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From: Todd Poynor <toddpoynor@gmail.com>
To: Rob Springer <rspringer@google.com>,
	John Joseph <jnjoseph@google.com>,
	Ben Chan <benchan@chromium.org>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Zhongze Hu <frankhu@chromium.org>, Simon Que <sque@chromium.org>,
	Dmitry Torokhov <dtor@chromium.org>,
	Guenter Roeck <groeck@chromium.org>,
	devel@driverdev.osuosl.org, linux-kernel@vger.kernel.org,
	Todd Poynor <toddpoynor@google.com>
Subject: [PATCH 17/32] staging: gasket: annotate ioctl arg with __user
Date: Tue, 17 Jul 2018 13:56:57 -0700	[thread overview]
Message-ID: <20180717205712.29495-18-toddpoynor@gmail.com> (raw)
In-Reply-To: <20180717205712.29495-1-toddpoynor@gmail.com>

From: Todd Poynor <toddpoynor@google.com>

For sparse checking.

Reported-by: Dmitry Torokhov <dtor@chromium.org>
Signed-off-by: Zhongze Hu <frankhu@chromium.org>
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Reviewed-by: Dmitry Torokhov <dtor@chromium.org>
---
 drivers/staging/gasket/apex_driver.c  | 11 ++--
 drivers/staging/gasket/gasket_core.c  |  6 ++-
 drivers/staging/gasket/gasket_core.h  |  4 +-
 drivers/staging/gasket/gasket_ioctl.c | 72 ++++++++++++++-------------
 drivers/staging/gasket/gasket_ioctl.h |  4 +-
 5 files changed, 52 insertions(+), 45 deletions(-)

diff --git a/drivers/staging/gasket/apex_driver.c b/drivers/staging/gasket/apex_driver.c
index 612b3ab803196..c91c5aff5ab9c 100644
--- a/drivers/staging/gasket/apex_driver.c
+++ b/drivers/staging/gasket/apex_driver.c
@@ -5,6 +5,7 @@
  * Copyright (C) 2018 Google, Inc.
  */
 
+#include <linux/compiler.h>
 #include <linux/delay.h>
 #include <linux/fs.h>
 #include <linux/init.h>
@@ -142,9 +143,9 @@ static int apex_get_status(struct gasket_dev *gasket_dev);
 
 static uint apex_ioctl_check_permissions(struct file *file, uint cmd);
 
-static long apex_ioctl(struct file *file, uint cmd, ulong arg);
+static long apex_ioctl(struct file *file, uint cmd, void __user *arg);
 
-static long apex_clock_gating(struct gasket_dev *gasket_dev, ulong arg);
+static long apex_clock_gating(struct gasket_dev *gasket_dev, void __user *arg);
 
 static int apex_enter_reset(struct gasket_dev *gasket_dev, uint type);
 
@@ -635,7 +636,7 @@ static uint apex_ioctl_check_permissions(struct file *filp, uint cmd)
 /*
  * Apex-specific ioctl handler.
  */
-static long apex_ioctl(struct file *filp, uint cmd, ulong arg)
+static long apex_ioctl(struct file *filp, uint cmd, void __user *arg)
 {
 	struct gasket_dev *gasket_dev = filp->private_data;
 
@@ -655,7 +656,7 @@ static long apex_ioctl(struct file *filp, uint cmd, ulong arg)
  * @gasket_dev: Gasket device pointer.
  * @arg: User ioctl arg, in this case to a apex_gate_clock_ioctl struct.
  */
-static long apex_clock_gating(struct gasket_dev *gasket_dev, ulong arg)
+static long apex_clock_gating(struct gasket_dev *gasket_dev, void __user *arg)
 {
 	struct apex_gate_clock_ioctl ibuf;
 
