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 B3F944BB5CE for ; Thu, 3 Sep 2026 14:32:18 +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=1788445942; cv=none; b=QnfBXQdCiNJ26J+5d93xjRJn9U/flyK+V4bNiuCKvPu+f/c+wbf8XSZhWYqFAYuLDtL5pdEZQ3tWq1wDdsUBhYeNLnJMKJDBpq57fjDdaLxc9fvZUz1yLCgcRkcCzMYEUSZ9kP8AvsA33hlLrQXiR/eLJt0sePf/b5NzlRQQdP0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788445942; c=relaxed/simple; bh=ob6swEXxJ9WaY4ynk/14SdPBjrqI+bjrjUZBrshrVkI=; h=Subject:To:Cc:From:Date:Message-ID:MIME-Version:Content-Type; b=dH8kt4rHAD3tzmMqvi7rPXaSMkLUmi+Dgg/moI20Zn40OuZq/++FCQU9QHFoBm+W6K89YPzvMbSVK2nBnjkCnIlCbKWdEEH46aEr0V+HPn+UPIpdOAxBEXcOuDsAU3/HwMliDsQ0e3zQYGqdfenwaKM9KzuvBAKYUKyDL80r0AI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=AK5yct7Q; 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="AK5yct7Q" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D21991F00A3A; Thu, 3 Sep 2026 14:32:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1788445937; bh=oYGBbdYqWMBGbEGRLcddXXA6jaHs3FS9z5qeFCE8DF4=; h=Subject:To:Cc:From:Date; b=AK5yct7QwKm9+HFDzq8CdBOPn0FAoaaW/nax9OniuM8N3VLLMhHQn7dtCj3HQB+fL VzDIwiHyqvMhCWuxugCYSvKWHRrURSj0nluwUOq7WOjpiT1XPqzbZr1xR7RvIzHIZ3 QVwrgGYGoKLoVn8GEBSbCbMjIOXytW1ujPU6XxvI= Subject: FAILED: patch "[PATCH] svcrdma: Validate Read chunk positions before reconstruction" failed to apply to 6.1-stable tree To: cel@kernel.org,chuck.lever@oracle.com,jlayton@kernel.org Cc: From: Date: Thu, 03 Sep 2026 16:11:10 +0200 Message-ID: <2026090310-onto-impotence-7944@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 6.1-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-6.1.y git checkout FETCH_HEAD git cherry-pick -x 3779b7b9e7d1c8ba4738f9d327de3b0288cefe9b # git commit -s git send-email --to '' --in-reply-to '2026090310-onto-impotence-7944@gregkh' --subject-prefix 'PATCH 6.1.y' 'HEAD^..' Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 3779b7b9e7d1c8ba4738f9d327de3b0288cefe9b Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Tue, 26 May 2026 09:35:55 -0400 Subject: [PATCH] svcrdma: Validate Read chunk positions before reconstruction 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 diff --git a/net/sunrpc/xprtrdma/svc_rdma_rw.c b/net/sunrpc/xprtrdma/svc_rdma_rw.c index f7fd22cc4a59..8dae418d15b4 100644 --- a/net/sunrpc/xprtrdma/svc_rdma_rw.c +++ b/net/sunrpc/xprtrdma/svc_rdma_rw.c @@ -847,7 +847,7 @@ 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 @@ -864,9 +864,13 @@ 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; @@ -917,9 +921,10 @@ 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; @@ -937,6 +942,8 @@ 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) @@ -944,7 +951,9 @@ 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); } @@ -969,8 +978,12 @@ 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); } /** @@ -1039,14 +1052,17 @@ 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); @@ -1063,6 +1079,10 @@ 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); @@ -1071,7 +1091,9 @@ 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); }