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 855BC3D669D for ; Wed, 9 Sep 2026 09:26:10 +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=1788945971; cv=none; b=obZ6SIAPQPE9m5Lu9MaM/UVYqh1J7vafNUV5oMDlwihZEYj7mux/NSxOu/oxuFQIhJMR1jLNvvDlada89TFjMc7tBV0gJ4dakXKFjwPmglMFbzk1C8UqfBHeUK2eQeT4GEB4D1baaa9tOzWPVrtyTGiD9cEP6Jl2Y42DzUEZ6UU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788945971; c=relaxed/simple; bh=IWJpRKhaCb2+epJ7n+DEv4xLmao7oJUoLK3MTjVeD8A=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ii06nQf4GVE4DJbEK6KoT8/HMLLq2J5rapXHsqeNXgGB3ML8ib8Fae/618WKhcbRrBKcyYb73tsnnGlor1owMsGIlxFXQ2JIuJ669ITHmr8YRR8Iig19D0JDopY6uaPHwAdad86ZQ/1ckqmxIlS9hzSyoyoQnervVghUKf/sPiY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=nef29YXL; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="nef29YXL" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E028D1F00A3F; Wed, 9 Sep 2026 09:26:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788945970; bh=LQNaC8C739AmcSDQHlUJ+4I92WR4iUOwKeWxzWkyrpw=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=nef29YXLbvg5PLk4uvIW4rY7yEugtntb2D5KqbEn2mzb9vyREtQmdWCul/J7ZBcwo 4UDhNXnNZYUIMXbH+IRdmxfM6z+EgL5iEeR9GpByyY+EztUGhAvUzoFYUyTBZvVUPz nj3HMqe9cbqxuhG3H2uUmcO6Ey1vnAw0+i5RllcwGe64LVe0rCV9oDOuHrX33CqGQT Otn/3q4wltEazIWLN9BdoSX3vC6BA1QS9UuE02u9dN4qqq+QTfjYNDv1TbtBuqnZeH V2j6MkTFRfBPOtMVdRN8pK/bxAtAHOaxhL7RXjdLPrPn8ExperyUvW7e32hbgafww2 ztF9ncJPdlw4Q== From: Sasha Levin To: stable@vger.kernel.org Cc: Chuck Lever , Jeff Layton , Sasha Levin Subject: [PATCH 6.6.y 4/4] svcrdma: Validate Read chunk positions before reconstruction Date: Wed, 9 Sep 2026 05:26:06 -0400 Message-ID: <20260909092606.1293505-4-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260909092606.1293505-1-sashal@kernel.org> References: <2026090309-wooing-reassign-9ecf@gregkh> <20260909092606.1293505-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Chuck Lever [ Upstream commit 3779b7b9e7d1c8ba4738f9d327de3b0288cefe9b ] The RPC/RDMA Read chunk position field is supplied by the remote client and stored verbatim in the parsed chunk list. xdr_count_read_segments() checks only 4-byte alignment; it never compares the position against the received inline body length. In the single-chunk path, svc_rdma_read_complete_one() splits the head and tail kvecs at ch_position. A position past the inline body underflows the tail length, exposing adjacent slab memory to the upper XDR decoder. In the multi-chunk path, svc_rdma_read_multiple_chunks() computes gap lengths between chunks as unsigned subtractions from ch_position. Overlapping Read chunks cause these subtractions to underflow. A final position past the inline body likewise underflows the trailing gap length. svc_rdma_copy_inline_range() then copies past the receive buffer into request pages that are returned to the client through the Reply channel. Bound inline-range copies in svc_rdma_copy_inline_range() against the decoded inline RPC body saved in rc_saved_arg. Reject a single Read chunk positioned beyond that body, and reject multi-chunk lists where accumulated read bytes exceed the next chunk's position. Apply the same position and overlap checks in the call-chunk interleaving path. Fixes: d96962e6d0e2 ("svcrdma: Use the new parsed chunk list when pulling Read chunks") Cc: stable@vger.kernel.org Acked-by: Jeff Layton Link: https://patch.msgid.link/20260526-rpc-kernel-bugs-v1-1-e251306ccca9@oracle.com Signed-off-by: Chuck Lever Signed-off-by: Sasha Levin --- net/sunrpc/xprtrdma/svc_rdma_rw.c | 38 ++++++++++++++++++++++++------- 1 file changed, 30 insertions(+), 8 deletions(-) diff --git a/net/sunrpc/xprtrdma/svc_rdma_rw.c b/net/sunrpc/xprtrdma/svc_rdma_rw.c index e2d64fffb9011..d69ead353b8fc 100644 --- a/net/sunrpc/xprtrdma/svc_rdma_rw.c +++ b/net/sunrpc/xprtrdma/svc_rdma_rw.c @@ -792,7 +792,7 @@ static int svc_rdma_build_read_chunk(struct svc_rqst *rqstp, * svc_rdma_copy_inline_range - Copy part of the inline content into pages * @rqstp: RPC transaction context * @head: context for ongoing I/O - * @offset: offset into the Receive buffer of region to copy + * @offset: offset into the inline content of region to copy * @remaining: length of region to copy * * Take a page at a time from rqstp->rq_pages and copy the inline @@ -809,9 +809,13 @@ static int svc_rdma_copy_inline_range(struct svc_rqst *rqstp, unsigned int offset, unsigned int remaining) { - unsigned char *dst, *src = head->rc_recv_buf; + unsigned char *dst, *src = head->rc_saved_arg.head[0].iov_base; + unsigned int inline_len = head->rc_saved_arg.head[0].iov_len; unsigned int page_no, numpages; + if (offset > inline_len || remaining > inline_len - offset) + return -EINVAL; + numpages = PAGE_ALIGN(head->rc_pageoff + remaining) >> PAGE_SHIFT; for (page_no = 0; page_no < numpages; page_no++) { unsigned int page_len; @@ -862,9 +866,10 @@ svc_rdma_read_multiple_chunks(struct svc_rqst *rqstp, { const struct svc_rdma_pcl *pcl = &head->rc_read_pcl; struct svc_rdma_chunk *chunk, *next; - unsigned int start, length; + unsigned int inline_len, start, length; int ret; + inline_len = head->rc_saved_arg.head[0].iov_len; start = 0; chunk = pcl_first_chunk(pcl); length = chunk->ch_position; @@ -882,6 +887,8 @@ svc_rdma_read_multiple_chunks(struct svc_rqst *rqstp, break; start += length; + if (head->rc_readbytes > next->ch_position) + return -EINVAL; length = next->ch_position - head->rc_readbytes; ret = svc_rdma_copy_inline_range(rqstp, head, start, length); if (ret < 0) @@ -889,7 +896,9 @@ svc_rdma_read_multiple_chunks(struct svc_rqst *rqstp, } start += length; - length = head->rc_byte_len - start; + if (start > inline_len) + return -EINVAL; + length = inline_len - start; return svc_rdma_copy_inline_range(rqstp, head, start, length); } @@ -914,8 +923,12 @@ svc_rdma_read_multiple_chunks(struct svc_rqst *rqstp, static int svc_rdma_read_data_item(struct svc_rqst *rqstp, struct svc_rdma_recv_ctxt *head) { - return svc_rdma_build_read_chunk(rqstp, head, - pcl_first_chunk(&head->rc_read_pcl)); + struct svc_rdma_chunk *chunk = pcl_first_chunk(&head->rc_read_pcl); + + if (chunk->ch_position > head->rc_saved_arg.head[0].iov_len) + return -EINVAL; + + return svc_rdma_build_read_chunk(rqstp, head, chunk); } /** @@ -984,14 +997,17 @@ static int svc_rdma_read_call_chunk(struct svc_rqst *rqstp, pcl_first_chunk(&head->rc_call_pcl); const struct svc_rdma_pcl *pcl = &head->rc_read_pcl; struct svc_rdma_chunk *chunk, *next; - unsigned int start, length; + unsigned int call_len, start, length; int ret; if (pcl_is_empty(pcl)) return svc_rdma_build_read_chunk(rqstp, head, call_chunk); + call_len = call_chunk->ch_length; start = 0; chunk = pcl_first_chunk(pcl); + if (chunk->ch_position > call_len) + return -EINVAL; length = chunk->ch_position; ret = svc_rdma_read_chunk_range(rqstp, head, call_chunk, start, length); @@ -1008,6 +1024,10 @@ static int svc_rdma_read_call_chunk(struct svc_rqst *rqstp, break; start += length; + if (next->ch_position > call_len) + return -EINVAL; + if (head->rc_readbytes > next->ch_position) + return -EINVAL; length = next->ch_position - head->rc_readbytes; ret = svc_rdma_read_chunk_range(rqstp, head, call_chunk, start, length); @@ -1016,7 +1036,9 @@ static int svc_rdma_read_call_chunk(struct svc_rqst *rqstp, } start += length; - length = call_chunk->ch_length - start; + if (start > call_len) + return -EINVAL; + length = call_len - start; return svc_rdma_read_chunk_range(rqstp, head, call_chunk, start, length); } -- 2.53.0