5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Chen Changcheng commit d3aba3442798ce4a4c8ce3104d7b286d61e605f9 upstream. alps_input_configured() stores data->input2 before calling input_register_device(). If registration fails, input_free_device() frees the input device but data->input2 still points to the freed memory. alps_input_configured() calls hid_hw_open() before allocating input2, so URBs are already active and raw_event can fire during the failure window. A U1_SP_ABSOLUTE_REPORT_ID report arriving then causes u1_raw_event() to dereference the freed data->input2 -> use-after-free. Fix by only storing input2 into drvdata after successful registration and adding a NULL guard in the raw_event path. Fixes: 2562756dde55 ("HID: add Alps I2C HID Touchpad-Stick support") Cc: stable@vger.kernel.org Signed-off-by: Chen Changcheng Signed-off-by: Jiri Kosina Signed-off-by: Greg Kroah-Hartman --- drivers/hid/hid-alps.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/drivers/hid/hid-alps.c +++ b/drivers/hid/hid-alps.c @@ -407,6 +407,8 @@ static int u1_raw_event(struct alps_dev return 1; case U1_SP_ABSOLUTE_REPORT_ID: + if (!hdata->input2) + return 0; sp_x = get_unaligned_le16(data+2); sp_y = get_unaligned_le16(data+4); @@ -738,7 +740,6 @@ static int alps_input_configured(struct goto exit; } - data->input2 = input2; input2->phys = input->phys; input2->name = "DualPoint Stick"; input2->id.bustype = BUS_I2C; @@ -762,11 +763,12 @@ static int alps_input_configured(struct __set_bit(INPUT_PROP_POINTER, input2->propbit); __set_bit(INPUT_PROP_POINTING_STICK, input2->propbit); - if (input_register_device(data->input2)) { + if (input_register_device(input2)) { input_free_device(input2); ret = -ENOENT; goto exit; } + data->input2 = input2; } exit: