6.12-stable review patch. If anyone has any objections, please let me know.
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From: Marius Zachmann mail@mariuszachmann.de
[ Upstream commit 495a4f0dce9c8c4478c242209748f1ee9e4d5820 ]
Add buffer_recv_size to store the size of the received bytes. Validate buffer_recv_size in send_usb_cmd().
Reported-by: syzbot+3bbbade4e1a7ab45ca3b@syzkaller.appspotmail.com Closes: https://lore.kernel.org/linux-hwmon/61233ba1-e5ad-4d7a-ba31-3b5d0adcffcc@roe... Fixes: 40c3a4454225 ("hwmon: add Corsair Commander Pro driver") Signed-off-by: Marius Zachmann mail@mariuszachmann.de Link: https://lore.kernel.org/r/20250619132817.39764-5-mail@mariuszachmann.de Signed-off-by: Guenter Roeck linux@roeck-us.net Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/hwmon/corsair-cpro.c | 5 +++++ 1 file changed, 5 insertions(+)
diff --git a/drivers/hwmon/corsair-cpro.c b/drivers/hwmon/corsair-cpro.c index e1a7f7aa7f804..b7b911f8359c7 100644 --- a/drivers/hwmon/corsair-cpro.c +++ b/drivers/hwmon/corsair-cpro.c @@ -89,6 +89,7 @@ struct ccp_device { struct mutex mutex; /* whenever buffer is used, lock before send_usb_cmd */ u8 *cmd_buffer; u8 *buffer; + int buffer_recv_size; /* number of received bytes in buffer */ int target[6]; DECLARE_BITMAP(temp_cnct, NUM_TEMP_SENSORS); DECLARE_BITMAP(fan_cnct, NUM_FANS); @@ -146,6 +147,9 @@ static int send_usb_cmd(struct ccp_device *ccp, u8 command, u8 byte1, u8 byte2, if (!t) return -ETIMEDOUT;
+ if (ccp->buffer_recv_size != IN_BUFFER_SIZE) + return -EPROTO; + return ccp_get_errno(ccp); }
@@ -157,6 +161,7 @@ static int ccp_raw_event(struct hid_device *hdev, struct hid_report *report, u8 spin_lock(&ccp->wait_input_report_lock); if (!completion_done(&ccp->wait_input_report)) { memcpy(ccp->buffer, data, min(IN_BUFFER_SIZE, size)); + ccp->buffer_recv_size = size; complete_all(&ccp->wait_input_report); } spin_unlock(&ccp->wait_input_report_lock);