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 CBD81368276; Fri, 7 Aug 2026 15:10:33 +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=1786115435; cv=none; b=KXVs3XKIEUqQJaWaR+j0ctDgejIuztjHAsFoJMIFqhTHTwlXkKVeg5PrT7mkLVn6v/h58+oCx7vgaKxqnr8niBy4nMxALw/8IFXJqhng2w1DUCFnc3Vy3KNfuBTJMQYyMzdg/Z/KjGpMwXT1B8b/tcyizAw/WaFWrjby0UDcyD0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786115435; c=relaxed/simple; bh=l1NnFUXRRXbrMKqkMFQm1pYLO8c5Km94aU0gS2e58bo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=hADCU6b6gzdxblroW3aY4Ixu4Lik9Hfj5/fYe5bbxVI4a1tfaDpzoVX02HKE/4GXEM1b/7u6ZxM/WxxfWGuPAdh8EmtdVlKJiaf89huOBWVkvBwa0E3O0bQIVQJ6Z3uYEdb1ahggaGba3+OoKBese719m98sXA//ZJLQkWkXVhc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=Jk/E9SKc; 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="Jk/E9SKc" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 15F7B1F000E9; Fri, 7 Aug 2026 15:10:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1786115433; bh=QkPmrilpibC/xGu3lduWJVOBu4Q2IBZGYPBft3rIXUI=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=Jk/E9SKc68S1FyZyWB+CSpuvs6CTplkFzBjeqc+RQ5Bki2OXXUiAZiPovEyXbA+C1 dAOsA283488nEijUmS+Iud+U7g8OUrFR/kf1FoTt86XQHXfbjmvWzPno0biHbc47af MUoQWzonEQOhwes+16OSl4E4qVkubx2nrKSLl1OM= 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 6.18 238/396] net: bridge: stop fast-leave after deleting a port group Date: Fri, 7 Aug 2026 16:36:38 +0200 Message-ID: <20260807143429.391078745@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260807143424.272339768@linuxfoundation.org> References: <20260807143424.272339768@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 6.18-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 @@ -3686,6 +3686,7 @@ br_multicast_leave_group(struct net_brid p->flags |= MDB_PG_FLAGS_FAST_LEAVE; br_multicast_del_pg(mp, p, pp); + break; } goto out; }