From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from terminus.zytor.com ([198.137.202.10]:56068 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759038AbcDMLfj (ORCPT ); Wed, 13 Apr 2016 07:35:39 -0400 Date: Wed, 13 Apr 2016 04:35:03 -0700 From: tip-bot for Tony Luck Message-ID: Cc: linux-edac@vger.kernel.org, stable@vger.kernel.org, tony.luck@intel.com, gong.chen@linux.intel.com, tglx@linutronix.de, linux-kernel@vger.kernel.org, mingo@kernel.org, hpa@zytor.com, torvalds@linux-foundation.org, bp@suse.de, peterz@infradead.org Reply-To: torvalds@linux-foundation.org, hpa@zytor.com, mingo@kernel.org, linux-kernel@vger.kernel.org, bp@suse.de, peterz@infradead.org, stable@vger.kernel.org, linux-edac@vger.kernel.org, tglx@linutronix.de, gong.chen@linux.intel.com, tony.luck@intel.com In-Reply-To: <1459929916-12852-4-git-send-email-bp@alien8.de> References: <0205920@agluck-desk.sc.intel.com> <1459929916-12852-4-git-send-email-bp@alien8.de> To: linux-tip-commits@vger.kernel.org Subject: [tip:ras/core] x86/mce: Avoid using object after free in genpool MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: stable-owner@vger.kernel.org List-ID: Commit-ID: a3125494cff084b098c80bb36fbe2061ffed9d52 Gitweb: http://git.kernel.org/tip/a3125494cff084b098c80bb36fbe2061ffed9d52 Author: Tony Luck AuthorDate: Wed, 6 Apr 2016 10:05:16 +0200 Committer: Ingo Molnar CommitDate: Wed, 13 Apr 2016 10:54:00 +0200 x86/mce: Avoid using object after free in genpool When we loop over all queued machine check error records to pass them to the registered notifiers we use llist_for_each_entry(). But the loop calls gen_pool_free() for the entry in the body of the loop - and then the iterator looks at node->next after the free. Use llist_for_each_entry_safe() instead. Signed-off-by: Tony Luck Signed-off-by: Borislav Petkov Cc: Cc: Gong Chen Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-edac Link: http://lkml.kernel.org/r/0205920@agluck-desk.sc.intel.com Link: http://lkml.kernel.org/r/1459929916-12852-4-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar --- arch/x86/kernel/cpu/mcheck/mce-genpool.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/x86/kernel/cpu/mcheck/mce-genpool.c b/arch/x86/kernel/cpu/mcheck/mce-genpool.c index 0a85010..2658e2a 100644 --- a/arch/x86/kernel/cpu/mcheck/mce-genpool.c +++ b/arch/x86/kernel/cpu/mcheck/mce-genpool.c @@ -29,7 +29,7 @@ static char gen_pool_buf[MCE_POOLSZ]; void mce_gen_pool_process(void) { struct llist_node *head; - struct mce_evt_llist *node; + struct mce_evt_llist *node, *tmp; struct mce *mce; head = llist_del_all(&mce_event_llist); @@ -37,7 +37,7 @@ void mce_gen_pool_process(void) return; head = llist_reverse_order(head); - llist_for_each_entry(node, head, llnode) { + llist_for_each_entry_safe(node, tmp, head, llnode) { mce = &node->mce; atomic_notifier_call_chain(&x86_mce_decoder_chain, 0, mce); gen_pool_free(mce_evt_pool, (unsigned long)node, sizeof(*node));