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 1DEFC404BC8; Fri, 7 Aug 2026 14:50:04 +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=1786114205; cv=none; b=BI9ISyH48nEyj7XS03q9Wu25/4Cicb/uXdVh5H+ALfgGmu5ilYP1Hh5dOkr+B1IuUEH2xkKNOHWLgI5vNMuCzCrF8g5iYFBdfPjlaRjNCdVSvETCsrtiwYzcWjEBVEwmpcmd+NtDAx27JmEpsqrR5KJHkQF5WIlNZ3iT9gcxqD4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786114205; c=relaxed/simple; bh=J9lgRUYgbr8ZNdbk2/vjXTlCEL3tpHIpuLxCSifD2Bk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=a3GNpW7RFGtG7WnshzgElGxeyC2noaGhUm3Jm5L4IpWaPiPUllSN4hhKgSIWD8yrGRJhstfR2OhzDElkVDD2DAfNy2+LxJp7C27fS9E6R4vMglOR1fBZ8RI95/WusOFSfmGQ+mFBkyNOATQ+nfn74zaGvPhAlCuygCGGG3nyMEw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=1rAj2ZwG; 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="1rAj2ZwG" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A42971F000E9; Fri, 7 Aug 2026 14:50:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1786114204; bh=u6WZh/I0nvYle/aIblYDlwQP7biibFlZQdASMFCqlUs=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=1rAj2ZwGNW4S+rYUGA8pNvNo5xA0IUEu9Bkg0+64+2LwjRqoXay4d2sopqipAhdIl jXfFsTl3iwFWTeBT34oNjN/LzgNcdrz2RFoeqCcp2ZFCejCZbOi0828Vvf5JNT2792 kdTJWLhd1DIdO6tu1Q7GDNqdW7daiiFacmxX2oh8= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Vega , Zhiling Zou , Ren Wei , Nikolay Aleksandrov , Jakub Kicinski Subject: [PATCH 6.12 182/337] net: bridge: stop fast-leave after deleting a port group Date: Fri, 7 Aug 2026 16:36:25 +0200 Message-ID: <20260807143422.504124029@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260807143418.516897842@linuxfoundation.org> References: <20260807143418.516897842@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-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Zhiling Zou commit a39789f211b8a4125f0c70e05b30cf715f4f187d upstream. br_multicast_leave_group() iterates mp->ports with pp = &p->next in its fast-leave path. After br_multicast_del_pg() removes p, continuing the loop advances pp through the deleted entry. If multicast-to-unicast was enabled, the bridge can hold multiple port groups for the same port and group with different source MAC addresses. Once multicast-to-unicast is disabled, br_port_group_equal() matches those entries by port only. A fast leave can then delete one entry and continue from its stale next pointer, leaving mp->ports pointing at a deleted port group. Fast leave only needs to remove one matching port group. Break after br_multicast_del_pg() so the loop stops before dereferencing the removed entry. Fixes: 6db6f0eae605 ("bridge: multicast to unicast") Cc: stable@vger.kernel.org Reported-by: Vega Signed-off-by: Zhiling Zou Signed-off-by: Ren Wei Acked-by: Nikolay Aleksandrov Link: https://patch.msgid.link/1cf0898872ef7c72d5f4c0304414a192c6dac591.1784707712.git.zhilinz@nebusec.ai Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman --- net/bridge/br_multicast.c | 1 + 1 file changed, 1 insertion(+) --- a/net/bridge/br_multicast.c +++ b/net/bridge/br_multicast.c @@ -3685,6 +3685,7 @@ br_multicast_leave_group(struct net_brid p->flags |= MDB_PG_FLAGS_FAST_LEAVE; br_multicast_del_pg(mp, p, pp); + break; } goto out; }