From 1547d41f9f19d691c2c9ce4c29f746297baef9e9 Mon Sep 17 00:00:00 2001 From: =?utf8?q?G=C3=BCnther=20Noack?= Date: Fri, 9 Jan 2026 13:25:58 +0100 Subject: [PATCH] HID: logitech-hidpp: Check maxfield in hidpp_get_report_length() MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Do not crash when a report has no fields. Fake USB gadgets can send their own HID report descriptors and can define report structures without valid fields. This can be used to crash the kernel over USB. Cc: stable@vger.kernel.org Signed-off-by: Günther Noack Signed-off-by: Jiri Kosina --- drivers/hid/hid-logitech-hidpp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/hid/hid-logitech-hidpp.c b/drivers/hid/hid-logitech-hidpp.c index e871f1729d4b3..d0a38eff9cfa8 100644 --- a/drivers/hid/hid-logitech-hidpp.c +++ b/drivers/hid/hid-logitech-hidpp.c @@ -4314,7 +4314,7 @@ static int hidpp_get_report_length(struct hid_device *hdev, int id) re = &(hdev->report_enum[HID_OUTPUT_REPORT]); report = re->report_id_hash[id]; - if (!report) + if (!report || !report->maxfield) return 0; return report->field[0]->report_count + 1; -- 2.47.3