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 2458D5349A0; Thu, 17 Sep 2026 17:01:44 +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=1789664506; cv=none; b=UWdD0Wj3DWTlaxGpGZPYjYW+/29U53d4TmCUa2qCn1LuzftT30F401bwA0hdKK+LyNhKsx32RBuSndCLdaZQBOjruo+5p08pQv0rwlw0/a1Icxd55wC7FqcPVhcWFjddcaCp0M/aKAS0YVYVzma8e2yHWjCBG9DWe609nKxEhMw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789664506; c=relaxed/simple; bh=phg92k3AamO0q3CLGrGUN68MA57CW6wuu9PuAFl+j/U=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=paMC4u7STB0OkAAo60opu6oSQy1YAhPQ+NuRMV3+0DJkd4sZXvUxFYzODXbSphRfx5OO5n7gS1brDlVb9o+6aKSfyMZEsxUQFRNTqC5kcKYaY6UY0EfCsRzmiJIjZ27/0eFO7jsbz0lCl+mm97zf/dw497NepSC7GsLbFIVbGg0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=wVy5EBNT; 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="wVy5EBNT" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2F05C1F00899; Thu, 17 Sep 2026 17:01:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789664504; bh=IUVkgFYSbKcxvuWMAf19fPS/J6UrTmGxQLo4ELsydUU=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=wVy5EBNToCJ6ptqrQcVENuMEOy2bZ+/pODDUcXTuERh11ORN8qU0C3V/oFoo1tYCz hiouRSe5FtuWT6L9FrPQ7oGh+F7LH8FfL+7CeKr7BIJv9dHSnb4/5kG0eb7zTQFuHp mHsSJ8HaNiHnXJ7j3kP3PlqiinZah2ZDsI4CI17c= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Aurelien DESBRIERES , Md Haris Iqbal , Jason Gunthorpe , Sasha Levin Subject: [PATCH 6.18 0353/1250] RDMA/rtrs-srv: Fix integer underflow in process_read and process_write Date: Thu, 17 Sep 2026 16:02:28 +0100 Message-ID: <20260917151601.635781797@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260917151551.901433442@linuxfoundation.org> References: <20260917151551.901433442@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 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Aurelien DESBRIERES [ Upstream commit 54bf38b27afc08a0eb6b732f9c14eb8a4bcb66b5 ] usr_len is read from a network-supplied message field (le16_to_cpu) and used to compute data_len = off - usr_len without validating that usr_len <= off. A malicious RDMA client can send usr_len > off causing an integer underflow, resulting in data_len wrapping to a huge size_t value which is then passed to the rdma_ev callback as a memory length, leading to out-of-bounds memory access. Fix by reading and validating usr_len <= off before rtrs_srv_get_ops_ids() in both process_read() and process_write(), ensuring the early return path acquires no reference and has no resource leak. Link: https://patch.msgid.link/r/20260608134802.5019-1-aurelien@hackers.camp Reported-by: Aurelien DESBRIERES Reviewed-by: Md Haris Iqbal Signed-off-by: Aurelien DESBRIERES Assisted-by: Claude Acked-by: Md Haris Iqbal Signed-off-by: Jason Gunthorpe Signed-off-by: Sasha Levin --- drivers/infiniband/ulp/rtrs/rtrs-srv.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/drivers/infiniband/ulp/rtrs/rtrs-srv.c b/drivers/infiniband/ulp/rtrs/rtrs-srv.c index 1fc67fdff9fc2..12a9a888fe0ee 100644 --- a/drivers/infiniband/ulp/rtrs/rtrs-srv.c +++ b/drivers/infiniband/ulp/rtrs/rtrs-srv.c @@ -1049,6 +1049,11 @@ static void process_read(struct rtrs_srv_con *con, "Processing read request failed, invalid message\n"); return; } + usr_len = le16_to_cpu(msg->usr_len); + if (usr_len > off) { + pr_debug("rtrs-srv: Invalid usr_len %zu > off %u\n", usr_len, off); + return; + } rtrs_srv_get_ops_ids(srv_path); rtrs_srv_update_rdma_stats(srv_path->stats, off, READ); id = srv_path->ops_ids[buf_id]; @@ -1056,7 +1061,6 @@ static void process_read(struct rtrs_srv_con *con, id->dir = READ; id->msg_id = buf_id; id->rd_msg = msg; - usr_len = le16_to_cpu(msg->usr_len); data_len = off - usr_len; data = page_address(srv->chunks[buf_id]); ret = ctx->ops.rdma_ev(srv->priv, id, data, data_len, @@ -1102,6 +1106,11 @@ static void process_write(struct rtrs_srv_con *con, rtrs_srv_state_str(srv_path->state)); return; } + usr_len = le16_to_cpu(req->usr_len); + if (usr_len > off) { + pr_debug("rtrs-srv: Invalid usr_len %zu > off %u\n", usr_len, off); + return; + } rtrs_srv_get_ops_ids(srv_path); rtrs_srv_update_rdma_stats(srv_path->stats, off, WRITE); id = srv_path->ops_ids[buf_id]; @@ -1109,7 +1118,6 @@ static void process_write(struct rtrs_srv_con *con, id->dir = WRITE; id->msg_id = buf_id; - usr_len = le16_to_cpu(req->usr_len); data_len = off - usr_len; data = page_address(srv->chunks[buf_id]); ret = ctx->ops.rdma_ev(srv->priv, id, data, data_len, -- 2.53.0