From nobody Tue Oct 7 05:45:22 2025 Received: from szxga06-in.huawei.com (szxga06-in.huawei.com [45.249.212.32]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4D0991E5018; Mon, 14 Jul 2025 08:00:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.32 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752480046; cv=none; b=STNlCWIFnxTRcU3VoAIxCJDNDal/tGF6fJiP0lN/mg1JlsbjnmQqt7Ib65c4RoGbmSY5ONZMw5M+S1ERpr3wm5C5JcRjgDCv8vDXOzF2lC09g3aQo12AqAELUDtjdoN2gpvf3BjyePcs6Yr8pYPetmwYWCiT7j9UWgJJLyIfteE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752480046; c=relaxed/simple; bh=ovdHmcxQBDLvdoPNAvCtEcdM4Jq392cLtSD1+SWOnXI=; h=From:To:CC:Subject:Date:Message-ID:MIME-Version:Content-Type; b=lA7MvyqQO7hyhjPrmjSXdnMsIKksJMghNsZXJWYh2B1wErpas3Eh1y0semYU2X7LywIyr/cU39rhr0O0DXsrVQGXwakonVvDwoFfO26WMgOHrJadNCSjYMXuHL/ctVNFGJWX1qvQ1sVaP1vzpZ/eTtWSqpPYjHsUWQHPXmYcgLA= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com; spf=pass smtp.mailfrom=huawei.com; arc=none smtp.client-ip=45.249.212.32 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huawei.com Received: from mail.maildlp.com (unknown [172.19.88.214]) by szxga06-in.huawei.com (SkyGuard) with ESMTP id 4bgZXL6xm8z2YPsC; Mon, 14 Jul 2025 16:01:38 +0800 (CST) Received: from dggpemf500002.china.huawei.com (unknown [7.185.36.57]) by mail.maildlp.com (Postfix) with ESMTPS id 5D7071A016C; Mon, 14 Jul 2025 16:00:40 +0800 (CST) Received: from huawei.com (10.175.124.27) by dggpemf500002.china.huawei.com (7.185.36.57) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.11; Mon, 14 Jul 2025 16:00:39 +0800 From: Yue Haibing To: , , , , , CC: , , , , Subject: [PATCH v2 net-next] ipv6: mcast: Avoid a duplicate pointer check in mld_del_delrec() Date: Mon, 14 Jul 2025 16:19:49 +0800 Message-ID: <20250714081949.3109947-1-yuehaibing@huawei.com> X-Mailer: git-send-email 2.34.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-ClientProxiedBy: kwepems500001.china.huawei.com (7.221.188.70) To dggpemf500002.china.huawei.com (7.185.36.57) Content-Type: text/plain; charset="utf-8" Avoid duplicate non-null pointer check for pmc in mld_del_delrec(). No functional changes. Signed-off-by: Yue Haibing Reviewed-by: Kuniyuki Iwashima --- v2: early return if (!pcm) true as Kuniyuki Iwashima suggested, also revise= title --- net/ipv6/mcast.c | 52 +++++++++++++++++++++++------------------------- 1 file changed, 25 insertions(+), 27 deletions(-) diff --git a/net/ipv6/mcast.c b/net/ipv6/mcast.c index 6c875721d423..6d737815d0ab 100644 --- a/net/ipv6/mcast.c +++ b/net/ipv6/mcast.c @@ -789,34 +789,32 @@ static void mld_del_delrec(struct inet6_dev *idev, st= ruct ifmcaddr6 *im) break; pmc_prev =3D pmc; } - if (pmc) { - if (pmc_prev) - rcu_assign_pointer(pmc_prev->next, pmc->next); - else - rcu_assign_pointer(idev->mc_tomb, pmc->next); - } - - if (pmc) { - im->idev =3D pmc->idev; - if (im->mca_sfmode =3D=3D MCAST_INCLUDE) { - tomb =3D rcu_replace_pointer(im->mca_tomb, - mc_dereference(pmc->mca_tomb, pmc->idev), - lockdep_is_held(&im->idev->mc_lock)); - rcu_assign_pointer(pmc->mca_tomb, tomb); - - sources =3D rcu_replace_pointer(im->mca_sources, - mc_dereference(pmc->mca_sources, pmc->idev), - lockdep_is_held(&im->idev->mc_lock)); - rcu_assign_pointer(pmc->mca_sources, sources); - for_each_psf_mclock(im, psf) - psf->sf_crcount =3D idev->mc_qrv; - } else { - im->mca_crcount =3D idev->mc_qrv; - } - in6_dev_put(pmc->idev); - ip6_mc_clear_src(pmc); - kfree_rcu(pmc, rcu); + if (!pmc) + return; + if (pmc_prev) + rcu_assign_pointer(pmc_prev->next, pmc->next); + else + rcu_assign_pointer(idev->mc_tomb, pmc->next); + + im->idev =3D pmc->idev; + if (im->mca_sfmode =3D=3D MCAST_INCLUDE) { + tomb =3D rcu_replace_pointer(im->mca_tomb, + mc_dereference(pmc->mca_tomb, pmc->idev), + lockdep_is_held(&im->idev->mc_lock)); + rcu_assign_pointer(pmc->mca_tomb, tomb); + + sources =3D rcu_replace_pointer(im->mca_sources, + mc_dereference(pmc->mca_sources, pmc->idev), + lockdep_is_held(&im->idev->mc_lock)); + rcu_assign_pointer(pmc->mca_sources, sources); + for_each_psf_mclock(im, psf) + psf->sf_crcount =3D idev->mc_qrv; + } else { + im->mca_crcount =3D idev->mc_qrv; } + in6_dev_put(pmc->idev); + ip6_mc_clear_src(pmc); + kfree_rcu(pmc, rcu); } =20 static void mld_clear_delrec(struct inet6_dev *idev) --=20 2.34.1