Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757079Ab2EUQuD (ORCPT ); Mon, 21 May 2012 12:50:03 -0400 Received: from relay1.sgi.com ([192.48.179.29]:54435 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756912Ab2EUQuB (ORCPT ); Mon, 21 May 2012 12:50:01 -0400 Date: Mon, 21 May 2012 11:49:59 -0500 From: Dimitri Sivanich To: Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , x86@kernel.org, Suresh Siddha , Yinghai Lu , Naga Chumbalkar , Jacob Pan , linux-kernel@vger.kernel.org Subject: [PATCH] x86: check for valid irq_cfg pointer in smp_irq_move_cleanup_interrupt Message-ID: <20120521164959.GE16454@sgi.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1106 Lines: 32 The smp_irq_move_cleanup_interrupt routine should be checking for a valid irq_cfg pointer prior to accessing it. It also seems that this should be done after taking the desc lock. Signed-off-by: Dimitri Sivanich --- arch/x86/kernel/apic/io_apic.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) Index: linux/arch/x86/kernel/apic/io_apic.c =================================================================== --- linux.orig/arch/x86/kernel/apic/io_apic.c +++ linux/arch/x86/kernel/apic/io_apic.c @@ -2478,9 +2478,12 @@ asmlinkage void smp_irq_move_cleanup_int if (!desc) continue; - cfg = irq_cfg(irq); raw_spin_lock(&desc->lock); + cfg = irq_cfg(irq); + if (!cfg) + goto unlock; + /* * Check if the irq migration is in progress. If so, we * haven't received the cleanup request yet for this irq. -- 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/