@@ -663,7 +664,7 @@ static long apex_clock_gating(struct gasket_dev *gasket_dev, ulong arg)
 		return 0;
 
 	if (allow_sw_clock_gating) {
-		if (copy_from_user(&ibuf, (void __user *)arg, sizeof(ibuf)))
+		if (copy_from_user(&ibuf, arg, sizeof(ibuf)))
 			return -EFAULT;
 
 		gasket_log_error(
diff --git a/drivers/staging/gasket/gasket_core.c b/drivers/staging/gasket/gasket_core.c
index 947b4fcc76970..ff34af42bbe7c 100644
--- a/drivers/staging/gasket/gasket_core.c
+++ b/drivers/staging/gasket/gasket_core.c
@@ -14,6 +14,7 @@
 #include "gasket_page_table.h"
 #include "gasket_sysfs.h"
 
+#include <linux/compiler.h>
 #include <linux/delay.h>
 #include <linux/fs.h>
 #include <linux/init.h>
@@ -1823,14 +1824,15 @@ static long gasket_ioctl(struct file *filp, uint cmd, ulong arg)
 		 * check_and_invoke_callback.
 		 */
 		if (driver_desc->ioctl_handler_cb)
-			return driver_desc->ioctl_handler_cb(filp, cmd, arg);
+			return driver_desc->ioctl_handler_cb(
+			    filp, cmd, (void __user *)arg);
 
 		gasket_log_error(
 			gasket_dev, "Received unknown ioctl 0x%x", cmd);
 		return -EINVAL;
 	}
 
-	return gasket_handle_ioctl(filp, cmd, arg);
+	return gasket_handle_ioctl(filp, cmd, (void __user *)arg);
 }
 
 int gasket_reset(struct gasket_dev *gasket_dev, uint reset_type)
diff --git a/drivers/staging/gasket/gasket_core.h b/drivers/staging/gasket/gasket_core.h
index 50ad0c8853183..68b4d2ac9fd6c 100644
--- a/drivers/staging/gasket/gasket_core.h
+++ b/drivers/staging/gasket/gasket_core.h
@@ -315,7 +315,7 @@ struct gasket_dev {
 
 /* Type of the ioctl permissions check callback. See below. */
 typedef int (*gasket_ioctl_permissions_cb_t)(
-	struct file *filp, uint cmd, ulong arg);
+	struct file *filp, uint cmd, void __user *arg);
 
 /*
  * Device type descriptor.
@@ -549,7 +549,7 @@ struct gasket_driver_desc {
 	 * return -EINVAL. Should return an error status (either -EINVAL or
 	 * the error result of the ioctl being handled).
 	 */
-	long (*ioctl_handler_cb)(struct file *filp, uint cmd, ulong arg);
+	long (*ioctl_handler_cb)(struct file *filp, uint cmd, void __user *arg);
 
 	/*
 	 * device_status_cb: Callback to determine device health.
diff --git a/drivers/staging/gasket/gasket_ioctl.c b/drivers/staging/gasket/gasket_ioctl.c
index d0fa05b8bf1d3..ab2376c32c00b 100644
--- a/drivers/staging/gasket/gasket_ioctl.c
+++ b/drivers/staging/gasket/gasket_ioctl.c
@@ -7,6 +7,7 @@
 #include "gasket_interrupt.h"
 #include "gasket_logging.h"
 #include "gasket_page_table.h"
+#include <linux/compiler.h>
 #include <linux/fs.h>
 #include <linux/uaccess.h>
 
@@ -23,17 +24,18 @@
 #endif
 
 static uint gasket_ioctl_check_permissions(struct file *filp, uint cmd);
-static int gasket_set_event_fd(struct gasket_dev *dev, ulong arg);
+static int gasket_set_event_fd(struct gasket_dev *dev, void __user *arg);
 static int gasket_read_page_table_size(
-	struct gasket_dev *gasket_dev, ulong arg);
+	struct gasket_dev *gasket_dev, void __user *arg);
 static int gasket_read_simple_page_table_size(
-	struct gasket_dev *gasket_dev, ulong arg);
+	struct gasket_dev *gasket_dev, void __user *arg);
 static int gasket_partition_page_table(
-	struct gasket_dev *gasket_dev, ulong arg);
-static int gasket_map_buffers(struct gasket_dev *gasket_dev, ulong arg);
-static int gasket_unmap_buffers(struct gasket_dev *gasket_dev, ulong arg);
+	struct gasket_dev *gasket_dev, void __user *arg);
+static int gasket_map_buffers(struct gasket_dev *gasket_dev, void __user *arg);
+static int gasket_unmap_buffers(struct gasket_dev *gasket_dev,
+				void __user *arg);
 static int gasket_config_coherent_allocator(
-	struct gasket_dev *gasket_dev, ulong arg);
+	struct gasket_dev *gasket_dev, void __user *arg);
 
 /*
  * standard ioctl dispatch function.
@@ -43,9 +45,10 @@ static int gasket_config_coherent_allocator(
  *
  * Standard ioctl dispatcher; forwards operations to individual handlers.
  */
-long gasket_handle_ioctl(struct file *filp, uint cmd, ulong arg)
+long gasket_handle_ioctl(struct file *filp, uint cmd, void __user *arg)
 {
 	struct gasket_dev *gasket_dev;
+	ulong intarg = (ulong)arg;
 	int retval;
 
 	gasket_dev = (struct gasket_dev *)filp->private_data;
@@ -74,16 +77,16 @@ long gasket_handle_ioctl(struct file *filp, uint cmd, ulong arg)
 	 */
 	switch (cmd) {
 	case GASKET_IOCTL_RESET:
-		trace_gasket_ioctl_integer_data(arg);
-		retval = gasket_reset(gasket_dev, arg);
+		trace_gasket_ioctl_integer_data(intarg);
+		retval = gasket_reset(gasket_dev, intarg);
 		break;
 	case GASKET_IOCTL_SET_EVENTFD:
 		retval = gasket_set_event_fd(gasket_dev, arg);
 		break;
 	case GASKET_IOCTL_CLEAR_EVENTFD:
-		trace_gasket_ioctl_integer_data(arg);
+		trace_gasket_ioctl_integer_data(intarg);
 		retval = gasket_interrupt_clear_eventfd(
-			gasket_dev->interrupt_data, (int)arg);
+			gasket_dev->interrupt_data, (int)intarg);
 		break;
 	case GASKET_IOCTL_PARTITION_PAGE_TABLE:
 		trace_gasket_ioctl_integer_data(arg);
@@ -91,7 +94,7 @@ long gasket_handle_ioctl(struct file *filp, uint cmd, ulong arg)
 		break;
 	case GASKET_IOCTL_NUMBER_PAGE_TABLES:
 		trace_gasket_ioctl_integer_data(gasket_dev->num_page_tables);
-		if (copy_to_user((void __user *)arg,
+		if (copy_to_user(arg,
 				 &gasket_dev->num_page_tables,
 				 sizeof(uint64_t)))
 			retval = -EFAULT;
@@ -217,11 +220,11 @@ static uint gasket_ioctl_check_permissions(struct file *filp, uint cmd)
  * @gasket_dev: Pointer to the current gasket_dev we're using.
  * @arg: Pointer to gasket_interrupt_eventfd struct in userspace.
  */
-static int gasket_set_event_fd(struct gasket_dev *gasket_dev, ulong arg)
+static int gasket_set_event_fd(struct gasket_dev *gasket_dev, void __user *arg)
 {
 	struct gasket_interrupt_eventfd die;
 
-	if (copy_from_user(&die, (void __user *)arg,
+	if (copy_from_user(&die, arg,
 			   sizeof(struct gasket_interrupt_eventfd))) {
 		return -EFAULT;
 	}
@@ -237,13 +240,13 @@ static int gasket_set_event_fd(struct gasket_dev *gasket_dev, ulong arg)
  * @gasket_dev: Pointer to the current gasket_dev we're using.
  * @arg: Pointer to gasket_page_table_ioctl struct in userspace.
  */
-static int gasket_read_page_table_size(struct gasket_dev *gasket_dev, ulong arg)
+static int gasket_read_page_table_size(struct gasket_dev *gasket_dev,
+				       void __user *arg)
 {
 	int ret = 0;
 	struct gasket_page_table_ioctl ibuf;
 
