Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S967658AbXEHDDP (ORCPT ); Mon, 7 May 2007 23:03:15 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S967643AbXEHDDL (ORCPT ); Mon, 7 May 2007 23:03:11 -0400 Received: from wr-out-0506.google.com ([64.233.184.231]:11978 "EHLO wr-out-0506.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S967630AbXEHDDJ (ORCPT ); Mon, 7 May 2007 23:03:09 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:message-id:date:from:to:subject:mime-version:content-type:content-transfer-encoding:content-disposition; b=pBi8L1VCV1OkyaE71gzQmglubZIxH/JydIseyO/RddVTdYqNpm8rM/E8KxdqsAxmMahBY6qXuwUC0rEMM55gmMtfdCQZxpjSwXSWALBMjwOpf5Bu5lrim86OJEFZziZS1hJi0pp+eXVpXQBX6lT29lvH7OdML4STlfNb94uKk+Y= Message-ID: Date: Tue, 8 May 2007 07:03:08 +0400 From: "Dan Kruchinin" To: linux-kernel@vger.kernel.org, "Andrew Morton" Subject: [PATCH -mm] drivers/usb/core/config.c: kzalloc(0,..) MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2553 Lines: 70 The following patch fixes such SLUB report(when someone tries to allocate 0 bytes): -- May 8 00:19:15 midgard kernel: [ 21.933467] BUG: at include/linux/slub_def.h:88 kmalloc_index() May 8 00:19:15 midgard kernel: [ 21.933470] [show_registers+410/736] show_trace_log_lvl+0x1a/0x30 May 8 00:19:15 midgard kernel: [ 21.933478] [print_trace_warning_symbol+50/64] show_trace+0x12/0x20 May 8 00:19:15 midgard kernel: [ 21.933482] [fixup_irqs+38/192] dump_stack+0x16/0x20 May 8 00:19:15 midgard kernel: [ 21.933485] [do_lookup+195/400] get_slab+0x213/0x230 May 8 00:19:15 midgard kernel: [ 21.933489] [do_lookup+309/400] __kmalloc_track_caller+0x15/0x40 May 8 00:19:15 midgard kernel: [ 21.933493] [__vunmap+25/240] __kzalloc+0x19/0x50 May 8 00:19:15 midgard kernel: [ 21.933498] [] usb_parse_configuration+0x85e/0xe70 [usbcore] May 8 00:19:15 midgard kernel: [ 21.933520] [] usb_get_configuration+0x12b/0x450 [usbcore] May 8 00:19:15 midgard kernel: [ 21.933535] [] usb_new_device+0x17/0x1c0 [usbcore] May 8 00:19:15 midgard kernel: [ 21.933550] [] hub_thread+0x79a/0xfd0 [usbcore] May 8 00:19:15 midgard kernel: [ 21.933564] [run_posix_cpu_timers+1218/2064] kthread+0x42/0x70 May 8 00:19:15 midgard kernel: [ 21.933569] [math_error+87/240] kernel_thread_helper+0x7/0x10 May 8 00:19:15 midgard kernel: [ 21.933572] ======================= -- The problem was in drivers/usb/core/config.c in function usb_parse_interface: --- num_ep = num_ep_orig = alt->desc.bNumEndpoints; ... len = sizeof(struct usb_host_endpoint) * num_ep; alt->endpoint = kzalloc(len, GFP_KERNEL); --- num_ep can be 0, as it was in my case, so following patch makes this situation more obvious and clear. -------------- diff --git a/drivers/usb/core/config.c b/drivers/usb/core/config.c index bfb3731..4db6b21 100644 --- a/drivers/usb/core/config.c +++ b/drivers/usb/core/config.c @@ -185,7 +185,10 @@ static int usb_parse_interface(struct device *ddev, int cfgno, num_ep = USB_MAXENDPOINTS; } - len = sizeof(struct usb_host_endpoint) * num_ep; + len = sizeof(struct usb_host_endpoint); + if (num_ep > 0) + len *= num_ep; + alt->endpoint = kzalloc(len, GFP_KERNEL); if (!alt->endpoint) return -ENOMEM; --------------- Dan Kruchinin. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/