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 1DE873F20FA; Wed, 20 May 2026 17:52:41 +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=1779299562; cv=none; b=IATUeoJeNed8BWZrm5eQfmuN2BhAOvCaSQMNWn7AcbVnTXbIM0c50Q8q7uWH8lRmvhJTkuwnh1mCFcOqaqGRcwo7llatBTQJMRygoY1fDCbqvowokqIRX+XXcdJOG37VK/EQoxsZCCqBeje0CtNaddTZ6rKFr3LMn4fFD/b/klE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779299562; c=relaxed/simple; bh=/NWStgR0mRce+JrtD7kDnry89NhrNXEbNRXc8tBuE/Y=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=oA/lvQU0P20AI2Mw9Oe+ajzyoa+CdYS2lo1EZHVgdvvYct9i2XLq4cdsYh0XqCQa7bCNr5V6t6AVLD0B7G9v38BZHoxnSgFro0UZy9PrGPb683cj8WiDoYJzfklXOofrINjEMB3THbukRIjeX/tY4XrPAkV/fEjXRZxuLSp5yps= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=voWEzj8I; 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="voWEzj8I" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 83A0F1F000E9; Wed, 20 May 2026 17:52:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1779299561; bh=zm3g2lrO7xn9cATOxLQ+q5/oh+ipVxSQ2Jb39j+qJ5Y=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=voWEzj8ImuEFxLLOjNAJPBaOwPJnAagdEEIswh/l9VUTYqHps5WiOPoPIjTua5Whi Lr8afrI0kQI8+hlUhdxncAVVk4yLWDKyZ3PTQ725Tr6JPw1uB8gS3LtYi9EDvzSvyy xRwbP248Wus4tFO1PKBnU9zgZSRGmjFAboEg5TIk= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Xin Long , Marcelo Ricardo Leitner , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.18 819/957] sctp: discard stale INIT after handshake completion Date: Wed, 20 May 2026 18:21:42 +0200 Message-ID: <20260520162152.328107752@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260520162134.554764788@linuxfoundation.org> References: <20260520162134.554764788@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Xin Long [ Upstream commit 8a92cb475ca90d84db769e4d4383e631ace0d6e5 ] After an association reaches ESTABLISHED, the peer’s init_tag is already known from the handshake. Any subsequent INIT with the same init_tag is not a valid restart, but a delayed or duplicate INIT. Drop such INIT chunks in sctp_sf_do_unexpected_init() instead of processing them as new association attempts. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Xin Long Acked-by: Marcelo Ricardo Leitner Link: https://patch.msgid.link/5788c76c1ee122a3ed00189e88dcf9df1fba226c.1777214801.git.lucien.xin@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/sctp/sm_statefuns.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/net/sctp/sm_statefuns.c b/net/sctp/sm_statefuns.c index 7b823d7591419..8e89a870780c4 100644 --- a/net/sctp/sm_statefuns.c +++ b/net/sctp/sm_statefuns.c @@ -1556,6 +1556,12 @@ static enum sctp_disposition sctp_sf_do_unexpected_init( /* Tag the variable length parameters. */ chunk->param_hdr.v = skb_pull(chunk->skb, sizeof(struct sctp_inithdr)); + if (asoc->state >= SCTP_STATE_ESTABLISHED) { + /* Discard INIT matching peer vtag after handshake completion (stale INIT). */ + if (ntohl(chunk->subh.init_hdr->init_tag) == asoc->peer.i.init_tag) + return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); + } + /* Verify the INIT chunk before processing it. */ err_chunk = NULL; if (!sctp_verify_init(net, ep, asoc, chunk->chunk_hdr->type, -- 2.53.0