-	if (copy_from_user(&ibuf, (void __user *)arg,
-			   sizeof(struct gasket_page_table_ioctl)))
+	if (copy_from_user(&ibuf, arg, sizeof(struct gasket_page_table_ioctl)))
 		return -EFAULT;
 
 	if (ibuf.page_table_index >= gasket_dev->num_page_tables)
@@ -256,7 +259,7 @@ static int gasket_read_page_table_size(struct gasket_dev *gasket_dev, ulong arg)
 		ibuf.page_table_index, ibuf.size, ibuf.host_address,
 		ibuf.device_address);
 
-	if (copy_to_user((void __user *)arg, &ibuf, sizeof(ibuf)))
+	if (copy_to_user(arg, &ibuf, sizeof(ibuf)))
 		return -EFAULT;
 
 	return ret;
@@ -268,13 +271,12 @@ static int gasket_read_page_table_size(struct gasket_dev *gasket_dev, ulong arg)
  * @arg: Pointer to gasket_page_table_ioctl struct in userspace.
  */
 static int gasket_read_simple_page_table_size(
-	struct gasket_dev *gasket_dev, ulong arg)
+	struct gasket_dev *gasket_dev, void __user *arg)
 {
 	int ret = 0;
 	struct gasket_page_table_ioctl ibuf;
 
-	if (copy_from_user(&ibuf, (void __user *)arg,
-			   sizeof(struct gasket_page_table_ioctl)))
+	if (copy_from_user(&ibuf, arg, sizeof(struct gasket_page_table_ioctl)))
 		return -EFAULT;
 
 	if (ibuf.page_table_index >= gasket_dev->num_page_tables)
@@ -287,7 +289,7 @@ static int gasket_read_simple_page_table_size(
 		ibuf.page_table_index, ibuf.size, ibuf.host_address,
 		ibuf.device_address);
 
-	if (copy_to_user((void __user *)arg, &ibuf, sizeof(ibuf)))
+	if (copy_to_user(arg, &ibuf, sizeof(ibuf)))
 		return -EFAULT;
 
 	return ret;
@@ -298,14 +300,14 @@ static int gasket_read_simple_page_table_size(
  * @gasket_dev: Pointer to the current gasket_dev we're using.
  * @arg: Pointer to gasket_page_table_ioctl struct in userspace.
  */
-static int gasket_partition_page_table(struct gasket_dev *gasket_dev, ulong arg)
+static int gasket_partition_page_table(struct gasket_dev *gasket_dev,
+				       void __user *arg)
 {
 	int ret;
 	struct gasket_page_table_ioctl ibuf;
 	uint max_page_table_size;
 
-	if (copy_from_user(&ibuf, (void __user *)arg,
-			   sizeof(struct gasket_page_table_ioctl)))
+	if (copy_from_user(&ibuf, arg, sizeof(struct gasket_page_table_ioctl)))
 		return -EFAULT;
 
 	trace_gasket_ioctl_page_table_data(
@@ -339,12 +341,12 @@ static int gasket_partition_page_table(struct gasket_dev *gasket_dev, ulong arg)
  * @gasket_dev: Pointer to the current gasket_dev we're using.
  * @arg: Pointer to a gasket_page_table_ioctl struct in userspace.
  */
-static int gasket_map_buffers(struct gasket_dev *gasket_dev, ulong arg)
+static int gasket_map_buffers(struct gasket_dev *gasket_dev,
+			      void __user *arg)
 {
 	struct gasket_page_table_ioctl ibuf;
 
-	if (copy_from_user(&ibuf, (void __user *)arg,
-			   sizeof(struct gasket_page_table_ioctl)))
+	if (copy_from_user(&ibuf, arg, sizeof(struct gasket_page_table_ioctl)))
 		return -EFAULT;
 
 	trace_gasket_ioctl_page_table_data(
@@ -369,12 +371,12 @@ static int gasket_map_buffers(struct gasket_dev *gasket_dev, ulong arg)
  * @gasket_dev: Pointer to the current gasket_dev we're using.
  * @arg: Pointer to a gasket_page_table_ioctl struct in userspace.
  */
-static int gasket_unmap_buffers(struct gasket_dev *gasket_dev, ulong arg)
+static int gasket_unmap_buffers(struct gasket_dev *gasket_dev,
+				void __user *arg)
 {
 	struct gasket_page_table_ioctl ibuf;
 
