From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BBB8FC33CAF for ; Thu, 16 Jan 2020 18:46:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8C4952064C for ; Thu, 16 Jan 2020 18:46:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579200376; bh=4a7Sk8SWFDzfmkMN30hHFPwBDh9o5W9TF2o7WnL/dco=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=CQaQPLV+FpZTF/4okAj7c7c++zUDDNwQNOAJm6FsPEowjCKdbfsvLndq0e+fblX2a 4eG1EnnjYweTSbTj/Rfkgp0zut5Syq+U4rXnpEj+Sz5PNHULgZSbbfhoqQmWYWXXSW USXzxZJjIhEJvuVr5uLYFnfsuRPmxLyKlSIReuHM= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390859AbgAPSqP (ORCPT ); Thu, 16 Jan 2020 13:46:15 -0500 Received: from mail.kernel.org ([198.145.29.99]:48538 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389931AbgAPRKZ (ORCPT ); Thu, 16 Jan 2020 12:10:25 -0500 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 4A22324684; Thu, 16 Jan 2020 17:10:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579194625; bh=4a7Sk8SWFDzfmkMN30hHFPwBDh9o5W9TF2o7WnL/dco=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=tD22/1xzrGP//aTgHVdcZIihYdesZpZU0JdVUauRDUqGHTnXnukJViigSAy+fF1dk eaE4aMRJBIQ/BlA2Qq1nVGLsKoni8QsB/d4iN1cJ20pFGkH2injtHtqEacKaffxk1Q V5XFuvmr49Hk/Oj6AdkJH2rGh6gsZdgBZsgAMWDQ= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Chuhong Yuan , "David S . Miller" , Sasha Levin , netdev@vger.kernel.org Subject: [PATCH AUTOSEL 4.19 485/671] cxgb4: smt: Add lock for atomic_dec_and_test Date: Thu, 16 Jan 2020 12:02:03 -0500 Message-Id: <20200116170509.12787-222-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200116170509.12787-1-sashal@kernel.org> References: <20200116170509.12787-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Chuhong Yuan [ Upstream commit 4a8937b83892cb69524291cae6cdabad4a8be033 ] The atomic_dec_and_test() is not safe because it is outside of locks. Move the locks of t4_smte_free() to its caller, cxgb4_smt_release() to protect the atomic decrement. Fixes: 3bdb376e6944 ("cxgb4: introduce SMT ops to prepare for SMAC rewrite support") Signed-off-by: Chuhong Yuan Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- drivers/net/ethernet/chelsio/cxgb4/smt.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/chelsio/cxgb4/smt.c b/drivers/net/ethernet/chelsio/cxgb4/smt.c index 7b2207a2a130..9b3f4205cb4d 100644 --- a/drivers/net/ethernet/chelsio/cxgb4/smt.c +++ b/drivers/net/ethernet/chelsio/cxgb4/smt.c @@ -98,11 +98,9 @@ static struct smt_entry *find_or_alloc_smte(struct smt_data *s, u8 *smac) static void t4_smte_free(struct smt_entry *e) { - spin_lock_bh(&e->lock); if (atomic_read(&e->refcnt) == 0) { /* hasn't been recycled */ e->state = SMT_STATE_UNUSED; } - spin_unlock_bh(&e->lock); } /** @@ -112,8 +110,10 @@ static void t4_smte_free(struct smt_entry *e) */ void cxgb4_smt_release(struct smt_entry *e) { + spin_lock_bh(&e->lock); if (atomic_dec_and_test(&e->refcnt)) t4_smte_free(e); + spin_unlock_bh(&e->lock); } EXPORT_SYMBOL(cxgb4_smt_release); -- 2.20.1