From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 65B4324468C; Sat, 30 May 2026 18:50:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780167053; cv=none; b=NZXw5f6C65VxpcWRFq8CFVa+Q1A5cOS7y24uEl6vZ3McTBBPFdpcsWCV+B+Q2bHcvg769Cx5yJpwlS7OtSP0tS3Y7VXhzDGiqP+PsJHdyjt8Vc/VMnAVxo+2/NOmpuuErAK0zCcHaqQ9F4i9Qj9BNYvJA2qgwlbFPi4fnpRkL1U= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780167053; c=relaxed/simple; bh=HWoywexH/JuTWNpmvrlqGLYy33ZadZQFlUK7osRdqPQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=uoWI1wAcy7ZsCpvrdpX2Yo8kl/LYTtPlwYYFGwhZehzie1SbmnV2UpbKnO/yOzH/d2wvB5881psPaDNJYITAtnxe6IL/+zyP8lbkp4F3JzBB5/SrkSZV878gDrTqmG4xCZMLrm4VHG6HOysC6g0CMTEug3kPQwp1x7gTJIac/NE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=ZoIFXLtH; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="ZoIFXLtH" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A0EAF1F00893; Sat, 30 May 2026 18:50:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1780167051; bh=s5Y8FgEVDzeXX/vRMbiFuQ/hTKzf03qiwLVTb1otq/g=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=ZoIFXLtHesUjRjqc+p29N1OmhAfbFvRR2dxuGDTeQUwJUyXd4xnB2l/fyrKncO+Vf Wn2/v7MWU6oE5HHk8zlgyf6nmA229gFBGJJy0GIhBCemMFwyVaBg3MdkLCNbCybLb6 bV27+cn/FsmnRaECH4uRyEfd/vOO/hBX5h9rPUMc= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, stable@kernel.org, =?UTF-8?q?Linus=20L=C3=BCssing?= , Sven Eckelmann Subject: [PATCH 5.10 550/589] batman-adv: mcast: fix use-after-free in orig_node RCU release Date: Sat, 30 May 2026 18:07:11 +0200 Message-ID: <20260530160239.122702468@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260530160224.570625122@linuxfoundation.org> References: <20260530160224.570625122@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 5.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Sven Eckelmann commit 20c2d6a20ca936f5aaa6dd40f73f262ac45c87cc upstream. batadv_mcast_purge_orig() removes entries from RCU-protected hlists but does not wait for an RCU grace period before returning. Concurrent RCU readers may still accesses references to those entries at the point of removal. RCU-protected readers trying to operate on entries like orig->mcast_want_all_ipv6_node will then access already freed memory. Fix this by moving batadv_mcast_purge_orig() to batadv_orig_node_release(), just before the call_rcu() invocation. This ensures RCU readers that were active at purge time have drained before the orig_node memory is reclaimed. Cc: stable@kernel.org Fixes: ab49886e3da7 ("batman-adv: Add IPv4 link-local/IPv6-ll-all-nodes multicast support") Acked-by: Linus Lüssing Signed-off-by: Sven Eckelmann Signed-off-by: Greg Kroah-Hartman --- net/batman-adv/originator.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/net/batman-adv/originator.c +++ b/net/batman-adv/originator.c @@ -866,8 +866,6 @@ static void batadv_orig_node_free_rcu(st orig_node = container_of(rcu, struct batadv_orig_node, rcu); - batadv_mcast_purge_orig(orig_node); - batadv_frag_purge_orig(orig_node, NULL); kfree(orig_node->tt_buff); @@ -922,6 +920,8 @@ void batadv_orig_node_release(struct kre /* Free nc_nodes */ batadv_nc_purge_orig(orig_node->bat_priv, orig_node, NULL); + batadv_mcast_purge_orig(orig_node); + call_rcu(&orig_node->rcu, batadv_orig_node_free_rcu); }