-	if (copy_from_user(&ibuf, (void __user *)arg,
-			   sizeof(struct gasket_page_table_ioctl)))
+	if (copy_from_user(&ibuf, arg, sizeof(struct gasket_page_table_ioctl)))
 		return -EFAULT;
 
 	trace_gasket_ioctl_page_table_data(
@@ -402,12 +404,12 @@ static int gasket_unmap_buffers(struct gasket_dev *gasket_dev, ulong arg)
  * @arg: Pointer to a gasket_coherent_alloc_config_ioctl struct in userspace.
  */
 static int gasket_config_coherent_allocator(
-	struct gasket_dev *gasket_dev, ulong arg)
+	struct gasket_dev *gasket_dev, void __user *arg)
 {
 	int ret;
 	struct gasket_coherent_alloc_config_ioctl ibuf;
 
-	if (copy_from_user(&ibuf, (void __user *)arg,
+	if (copy_from_user(&ibuf, arg,
 			   sizeof(struct gasket_coherent_alloc_config_ioctl)))
 		return -EFAULT;
 
@@ -431,7 +433,7 @@ static int gasket_config_coherent_allocator(
 			gasket_dev, ibuf.size, &ibuf.dma_address,
 			ibuf.page_table_index);
 	}
-	if (copy_to_user((void __user *)arg, &ibuf, sizeof(ibuf)))
+	if (copy_to_user(arg, &ibuf, sizeof(ibuf)))
 		return -EFAULT;
 
 	return ret;
diff --git a/drivers/staging/gasket/gasket_ioctl.h b/drivers/staging/gasket/gasket_ioctl.h
index 461fab27a3e52..2c6bd3e6ba2c9 100644
--- a/drivers/staging/gasket/gasket_ioctl.h
+++ b/drivers/staging/gasket/gasket_ioctl.h
@@ -5,6 +5,8 @@
 
 #include "gasket_core.h"
 
+#include <linux/compiler.h>
+
 /*
  * Handle Gasket common ioctls.
  * @filp: Pointer to the ioctl's file.
@@ -13,7 +15,7 @@
  *
  * Returns 0 on success and nonzero on failure.
  */
-long gasket_handle_ioctl(struct file *filp, uint cmd, ulong arg);
+long gasket_handle_ioctl(struct file *filp, uint cmd, void __user *arg);
 
 /*
  * Determines if an ioctl is part of the standard Gasket framework.
-- 
2.18.0.203.gfac676dfb9-goog


  parent reply	other threads:[~2018-07-17 21:05 UTC|newest]

