From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 781AFC6379F for ; Wed, 22 Feb 2023 12:12:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229560AbjBVMM1 (ORCPT ); Wed, 22 Feb 2023 07:12:27 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60402 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229884AbjBVMM0 (ORCPT ); Wed, 22 Feb 2023 07:12:26 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4543F13D73 for ; Wed, 22 Feb 2023 04:12:25 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id C73386140F for ; Wed, 22 Feb 2023 12:12:24 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B8C48C4339C; Wed, 22 Feb 2023 12:12:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1677067944; bh=NAZzcRGXuCZ4Wgvxo5bUG3exRopxVrOolRQRbAvFNIM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=p98R/FsqFU5sRIbbRzc4bv7DkCh/hFwFaxPyFMJFcvlhJ7shvt2ME+1kD9iqlRoHX dgboHNhPhnpdeVdxdvzfZc0qL245G3kk6pkYT2M0rAjniBCVG+X7Yad9iuMkLrIOOr 2tZGt+qENhUzHNhQKWlWdVv7fxGBAwwpPQGlMiou/5byvAJPFR5dTKkgiwJ/fprmXX VUUe+UM+zjKCLz4swsqW8OvjX5dK3GN2IocpRvaXTiSWExz0PsnQXe4KAKeJOrSquL 65gfQHvlhUA+8gKFjp/D9r13WcAf/sxosdB3m9NekS2RZ9xAIiGCHA+6huQibLg/hP 1PgujMw+BWjDg== From: Lee Jones To: lee@kernel.org Cc: stable@vger.kernel.org, Todd Kjos , Martijn Coenen , Christian Brauner , Greg Kroah-Hartman , Carlos Llamas Subject: [PATCH v5.15.y 1/5] binder: read pre-translated fds from sender buffer Date: Wed, 22 Feb 2023 12:12:04 +0000 Message-Id: <20230222121208.898198-2-lee@kernel.org> X-Mailer: git-send-email 2.39.2.637.g21b0678d19-goog In-Reply-To: <20230222121208.898198-1-lee@kernel.org> References: <20230222121208.898198-1-lee@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Todd Kjos commit 656e01f3ab54afe71bed066996fc2640881e1220 upstream. This patch is to prepare for an up coming patch where we read pre-translated fds from the sender buffer and translate them before copying them to the target. It does not change run time. The patch adds two new parameters to binder_translate_fd_array() to hold the sender buffer and sender buffer parent. These parameters let us call copy_from_user() directly from the sender instead of using binder_alloc_copy_from_buffer() to copy from the target. Also the patch adds some new alignment checks. Previously the alignment checks would have been done in a different place, but this lets us print more useful error messages. Reviewed-by: Martijn Coenen Acked-by: Christian Brauner Signed-off-by: Todd Kjos Link: https://lore.kernel.org/r/20211130185152.437403-4-tkjos@google.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Carlos Llamas Signed-off-by: Lee Jones --- drivers/android/binder.c | 39 ++++++++++++++++++++++++++++++++------- 1 file changed, 32 insertions(+), 7 deletions(-) diff --git a/drivers/android/binder.c b/drivers/android/binder.c index 00c6c03ff8222..67f96d2959280 100644 --- a/drivers/android/binder.c +++ b/drivers/android/binder.c @@ -2270,15 +2270,17 @@ static int binder_translate_fd(u32 fd, binder_size_t fd_offset, } static int binder_translate_fd_array(struct binder_fd_array_object *fda, + const void __user *sender_ubuffer, struct binder_buffer_object *parent, + struct binder_buffer_object *sender_uparent, struct binder_transaction *t, struct binder_thread *thread, struct binder_transaction *in_reply_to) { binder_size_t fdi, fd_buf_size; binder_size_t fda_offset; + const void __user *sender_ufda_base; struct binder_proc *proc = thread->proc; - struct binder_proc *target_proc = t->to_proc; fd_buf_size = sizeof(u32) * fda->num_fds; if (fda->num_fds >= SIZE_MAX / sizeof(u32)) { @@ -2302,7 +2304,10 @@ static int binder_translate_fd_array(struct binder_fd_array_object *fda, */ fda_offset = (parent->buffer - (uintptr_t)t->buffer->user_data) + fda->parent_offset; - if (!IS_ALIGNED((unsigned long)fda_offset, sizeof(u32))) { + sender_ufda_base = (void __user *)sender_uparent->buffer + fda->parent_offset; + + if (!IS_ALIGNED((unsigned long)fda_offset, sizeof(u32)) || + !IS_ALIGNED((unsigned long)sender_ufda_base, sizeof(u32))) { binder_user_error("%d:%d parent offset not aligned correctly.\n", proc->pid, thread->pid); return -EINVAL; @@ -2311,10 +2316,9 @@ static int binder_translate_fd_array(struct binder_fd_array_object *fda, u32 fd; int ret; binder_size_t offset = fda_offset + fdi * sizeof(fd); + binder_size_t sender_uoffset = fdi * sizeof(fd); - ret = binder_alloc_copy_from_buffer(&target_proc->alloc, - &fd, t->buffer, - offset, sizeof(fd)); + ret = copy_from_user(&fd, sender_ufda_base + sender_uoffset, sizeof(fd)); if (!ret) ret = binder_translate_fd(fd, offset, t, thread, in_reply_to); @@ -2987,6 +2991,8 @@ static void binder_transaction(struct binder_proc *proc, case BINDER_TYPE_FDA: { struct binder_object ptr_object; binder_size_t parent_offset; + struct binder_object user_object; + size_t user_parent_size; struct binder_fd_array_object *fda = to_binder_fd_array_object(hdr); size_t num_valid = (buffer_offset - off_start_offset) / @@ -3018,8 +3024,27 @@ static void binder_transaction(struct binder_proc *proc, return_error_line = __LINE__; goto err_bad_parent; } - ret = binder_translate_fd_array(fda, parent, t, thread, - in_reply_to); + /* + * We need to read the user version of the parent + * object to get the original user offset + */ + user_parent_size = + binder_get_object(proc, user_buffer, t->buffer, + parent_offset, &user_object); + if (user_parent_size != sizeof(user_object.bbo)) { + binder_user_error("%d:%d invalid ptr object size: %zd vs %zd\n", + proc->pid, thread->pid, + user_parent_size, + sizeof(user_object.bbo)); + return_error = BR_FAILED_REPLY; + return_error_param = -EINVAL; + return_error_line = __LINE__; + goto err_bad_parent; + } + ret = binder_translate_fd_array(fda, user_buffer, + parent, + &user_object.bbo, t, + thread, in_reply_to); if (!ret) ret = binder_alloc_copy_to_buffer(&target_proc->alloc, t->buffer, -- 2.39.2.637.g21b0678d19-goog