diff options
| author | Aleksa Savic <savicaleksa83@gmail.com> | 2024-05-04 11:25:03 +0200 |
|---|---|---|
| committer | Guenter Roeck <linux@roeck-us.net> | 2024-05-04 06:36:41 -0700 |
| commit | d02abd57e79469a026213f7f5827a98d909f236a (patch) | |
| tree | e31c063e32acc4688f3d6a0351c6cae011c0ce3c /drivers/hwmon | |
| parent | 3a034a7b0715eb51124a5263890b1ed39978ed3a (diff) | |
| download | linux-d02abd57e79469a026213f7f5827a98d909f236a.tar.gz | |
hwmon: (corsair-cpro) Protect ccp->wait_input_report with a spinlock
Through hidraw, userspace can cause a status report to be sent
from the device. The parsing in ccp_raw_event() may happen in
parallel to a send_usb_cmd() call (which resets the completion
for tracking the report) if it's running on a different CPU where
bottom half interrupts are not disabled.
Add a spinlock around the complete_all() in ccp_raw_event() and
reinit_completion() in send_usb_cmd() to prevent race issues.
Fixes: 40c3a4454225 ("hwmon: add Corsair Commander Pro driver")
Signed-off-by: Aleksa Savic <savicaleksa83@gmail.com>
Acked-by: Marius Zachmann <mail@mariuszachmann.de>
Link: https://lore.kernel.org/r/20240504092504.24158-4-savicaleksa83@gmail.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Diffstat (limited to 'drivers/hwmon')
| -rw-r--r-- | drivers/hwmon/corsair-cpro.c | 24 |
1 files changed, 19 insertions, 5 deletions
diff --git a/drivers/hwmon/corsair-cpro.c b/drivers/hwmon/corsair-cpro.c index 6ab4d2478b1fd6..3e63666a61bd6b 100644 --- a/drivers/hwmon/corsair-cpro.c +++ b/drivers/hwmon/corsair-cpro.c @@ -16,6 +16,7 @@ #include <linux/module.h> #include <linux/mutex.h> #include <linux/slab.h> +#include <linux/spinlock.h> #include <linux/types.h> #define USB_VENDOR_ID_CORSAIR 0x1b1c @@ -77,6 +78,8 @@ struct ccp_device { struct hid_device *hdev; struct device *hwmon_dev; + /* For reinitializing the completion below */ + spinlock_t wait_input_report_lock; struct completion wait_input_report; struct mutex mutex; /* whenever buffer is used, lock before send_usb_cmd */ u8 *cmd_buffer; @@ -118,7 +121,15 @@ static int send_usb_cmd(struct ccp_device *ccp, u8 command, u8 byte1, u8 byte2, ccp->cmd_buffer[2] = byte2; ccp->cmd_buffer[3] = byte3; + /* + * Disable raw event parsing for a moment to safely reinitialize the + * completion. Reinit is done because hidraw could have triggered + * the raw event parsing and marked the ccp->wait_input_report + * completion as done. + */ + spin_lock_bh(&ccp->wait_input_report_lock); reinit_completion(&ccp->wait_input_report); + spin_unlock_bh(&ccp->wait_input_report_lock); ret = hid_hw_output_report(ccp->hdev, ccp->cmd_buffer, OUT_BUFFER_SIZE); if (ret < 0) @@ -136,11 +147,12 @@ static int ccp_raw_event(struct hid_device *hdev, struct hid_report *report, u8 struct ccp_device *ccp = hid_get_drvdata(hdev); /* only copy buffer when requested */ - if (completion_done(&ccp->wait_input_report)) - return 0; - - memcpy(ccp->buffer, data, min(IN_BUFFER_SIZE, size)); - complete_all(&ccp->wait_input_report); + spin_lock(&ccp->wait_input_report_lock); + if (!completion_done(&ccp->wait_input_report)) { + memcpy(ccp->buffer, data, min(IN_BUFFER_SIZE, size)); + complete_all(&ccp->wait_input_report); + } + spin_unlock(&ccp->wait_input_report_lock); return 0; } @@ -515,7 +527,9 @@ static int ccp_probe(struct hid_device *hdev, const struct hid_device_id *id) ccp->hdev = hdev; hid_set_drvdata(hdev, ccp); + mutex_init(&ccp->mutex); + spin_lock_init(&ccp->wait_input_report_lock); init_completion(&ccp->wait_input_report); hid_device_io_start(hdev); |