off-by: Shuai Xue Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Ingo Molnar Signed-off-by: Sasha Levin --- kernel/events/ring_buffer.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/kernel/events/ring_buffer.c b/kernel/events/ring_buffer.c index 12f351b253bbb..2f6f77658eba2 100644 --- a/kernel/events/ring_buffer.c +++ b/kernel/events/ring_buffer.c @@ -639,6 +639,12 @@ int rb_alloc_aux(struct ring_buffer *rb, struct perf_event *event, } } + /* + * kcalloc_node() is unable to allocate buffer if the size is larger + * than: PAGE_SIZE << MAX_ORDER; directly bail out in this case. + */ + if (get_order((unsigned long)nr_pages * sizeof(void *)) > MAX_ORDER) + return -ENOMEM; rb->aux_pages = kcalloc_node(nr_pages, sizeof(void *), GFP_KERNEL, node); if (!rb->aux_pages) -- 2.42.0