Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756523Ab2KNFvc (ORCPT ); Wed, 14 Nov 2012 00:51:32 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:55342 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932450Ab2KNFvT (ORCPT ); Wed, 14 Nov 2012 00:51:19 -0500 Message-Id: <20121114053936.947604243@decadent.org.uk> User-Agent: quilt/0.60-1 Date: Wed, 14 Nov 2012 05:39:55 +0000 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Jussi Kivilinna , Gurucharan Shetty , Herbert Xu Subject: [ 22/82] crypto: cryptd - disable softirqs in cryptd_queue_worker to prevent data corruption In-Reply-To: <20121114053933.726869752@decadent.org.uk> X-SA-Exim-Connect-IP: 2001:470:1f08:1539:21c:bfff:fe03:f805 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2200 Lines: 60 3.2-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jussi Kivilinna commit 9efade1b3e981f5064f9db9ca971b4dc7557ae42 upstream. cryptd_queue_worker attempts to prevent simultaneous accesses to crypto workqueue by cryptd_enqueue_request using preempt_disable/preempt_enable. However cryptd_enqueue_request might be called from softirq context, so add local_bh_disable/local_bh_enable to prevent data corruption and panics. Bug report at http://marc.info/?l=linux-crypto-vger&m=134858649616319&w=2 v2: - Disable software interrupts instead of hardware interrupts Reported-by: Gurucharan Shetty Signed-off-by: Jussi Kivilinna Signed-off-by: Herbert Xu Signed-off-by: Ben Hutchings --- crypto/cryptd.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/crypto/cryptd.c b/crypto/cryptd.c index 671d4d6..7bdd61b 100644 --- a/crypto/cryptd.c +++ b/crypto/cryptd.c @@ -137,13 +137,18 @@ static void cryptd_queue_worker(struct work_struct *work) struct crypto_async_request *req, *backlog; cpu_queue = container_of(work, struct cryptd_cpu_queue, work); - /* Only handle one request at a time to avoid hogging crypto - * workqueue. preempt_disable/enable is used to prevent - * being preempted by cryptd_enqueue_request() */ + /* + * Only handle one request at a time to avoid hogging crypto workqueue. + * preempt_disable/enable is used to prevent being preempted by + * cryptd_enqueue_request(). local_bh_disable/enable is used to prevent + * cryptd_enqueue_request() being accessed from software interrupts. + */ + local_bh_disable(); preempt_disable(); backlog = crypto_get_backlog(&cpu_queue->queue); req = crypto_dequeue_request(&cpu_queue->queue); preempt_enable(); + local_bh_enable(); if (!req) return; -- 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/