From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794590211; b=zE5aW4wQOND8mv7e09XGApKv1zy0ZJO+pwqsxT+eXkv99qSp2oANezg08DBHA8MkYEoc hEKceRwPo+Qp4CRJnsjaN8yYUQy6ow1VDesC5pxqQyx/Lh0su3CAqcTm2kUrlkiRRPj1J t9rR1ZFbtcMTZuWOZBcCaYfRUpzX7pDiIsz5Ugy5LoGH7RH5ulNLjKI8wVh3VPvYq/oPz 380u7+sMuTmgzB4ZDD7yrFa2X5BACHJUFcXmmYz4jGrxZzt8GmihSllo+jR00KRhXttif pQRrGBJq3SUeLmFEGzz5ledP/Yf44o2buZsN6Hlhj+RtXaQkOpiLx7DEO1g1BM2VXBw== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794590211; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Transfer-Encoding; bh=pJ/Rzi1mt4/6bQ/PWrme+rTsbUgeb/AIR8gOLJaxKxE=; b=K6NH5WjT0RfutK+kf3t7Xe/8WGfSw19eLs5ZalsV9QFxycEUd8NshdYvPNb9zuAecUkH yulX7Vk1BU/EQ9BYliolbSmIJ87Ii1SgCRIULynjTghl4q7V1Ya+nxd6GBEhlnwRIG1KY VJFD6pUwx80TWAv7yxnzGZViCfTRPxoO56OdkV+IQGupg6EwjudQBKASMo7yItLKlYD7d vOyuqIjwjXlup8I8SUq1avbs5q2KzfZV4Rqy/WEkIJljbyj+UDv/f9dj59CdznVH+Zhvv y1CroztborbpIywllmCKXDzIPGTvOA13AA124vRQQqjw+2y7xTkPgA2zp7qvqGsJs2A== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=eau+LoXA; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id F3C9A606A8B8; Fri, 13 Nov 2026 17:16:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=eau+LoXA Received: by smtp.kernel.org (Postfix) with ESMTPSA id A05811F000C5; Fri, 13 Nov 2026 17:16:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1794590210; bh=pJ/Rzi1mt4/6bQ/PWrme+rTsbUgeb/AIR8gOLJaxKxE=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=eau+LoXA73YVCmNg2GGPQG1xWsE7CUF84o6wd50QMwvbfg6pdP6mJw5DVL+dsg3r9 AYMrv1yYbTwvY0LgfVmNEjMQIgwufoZpGt0PJGTyHK77uHN+3+iJYMpYRCbhmQd5P2 EBIHD9ZL6mmxqmnO0tjCzlPsxiNCnwO7+WX7EpS4= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Sven Eckelmann , Sasha Levin Subject: [PATCH 6.18 213/686] batman-adv: fix skb leak when hard_iface is being released Date: Fri, 13 Nov 2026 10:45:46 -0500 Message-ID: <20261113153828.253759140@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261113153820.902362109@linuxfoundation.org> References: <20261113153820.902362109@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: patches@lists.linux.dev List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Sven Eckelmann [ Upstream commit 522e4aece2e96cacbb8a6ae1eec0d4c0dd6f4fed ] batadv_batman_skb_recv() owns the skb it is given. When the hard_iface refcount already dropped to zero, the function jumped to err_out, which only returned NET_RX_DROP and skipped the kfree_skb() under err_free. To avoid a leak, free the skb before returning in this case. Cc: stable@vger.kernel.org Fixes: 4fe56e60ac1b ("batman-adv: Check hard_iface refcnt when receiving skb") Signed-off-by: Sven Eckelmann Signed-off-by: Sasha Levin --- net/batman-adv/main.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/net/batman-adv/main.c b/net/batman-adv/main.c index f1b41078835b6..870754d1d86f9 100644 --- a/net/batman-adv/main.c +++ b/net/batman-adv/main.c @@ -427,8 +427,10 @@ int batadv_batman_skb_recv(struct sk_buff *skb, struct net_device *dev, * shut down otherwise the packet may trigger de-reference errors * further down in the receive path. */ - if (!kref_get_unless_zero(&hard_iface->refcount)) - goto err_out; + if (!kref_get_unless_zero(&hard_iface->refcount)) { + kfree_skb(skb); + return NET_RX_DROP; + } skb = skb_share_check(skb, GFP_ATOMIC); @@ -487,7 +489,6 @@ int batadv_batman_skb_recv(struct sk_buff *skb, struct net_device *dev, kfree_skb(skb); err_put: batadv_hardif_put(hard_iface); -err_out: return NET_RX_DROP; } -- 2.53.0