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 A18BD43802D; Mon, 17 Aug 2026 14:46:21 +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=1786977982; cv=none; b=E1vSIjjcRuNgkT+/ZL2XlnFi0m+MpK4sXPqlwhlTCVbZaxrLJnBWA8eA8QA+lry7Kk12TZMR43ZuSEXAn6ItUyXdrAaAyP7bE09laLf32uLZC/xgrhnb/tPCJcRJlD4JWlWaJAR6fTuFoP9hxPUuJGWWVzjjvqDCNJBdcqMgId8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786977982; c=relaxed/simple; bh=JaguDEymoFtCK7UWqV1KlqwN3YHdCmUhvDWltBlDCIM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=jYUuOdbXnKw4sKqyxCd5ue1Si1kh7vd1Fwxe8aD2hqKtFZ65dfsbkCcjjbxnKgGwmRPM8O2t/mTO4fb7UoASKPd0p1/fxiw0/He0panuI7owJBx4f+1GnKooefBme75kqBWdHttsSMxAYk4nkVZjcDofwE3896EhFCiWzirBW6E= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=z4FUleKV; 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="z4FUleKV" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 059811F00A3A; Mon, 17 Aug 2026 14:46:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1786977981; bh=32ZywOErqoZ8o40YnF3htcwVuB0PZGoe6RfEGbfNTDo=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=z4FUleKVoiQnDcDpEvkrYSyKzorehUl4jGJC+ArNinZsUpHh1kXKfgsAtt7Ri7iDm /fwpeXvLFwUI8ximRNWaonmbYnHWbwoJjSgYixeGAdCJCnBHMAapI7c/Wtlj2D7uP8 yW52AjSbUIDbCRBV+sMjVix8/S8/pJiZIcAd7Ugk= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Daniele Linguaglossa , Xin Long , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.12 060/181] sctp: clear control chunk transport if it is being removed Date: Mon, 17 Aug 2026 15:32:34 +0200 Message-ID: <20260817132537.782607208@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260817132535.394764707@linuxfoundation.org> References: <20260817132535.394764707@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: Xin Long [ Upstream commit c9158ceaf27780ef64534ad72f44ffde3f8ccc49 ] sctp_make_heartbeat_ack() caches the destination transport in chunk->transport without taking a reference. When src_out_of_asoc_ok is enabled, the HEARTBEAT ACK may remain queued on control_chunk_list instead of being transmitted immediately. If the peer transport is removed while the chunk is still queued, sctp_assoc_rm_peer() drops the transport and schedules it for RCU freeing, but only clears cached transport pointers in out_chunk_list. The queued control chunk therefore retains a dangling transport pointer. Once an ASCONF_ACK clears the suppression and the queued control chunk is transmitted, SCTP dereferences the stale transport pointer, leading to a use-after-free. Fix this by also clearing chunk->transport for queued control chunks in control_chunk_list when removing the transport. Fixes: 8a07eb0a50ae ("sctp: Add ASCONF operation on the single-homed host") Reported-by: Daniele Linguaglossa Signed-off-by: Xin Long Link: https://patch.msgid.link/7e1168cb722132152a29d47e5eafaeac4a3bf6f3.1785943120.git.lucien.xin@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/sctp/associola.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/net/sctp/associola.c b/net/sctp/associola.c index 44f06c5f1f256..ebdc48be47813 100644 --- a/net/sctp/associola.c +++ b/net/sctp/associola.c @@ -573,6 +573,10 @@ void sctp_assoc_rm_peer(struct sctp_association *asoc, if (ch->transport == peer) ch->transport = NULL; + list_for_each_entry(ch, &asoc->outqueue.control_chunk_list, list) + if (ch->transport == peer) + ch->transport = NULL; + asoc->peer.transport_count--; sctp_ulpevent_notify_peer_addr_change(peer, SCTP_ADDR_REMOVED, 0); -- 2.53.0