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 D99F937F306; Fri, 4 Sep 2026 06:14:39 +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=1788502481; cv=none; b=k/A5Poem5smq3rhpnWp5ZCnnjmV5AiYl8lv9tQ+VZ8AhoTI2l/GyvSXUJkfQloOPduWDOZeZc1HN22EDkBhWKmfRqt+zD1TrJk/I93T7MnKMdm1OSSe0CklXHhXvoVs+a43B82FhtcT2FmWgM7Em8R+5S7Z4KuktYtEMHa3X79w= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788502481; c=relaxed/simple; bh=7odl+uunKpbiHJo/Cy4Rrnirq4RIW4/XCpeMNtqb0OQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ABIStClfwvWi/9rNbb/Us8GRmKj39WmcCu0HrQjg44IL2t5IfrgAXMUSX+yF6VX3RbgGfFTXHzGn1OfrPSnzQP7hr5mqVIyENNCb/CEnq63Z3XKbgwF3l3RnNMzAG0x6q0fh0y7sWGKNJYCCxpcIrRsuL3I0SkHLaOyZNlm9aKc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=ljMgldI+; 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="ljMgldI+" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3EE201F00A3D; Fri, 4 Sep 2026 06:14:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1788502479; bh=C1foSaZImcAVfC6frIekjhRzCZUg94zOssTp1ieNOxo=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=ljMgldI+sOuKCsTMOV1s4RthcIEPyDS690ArdopMBn2623WNRcg7zpz8M7JY16GCN tfKGOxIRc2KXTLlWafNYbSFWMit57cvJe4Ee2jzhZemC8NgyPu6rr+ZQBjQXKoaprd 2C72baiOZ5kcLR2M5qDrfh3ENMvghT7Rtj5f+jGs= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Jeff Layton , Chuck Lever Subject: [PATCH 6.12 220/403] svcrdma: Validate Read chunk positions before reconstruction Date: Fri, 4 Sep 2026 07:00:23 +0200 Message-ID: <20260904045739.868597046@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260904045734.806166532@linuxfoundation.org> References: <20260904045734.806166532@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: Chuck Lever commit 3779b7b9e7d1c8ba4738f9d327de3b0288cefe9b upstream. 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: Greg Kroah-Hartman --- net/sunrpc/xprtrdma/svc_rdma_rw.c | 38 ++++++++++++++++++++++++++++++-------- 1 file changed, 30 insertions(+), 8 deletions(-) --- a/net/sunrpc/xprtrdma/svc_rdma_rw.c +++ b/net/sunrpc/xprtrdma/svc_rdma_rw.c @@ -817,7 +817,7 @@ static int svc_rdma_build_read_chunk(str * 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 @@ -834,9 +834,13 @@ static int svc_rdma_copy_inline_range(st 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; @@ -887,9 +891,10 @@ svc_rdma_read_multiple_chunks(struct svc { 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; @@ -907,6 +912,8 @@ svc_rdma_read_multiple_chunks(struct svc 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) @@ -914,7 +921,9 @@ svc_rdma_read_multiple_chunks(struct svc } 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); } @@ -939,8 +948,12 @@ svc_rdma_read_multiple_chunks(struct svc 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); } /** @@ -1014,14 +1027,17 @@ static int svc_rdma_read_call_chunk(stru 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); @@ -1038,6 +1054,10 @@ static int svc_rdma_read_call_chunk(stru 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); @@ -1046,7 +1066,9 @@ static int svc_rdma_read_call_chunk(stru } 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); }