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 1A9A62931C5 for ; Thu, 16 Jul 2026 12:47:05 +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=1784206027; cv=none; b=C5vWwzyPu0uS+UuWY2cJPqAV7DtB1Kkg962dBFZ1hsRrUj43SuckfkD3Kt4EKoYjhKL60PQSGjdBkGo4XrdbArFiHcGCt7FjDoqyvPmASGjKNeObHtnqHzAwJtraENRaY3MExzwnfJgGnCNfErBIAZRFFNGIW7HDmiMtX995jIQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784206027; c=relaxed/simple; bh=TXpl6XrTo2u1RMC9H/TQc0G/a4g6RohRr0AClW0qIdg=; h=Subject:To:Cc:From:Date:Message-ID:MIME-Version:Content-Type; b=uPM9UKpePSvgPj7jW+REP0FsOhpPOzLrixz18TBREBm61IMGbrRmqGiQW1c53QER5bUW7gd7mw/i5WZ1MOUr9AvS3P+xkmBTz2GK3Ehte6m2jy1T5CVfhPuTGNSPy4r/erTI2fVggT55QmyazEeIJFVML3CmkmNOneC3e1CvL90= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=2u5LhBsG; 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="2u5LhBsG" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 178FF1F000E9; Thu, 16 Jul 2026 12:47:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1784206025; bh=Ban+JBJVplb3rHDbfDuVnKW+ypfuwRuKTvf4sDUh664=; h=Subject:To:Cc:From:Date; b=2u5LhBsGEHG1B8+iaFhG3Z7dT1WfRk+vVOxVMT6Gf9LfQ55rq0mCpNSEAkTYt+Huk CdlPr0zCSpWYqfUeE6VUIv9HlXD82sTW2ioKRmqNLpkUAVDPFopjfJVYlOe38AS+kY cswwD37Ja0Pe8wo7Jp9kvY1IDBZxm0Dgv/zsE/DE= Subject: FAILED: patch "[PATCH] RDMA/rtrs-srv: Bound RDMA-Write length to chunk size in" failed to apply to 5.10-stable tree To: whi4ed0g@gmail.com,danisjiang@gmail.com,haris.iqbal@ionos.com,jgg@nvidia.com Cc: From: Date: Thu, 16 Jul 2026 14:46:58 +0200 Message-ID: <2026071658-gone-jawless-67b1@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit The patch below does not apply to the 5.10-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.10.y git checkout FETCH_HEAD git cherry-pick -x 963af8d97a8c6a117134a8d0db1415e0489200b1 # git commit -s git send-email --to '' --in-reply-to '2026071658-gone-jawless-67b1@gregkh' --subject-prefix 'PATCH 5.10.y' 'HEAD^..' Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 963af8d97a8c6a117134a8d0db1415e0489200b1 Mon Sep 17 00:00:00 2001 From: Zhenhao Wan Date: Fri, 12 Jun 2026 01:15:54 +0800 Subject: [PATCH] RDMA/rtrs-srv: Bound RDMA-Write length to chunk size in rdma_write_sg When the server answers an RTRS READ, rdma_write_sg() builds the source scatter/gather entry for the IB_WR_RDMA_WRITE that returns data to the peer. Its length is taken directly from the wire descriptor: plist->length = le32_to_cpu(id->rd_msg->desc[0].len); rd_msg points into the chunk buffer that the remote peer filled via RDMA-WRITE-WITH-IMM (rtrs_srv_rdma_done() -> process_io_req() -> process_read()), so desc[0].len is attacker-controlled and, before this change, was only rejected when zero. The source address is the fixed chunk start (dma_addr[msg_id]) and the source lkey is the PD-wide local_dma_lkey, which is not tied to the chunk's MR mapping, so the verbs layer does not constrain the transfer length to max_chunk_size. msg_id and off are bounded against queue_depth and max_chunk_size in rtrs_srv_rdma_done(), but desc[0].len is a separate field that was not checked against the chunk size. A peer that advertises desc[0].len larger than max_chunk_size can make the posted RDMA write read past the chunk's mapped region. The resulting behaviour depends on the IOMMU configuration: with no IOMMU or in passthrough mode the read may extend into memory adjacent to the chunk and be returned to the peer, which can disclose host memory; with a translating IOMMU the out-of-range access is expected to fault and abort the connection. In either case the transfer exceeds what the protocol permits and is driven by a remote peer. Reject a descriptor length above max_chunk_size, mirroring the existing off >= max_chunk_size bound in rtrs_srv_rdma_done(). Legitimate clients do not exceed it: the client sets desc[0].len to its MR length, which is capped at the negotiated max_io_size (max_chunk_size - MAX_HDR_SIZE). Fixes: 9cb837480424 ("RDMA/rtrs: server: main functionality") Link: https://patch.msgid.link/r/20260612-master-v1-1-70cde5c6fdc9@gmail.com Reported-by: Yuhao Jiang Cc: stable@vger.kernel.org Signed-off-by: Zhenhao Wan Reviewed-by: Md Haris Iqbal Signed-off-by: Jason Gunthorpe diff --git a/drivers/infiniband/ulp/rtrs/rtrs-srv.c b/drivers/infiniband/ulp/rtrs/rtrs-srv.c index f2fd80c8a044..7d8e4422cc57 100644 --- a/drivers/infiniband/ulp/rtrs/rtrs-srv.c +++ b/drivers/infiniband/ulp/rtrs/rtrs-srv.c @@ -225,8 +225,9 @@ static int rdma_write_sg(struct rtrs_srv_op *id) /* WR will fail with length error * if this is 0 */ - if (plist->length == 0) { - rtrs_err(s, "Invalid RDMA-Write sg list length 0\n"); + if (plist->length == 0 || plist->length > max_chunk_size) { + rtrs_err(s, "Invalid RDMA-Write sg list length %u\n", + plist->length); return -EINVAL; }