Thread overview: 42+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-07-17 20:56 [PATCH 00/32 v3] staging: gasket: sundry fixes and fixups Todd Poynor
2018-07-17 20:56 ` [PATCH 01/32] staging: gasket: remove X86 Kconfig restriction Todd Poynor
2018-07-17 20:56 ` [PATCH 02/32] staging: gasket: fix typo in apex_enter_reset Todd Poynor
2018-07-17 20:56 ` [PATCH 03/32] staging: gasket: fix typo in gasket_core.h comments Todd Poynor
2018-07-17 20:56 ` [PATCH 04/32] staging: gasket: whitespace fix in gasket_page_table_init Todd Poynor
2018-07-17 20:56 ` [PATCH 05/32] staging: gasket: remove driver registration on class creation failure Todd Poynor
2018-07-17 20:56 ` [PATCH 06/32] staging: gasket: hold mutex on gasket driver unregistration Todd Poynor
2018-07-17 20:56 ` [PATCH 07/32] staging: gasket: Return EBUSY on mapping create when already in use Todd Poynor
2018-07-17 20:56 ` [PATCH 08/32] staging: gasket: Remove stale pointers on error allocating attr array Todd Poynor
2018-07-17 20:56 ` [PATCH 09/32] staging: gasket: convert gasket_mmap_has_permissions to bool return Todd Poynor
2018-07-17 20:56 ` [PATCH 10/32] staging: gasket: fix gasket_wait_with_reschedule timeout return code Todd Poynor
2018-07-17 20:56 ` [PATCH 11/32] staging: gasket: gasket_wait_with_reschedule use msleep Todd Poynor
2018-07-17 20:56 ` [PATCH 12/32] staging: gasket: gasket_wait_with_reschedule simplify logic Todd Poynor
2018-07-17 20:56 ` [PATCH 13/32] staging: gasket: gasket_wait_with_reschedule use 32 bits of retry count Todd Poynor
2018-07-17 20:56 ` [PATCH 14/32] staging: gasket: bail out of reset sequence on device callback error Todd Poynor
2018-07-17 20:56 ` [PATCH 15/32] staging: gasket: drop gasket_cdev_get_info, use container_of Todd Poynor
2018-07-17 20:56 ` [PATCH 16/32] staging: gasket: always allow root open for write Todd Poynor
2018-07-19  9:29   ` Greg Kroah-Hartman
2018-07-19 23:47     ` Todd Poynor
2018-07-17 20:56 ` Todd Poynor [this message]
2018-07-19  9:37   ` [PATCH 17/32] staging: gasket: annotate ioctl arg with __user Greg Kroah-Hartman
2018-07-20  2:44     ` Todd Poynor
2018-07-20  5:43       ` Greg Kroah-Hartman
2018-07-30  7:00       ` Dan Carpenter
2018-07-17 20:56 ` [PATCH 18/32] staging: gasket: gasket_enable_dev remove unnecessary variable Todd Poynor
2018-07-17 20:56 ` [PATCH 19/32] staging: gasket: remove code for no physical device Todd Poynor
2018-07-17 20:57 ` [PATCH 20/32] staging: gasket: fix class create bug handling Todd Poynor
2018-07-17 20:57 ` [PATCH 21/32] staging: gasket: remove unnecessary code in coherent allocator Todd Poynor
2018-07-17 20:57 ` [PATCH 22/32] staging: gasket: don't treat no device reset callback as an error Todd Poynor
2018-07-17 20:57 ` [PATCH 23/32] staging: gasket: gasket_mmap return error instead of valid BAR index Todd Poynor
2018-07-17 20:57 ` [PATCH 24/32] staging: gasket: apex_clock_gating simplify logic, reduce indentation Todd Poynor
2018-07-17 20:57 ` [PATCH 25/32] staging: gasket: apex_ioctl_check_permissions use bool return type Todd Poynor
2018-07-17 20:57 ` [PATCH 26/32] staging: gasket: gasket page table functions " Todd Poynor
2018-07-17 20:57 ` [PATCH 27/32] staging: gasket: remove else clause after return in if clause Todd Poynor
2018-07-17 20:57 ` [PATCH 28/32] staging: gasket: fix comment syntax in apex.h Todd Poynor
2018-07-17 20:57 ` [PATCH 29/32] staging: gasket: remove unnecessary parens in page table code Todd Poynor
2018-07-17 20:57 ` [PATCH 30/32] staging: gasket: gasket_mmap use PAGE_MASK Todd Poynor
2018-07-17 20:57 ` [PATCH 31/32] staging: gasket: remove extra parens in gasket_write_mappable_regions Todd Poynor
2018-07-17 20:57 ` [PATCH 32/32] staging: gasket: fix multi-line comment syntax in gasket_core.h Todd Poynor
  -- strict thread matches above, loose matches on Subject: below --
2018-07-17  2:08 [PATCH 00/32 v2] staging: gasket: sundry fixes and fixups Todd Poynor
2018-07-17  2:09 ` [PATCH 17/32] staging: gasket: annotate ioctl arg with __user Todd Poynor
2018-07-17 10:26   ` Dan Carpenter
2018-07-17 18:20     ` Todd Poynor

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