From: Arnd Bergmann <arnd@kernel.org>
To: Jiri Kosina <jikos@kernel.org>, Benjamin Tissoires <bentiss@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>,
Peter Hutterer <peter.hutterer@who-t.net>,
linux-input@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH] HID: tighten ioctl command parsing
Date: Fri, 11 Jul 2025 09:28:43 +0200 [thread overview]
Message-ID: <20250711072847.2836962-1-arnd@kernel.org> (raw)
From: Arnd Bergmann <arnd@arndb.de>
The handling for variable-length ioctl commands in hidraw_ioctl() is
rather complex and the check for the data direction is incomplete.
Simplify this code using a switch() statement with the size masked
out, to ensure the rest of the command is correctly matched.
Fixes: 9188e79ec3fd ("HID: add phys and name ioctls to hidraw")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
drivers/hid/hidraw.c | 123 ++++++++++++++++++-------------------------
1 file changed, 50 insertions(+), 73 deletions(-)
diff --git a/drivers/hid/hidraw.c b/drivers/hid/hidraw.c
index c887f48756f4..cc657d60d689 100644
--- a/drivers/hid/hidraw.c
+++ b/drivers/hid/hidraw.c
@@ -403,6 +403,8 @@ static long hidraw_ioctl(struct file *file, unsigned int cmd,
struct hidraw *dev;
struct hidraw_list *list = file->private_data;
void __user *user_arg = (void __user*) arg;
+ struct hid_device *hid;
+ int len;
down_read(&minors_rwsem);
dev = hidraw_table[minor];
@@ -453,81 +455,56 @@ static long hidraw_ioctl(struct file *file, unsigned int cmd,
break;
}
default:
- {
- struct hid_device *hid = dev->hid;
- if (_IOC_TYPE(cmd) != 'H') {
- ret = -EINVAL;
- break;
- }
-
- if (_IOC_NR(cmd) == _IOC_NR(HIDIOCSFEATURE(0))) {
- int len = _IOC_SIZE(cmd);
- ret = hidraw_send_report(file, user_arg, len, HID_FEATURE_REPORT);
- break;
- }
- if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGFEATURE(0))) {
- int len = _IOC_SIZE(cmd);
- ret = hidraw_get_report(file, user_arg, len, HID_FEATURE_REPORT);
- break;
- }
-
- if (_IOC_NR(cmd) == _IOC_NR(HIDIOCSINPUT(0))) {
- int len = _IOC_SIZE(cmd);
- ret = hidraw_send_report(file, user_arg, len, HID_INPUT_REPORT);
- break;
- }
- if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGINPUT(0))) {
- int len = _IOC_SIZE(cmd);
- ret = hidraw_get_report(file, user_arg, len, HID_INPUT_REPORT);
- break;
- }
-
- if (_IOC_NR(cmd) == _IOC_NR(HIDIOCSOUTPUT(0))) {
- int len = _IOC_SIZE(cmd);
- ret = hidraw_send_report(file, user_arg, len, HID_OUTPUT_REPORT);
- break;
- }
- if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGOUTPUT(0))) {
- int len = _IOC_SIZE(cmd);
- ret = hidraw_get_report(file, user_arg, len, HID_OUTPUT_REPORT);
- break;
- }
-
- /* Begin Read-only ioctls. */
- if (_IOC_DIR(cmd) != _IOC_READ) {
- ret = -EINVAL;
- break;
- }
-
- if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGRAWNAME(0))) {
- int len = strlen(hid->name) + 1;
- if (len > _IOC_SIZE(cmd))
- len = _IOC_SIZE(cmd);
- ret = copy_to_user(user_arg, hid->name, len) ?
- -EFAULT : len;
- break;
- }
-
- if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGRAWPHYS(0))) {
- int len = strlen(hid->phys) + 1;
- if (len > _IOC_SIZE(cmd))
- len = _IOC_SIZE(cmd);
- ret = copy_to_user(user_arg, hid->phys, len) ?
- -EFAULT : len;
- break;
- }
-
- if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGRAWUNIQ(0))) {
- int len = strlen(hid->uniq) + 1;
- if (len > _IOC_SIZE(cmd))
- len = _IOC_SIZE(cmd);
- ret = copy_to_user(user_arg, hid->uniq, len) ?
- -EFAULT : len;
- break;
- }
- }
+ break;
+ }
+ hid = dev->hid;
+ switch (cmd & ~IOCSIZE_MASK) {
+ case HIDIOCSFEATURE(0):
+ len = _IOC_SIZE(cmd);
+ ret = hidraw_send_report(file, user_arg, len, HID_FEATURE_REPORT);
+ break;
+ case HIDIOCGFEATURE(0):
+ len = _IOC_SIZE(cmd);
+ ret = hidraw_get_report(file, user_arg, len, HID_FEATURE_REPORT);
+ break;
+ case HIDIOCSINPUT(0):
+ len = _IOC_SIZE(cmd);
+ ret = hidraw_send_report(file, user_arg, len, HID_INPUT_REPORT);
+ break;
+ case HIDIOCGINPUT(0):
+ len = _IOC_SIZE(cmd);
+ ret = hidraw_get_report(file, user_arg, len, HID_INPUT_REPORT);
+ break;
+ case HIDIOCSOUTPUT(0):
+ len = _IOC_SIZE(cmd);
+ ret = hidraw_send_report(file, user_arg, len, HID_OUTPUT_REPORT);
+ break;
+ case HIDIOCGOUTPUT(0):
+ len = _IOC_SIZE(cmd);
+ ret = hidraw_get_report(file, user_arg, len, HID_OUTPUT_REPORT);
+ break;
+ case HIDIOCGRAWNAME(0):
+ len = strlen(hid->name) + 1;
+ if (len > _IOC_SIZE(cmd))
+ len = _IOC_SIZE(cmd);
+ ret = copy_to_user(user_arg, hid->name, len) ? -EFAULT : len;
+ break;
+ case HIDIOCGRAWPHYS(0):
+ len = strlen(hid->phys) + 1;
+ if (len > _IOC_SIZE(cmd))
+ len = _IOC_SIZE(cmd);
+ ret = copy_to_user(user_arg, hid->phys, len) ? -EFAULT : len;
+ break;
+ case HIDIOCGRAWUNIQ(0):
+ len = strlen(hid->uniq) + 1;
+ if (len > _IOC_SIZE(cmd))
+ len = _IOC_SIZE(cmd);
+ ret = copy_to_user(user_arg, hid->uniq, len) ? -EFAULT : len;
+ break;
+ default:
ret = -ENOTTY;
+ break;
}
out:
up_read(&minors_rwsem);
--
2.39.5
next reply other threads:[~2025-07-11 7:28 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-07-11 7:28 Arnd Bergmann [this message]
2025-07-11 9:40 ` [PATCH] HID: tighten ioctl command parsing Benjamin Tissoires
2025-07-11 10:01 ` Arnd Bergmann
2025-08-21 8:16 ` Benjamin Tissoires
2025-08-21 6:56 ` Benjamin Tissoires
2025-08-22 21:08 ` Arnd Bergmann
2025-08-26 10:13 ` Benjamin Tissoires
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