From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 BD5FD3D47D0; Mon, 4 May 2026 13:54:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777902865; cv=none; b=c+MPutNiLP8O3qpKZMC9uJMVqJKZj5a2oZMJJflPVH6XZcdwEdQMW8dpHORc6gHV5bJsbKphImtDDPYdxgXT8GRcECfepWnaDZMKjaoja/Vq+mI3sKq6fW2qVP3vV9T9w9oNvsWoQY7XLbxTCuEnLNn8PSQlOMzUCPsFIAqCqdw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777902865; c=relaxed/simple; bh=0BjoDPx8GFbPw7yEBjHCgefNqnPpL/LOQiEsWFioBEo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=QSIr0j5T01Ahw4Zd3snPMY1trScalo2POv6vwKWvBw0EyJX8xtKSJXtvNzer7LeJUsddm146RYqOzURB3iV85e7nYVD052pwoq08BgMzRm9gAVhcKcvUg8CJzZIZtIXeLF+d17L1rHj9Ezyddr3FnOfn//U4dJCZ6Dq1VyvmZJY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=1K8t4OkU; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="1K8t4OkU" Received: by smtp.kernel.org (Postfix) with ESMTPSA id EE13FC2BCB8; Mon, 4 May 2026 13:54:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1777902865; bh=0BjoDPx8GFbPw7yEBjHCgefNqnPpL/LOQiEsWFioBEo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=1K8t4OkUj7jW7mynnS+FQBX1XhpngH8nMkhYD0A/4Cvkd+KBrNjxVdIwGY+PY4rm5 0Evks5YCVc8ZQN/FBa+LYlQC5iShoMrjYzFahZ1mnUYrR6W+ZDN2EszpSmIz2rr9mw N88i5yjYxCt9BD31icMG9xim7V1ebULJTs0WkbpY= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Yuhao Jiang , ychen@northwestern.edu, Tyllis Xu Subject: [PATCH 7.0 013/307] misc: ibmasm: fix OOB MMIO read in ibmasm_handle_mouse_interrupt() Date: Mon, 4 May 2026 15:48:18 +0200 Message-ID: <20260504135143.325708297@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260504135142.814938198@linuxfoundation.org> References: <20260504135142.814938198@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 7.0-stable review patch. If anyone has any objections, please let me know. ------------------ From: Tyllis Xu commit 4b6e6ead556734bdc14024c5f837132b1e7a4b84 upstream. ibmasm_handle_mouse_interrupt() performs an out-of-bounds MMIO read when the queue reader or writer index from hardware exceeds REMOTE_QUEUE_SIZE (60). A compromised service processor can trigger this by writing an out-of-range value to the reader or writer MMIO register before asserting an interrupt. Since writer is re-read from hardware on every loop iteration, it can also be set to an out-of-range value after the loop has already started. The root cause is that get_queue_reader() and get_queue_writer() return raw readl() values that are passed directly into get_queue_entry(), which computes: queue_begin + reader * sizeof(struct remote_input) with no bounds check. This unchecked MMIO address is then passed to memcpy_fromio(), reading 8 bytes from unintended device registers. For sufficiently large values the address falls outside the PCI BAR mapping entirely, triggering a machine check exception. Fix by checking both indices against REMOTE_QUEUE_SIZE at the top of the loop body, before any call to get_queue_entry(). On an out-of-range value, reset the reader register to 0 via set_queue_reader() before breaking, so that normal queue operation can resume if the corrupted hardware state is transient. Reported-by: Yuhao Jiang Fixes: 278d72ae8803 ("[PATCH] ibmasm driver: redesign handling of remote control events") Cc: stable@vger.kernel.org Cc: ychen@northwestern.edu Signed-off-by: Tyllis Xu Link: https://patch.msgid.link/20260308062108.258940-1-LivelyCarpet87@gmail.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Greg Kroah-Hartman --- drivers/misc/ibmasm/remote.c | 5 +++++ 1 file changed, 5 insertions(+) --- a/drivers/misc/ibmasm/remote.c +++ b/drivers/misc/ibmasm/remote.c @@ -177,6 +177,11 @@ void ibmasm_handle_mouse_interrupt(struc writer = get_queue_writer(sp); while (reader != writer) { + if (reader >= REMOTE_QUEUE_SIZE || writer >= REMOTE_QUEUE_SIZE) { + set_queue_reader(sp, 0); + break; + } + memcpy_fromio(&input, get_queue_entry(sp, reader), sizeof(struct remote_input));