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=1794591093; b=NzviLIozIQ2ZMFrkldoglUnExqXbYjsPDbXprkOBzhPebITxZ+/H0o32+yolx5U3caYQ +xIceegTV6yZCO5BgdWDfTviLRwXS85yivKDtOD02VehQmKNmyNGOay/r1PUO24sJzkK+ dpyrXSSSRThqyzEv40Zr+kEwghPy/y+e1xjy4/VGSaOq2ylNJPPnj7ozUaHVJIeI6eDe/ u339PguySICNFkGtIs0qk5uqmg17MGVISlZJY8csmOG6snJtGEx1D7pO1X3dGWkXvjA9u gtXNoOY0ppCSIt+ny/n+ucK8FP+ZPwVd5qbnPpKqI7Rc699imtf8uM6D3+XbD7gLJwA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794591093; 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=YsgVosuv/oB79/fuzBRqf3g3OqX7vDsNfJ+CDNCW1a0=; b=Nlaylef73mALDEtHQEYinTCoSevNrUkGrzMRcb0XrKclAzEYUGcwS09YI1MTx54Oexdf xTcmIvPV3kW/SyjSjtVhEEuHreJOBk1DdeJcdfgBqWfjd3F6RoLHHHHkkeIWCauJMAHBx IkFonJDEdT2M+9/2tPzDwmANTt6Vd2svwoqY9ueYPr9qsd5gP6+Zx6ogRgOCkOwpPNaT5 4c7rq33+MfKeIyTzdDV8Qy5sqW0SFW2jAldk6PpVhKNURwMko527kywuY48TuzLbfwfYG AJiJrf1qF8M0ye/LHfHLqMf3nQj5LcaD8GWJgjR0TNBiGNzREsiT+KERDyAQEutOJZw== 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="CcI/04GT"; 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 CF72D606A880; Fri, 13 Nov 2026 17:31:33 +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=CcI/04GT Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7B70A1F000C4; Fri, 13 Nov 2026 17:31:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1794591093; bh=YsgVosuv/oB79/fuzBRqf3g3OqX7vDsNfJ+CDNCW1a0=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=CcI/04GTcFc7TRZWB613CQKBtOeUVrjLj7lqsGX1SYHqHMnrCcKhPBywbyU7bBGul /BLVUsUNStsiFToax1ZtZXdHbv1Dba09QrbVrUxLi8NFoRI3vOeu/XGRiM+81K3TRE Y0eABI8+/ps3XNnfC/ThpGQxmpk7DFifl8daVMGE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Sven Eckelmann , Sasha Levin Subject: [PATCH 6.12 197/670] batman-adv: fix skb leak when hard_iface is being released Date: Fri, 13 Nov 2026 10:46:01 -0500 Message-ID: <20261113153818.660546586@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261113153811.177190860@linuxfoundation.org> References: <20261113153811.177190860@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: stable@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-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 8091619981c0d..55055d3290e74 100644 --- a/net/batman-adv/main.c +++ b/net/batman-adv/main.c @@ -449,8 +449,10 @@ 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); @@ -509,7 +511,6 @@ 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