From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CC990339BE; Fri, 24 Nov 2023 19:01:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="GAisfift" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 57A49C433C8; Fri, 24 Nov 2023 19:01:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1700852503; bh=5CBIdEdPZmODBF2WZzX8AH1b1MDY3I590m2rRWjSWkk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=GAisfift0WX8y6YUA2VgRPeRnEhgOmdOQdWYEfaJMCNnAaQJZ0s4SoSUkmzWAGoq9 Ak9BLYhUacacjz/carGHZQCFo1Tv3iIpl7pFyQCQJLWi5rOTM76PFaD7E0r7WCAsRy MEKZVWF4vv2DNPHgwYpTeG+Y65zWeLkyU0QV4y/E= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Shuai Xue , "Peter Zijlstra (Intel)" , Ingo Molnar , Sasha Levin Subject: [PATCH 5.10 002/193] perf/core: Bail out early if the request AUX area is out of bound Date: Fri, 24 Nov 2023 17:52:09 +0000 Message-ID: <20231124171947.225398449@linuxfoundation.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20231124171947.127438872@linuxfoundation.org> References: <20231124171947.127438872@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.10-stable review patch. If anyone has any objections, please let me know. ------------------ 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 4032cd4750001..01351e7e25435 100644 --- a/kernel/events/ring_buffer.c +++ b/kernel/events/ring_buffer.c @@ -691,6 +691,12 @@ int rb_alloc_aux(struct perf_buffer *rb, struct perf_event *event, max_order--; } + /* + * 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