From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx1.white.stw.pengutronix.de (mx1.white.stw.pengutronix.de [185.203.200.13]) (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 827B33FBB5E; Wed, 26 Aug 2026 12:10:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.203.200.13 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787746252; cv=none; b=Vcy2nJKEwsP16ir8RUQjKhPSAB3tXgpw/PuqTskEjwqyE+6oTPuX9nKHquv/MLJtDm797lTYN3qAqE6cl92zj0jts1mceLObN1E6bTryBCKwYv4QA7tgm9fvdiAcY32OvLsATm6sNJQtMpjqurnsIxeGW2rnD54IEGzpnFUnLGg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787746252; c=relaxed/simple; bh=QvaIjbYrpB4EGXvXex/5tmRypBqPdkpZunXBsbNiKCI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=SPCRTsWgUlxkJq2IQBYY30LbhYOwgYeuLpemEuN17CIiicbpHWLXndsVVzCylc6WKpypTtHzqNING+S7/OOXGhKO4VXExjYEZCzCxeFUs8ICFtzG4n6hLAxq9RVDpCnnGTuehj8+8WVgzYLOagrJXbCpoVHAQ+CgDncVxQq0ruc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=pengutronix.de; spf=pass smtp.mailfrom=pengutronix.de; arc=none smtp.client-ip=185.203.200.13 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=pengutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=pengutronix.de Received: from drehscheibe.grey.stw.pengutronix.de (drehscheibe.grey.stw.pengutronix.de [IPv6:2a0a:edc0:0:c01:1d::a2]) (Authenticated sender: relay-from-drehscheibe.grey.stw.pengutronix.de) by mx1.white.stw.pengutronix.de (Postfix) with ESMTPSA id 0667B20227A; Wed, 26 Aug 2026 14:10:39 +0200 (CEST) Received: from moin.white.stw.pengutronix.de ([2a0a:edc0:0:b01:1d::7b] helo=bjornoya.blackshift.org) by drehscheibe.grey.stw.pengutronix.de with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1wzCSk-003R99-2h; Wed, 26 Aug 2026 14:10:38 +0200 Received: from blackshift.org (p4ffb23c7.dip0.t-ipconnect.de [79.251.35.199]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519MLKEM768 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) (Authenticated sender: mkl-all@blackshift.org) by smtp.blackshift.org (Postfix) with ESMTPSA id 94A2758CCFF; Wed, 26 Aug 2026 12:10:38 +0000 (UTC) From: Marc Kleine-Budde To: netdev@vger.kernel.org Cc: davem@davemloft.net, kuba@kernel.org, linux-can@vger.kernel.org, kernel@pengutronix.de, Cunhao Lu <1579567540@qq.com>, Marc Kleine-Budde Subject: [PATCH net 08/14] can: skb: make echo skb freeing safe in any IRQ context Date: Wed, 26 Aug 2026 14:02:18 +0200 Message-ID: <20260826121036.2706424-9-mkl@pengutronix.de> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260826121036.2706424-1-mkl@pengutronix.de> References: <20260826121036.2706424-1-mkl@pengutronix.de> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Cunhao Lu <1579567540@qq.com> can_put_echo_skb() can be called with hardware interrupts disabled. Its direct drop paths use kfree_skb(), while can_create_echo_skb() uses kfree_skb() when cloning fails and consume_skb() after a successful clone. None of these helpers is safe in every IRQ context. Use dev_kfree_skb_any() for all drop paths and dev_consume_skb_any() when consuming a successfully cloned skb. This preserves the respective skb drop and consumed semantics regardless of the caller IRQ context. Signed-off-by: Cunhao Lu <1579567540@qq.com> Link: https://patch.msgid.link/tencent_E84809CF236D0137885E7E4E4D58340B3208@qq.com Signed-off-by: Marc Kleine-Budde --- drivers/net/can/dev/skb.c | 4 ++-- include/linux/can/skb.h | 4 ++-- 2 files changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/net/can/dev/skb.c b/drivers/net/can/dev/skb.c index 4f7a189de265..0ed8057a3cb2 100644 --- a/drivers/net/can/dev/skb.c +++ b/drivers/net/can/dev/skb.c @@ -63,7 +63,7 @@ int can_put_echo_skb(struct sk_buff *skb, struct net_device *dev, (skb->protocol != htons(ETH_P_CAN) && skb->protocol != htons(ETH_P_CANFD) && skb->protocol != htons(ETH_P_CANXL))) { - kfree_skb(skb); + dev_kfree_skb_any(skb); return 0; } @@ -91,7 +91,7 @@ int can_put_echo_skb(struct sk_buff *skb, struct net_device *dev, } else { /* locking problem with netif_stop_queue() ?? */ netdev_err(dev, "%s: BUG! echo_skb %d is occupied!\n", __func__, idx); - kfree_skb(skb); + dev_kfree_skb_any(skb); return -EBUSY; } diff --git a/include/linux/can/skb.h b/include/linux/can/skb.h index a70a02967071..78c5870e2f9a 100644 --- a/include/linux/can/skb.h +++ b/include/linux/can/skb.h @@ -76,12 +76,12 @@ static inline struct sk_buff *can_create_echo_skb(struct sk_buff *skb) nskb = skb_clone(skb, GFP_ATOMIC); if (unlikely(!nskb)) { - kfree_skb(skb); + dev_kfree_skb_any(skb); return NULL; } can_skb_set_owner(nskb, skb->sk); - consume_skb(skb); + dev_consume_skb_any(skb); return nskb; } -- 2.53.0