This is a note to let you know that I've just added the patch titled HID: betop: check shape of output reports to the 5.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: hid-betop-check-shape-of-output-reports.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit c8d5817a7e586572fa924671fc6580098efa4059 Author: Pietro Borrello <borrello@xxxxxxxxxxxxxxxx> Date: Wed Jan 11 18:12:16 2023 +0000 HID: betop: check shape of output reports [ Upstream commit 3782c0d6edf658b71354a64d60aa7a296188fc90 ] betopff_init() only checks the total sum of the report counts for each report field to be at least 4, but hid_betopff_play() expects 4 report fields. A device advertising an output report with one field and 4 report counts would pass the check but crash the kernel with a NULL pointer dereference in hid_betopff_play(). Fixes: 52cd7785f3cd ("HID: betop: add drivers/hid/hid-betopff.c") Signed-off-by: Pietro Borrello <borrello@xxxxxxxxxxxxxxxx> Signed-off-by: Jiri Kosina <jkosina@xxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/hid/hid-betopff.c b/drivers/hid/hid-betopff.c index 467d789f9bc2..25ed7b9a917e 100644 --- a/drivers/hid/hid-betopff.c +++ b/drivers/hid/hid-betopff.c @@ -60,7 +60,6 @@ static int betopff_init(struct hid_device *hid) struct list_head *report_list = &hid->report_enum[HID_OUTPUT_REPORT].report_list; struct input_dev *dev; - int field_count = 0; int error; int i, j; @@ -86,19 +85,21 @@ static int betopff_init(struct hid_device *hid) * ----------------------------------------- * Do init them with default value. */ + if (report->maxfield < 4) { + hid_err(hid, "not enough fields in the report: %d\n", + report->maxfield); + return -ENODEV; + } for (i = 0; i < report->maxfield; i++) { + if (report->field[i]->report_count < 1) { + hid_err(hid, "no values in the field\n"); + return -ENODEV; + } for (j = 0; j < report->field[i]->report_count; j++) { report->field[i]->value[j] = 0x00; - field_count++; } } - if (field_count < 4) { - hid_err(hid, "not enough fields in the report: %d\n", - field_count); - return -ENODEV; - } - betopff = kzalloc(sizeof(*betopff), GFP_KERNEL); if (!betopff) return -ENOMEM;