3.16.79-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> commit d9d4b1e46d9543a82c23f6df03f4ad697dab361b upstream. The syzbot fuzzer found a slab-out-of-bounds write bug in the hid-gaff driver. The problem is caused by the driver's assumption that the device must have an input report. While this will be true for all normal HID input devices, a suitably malicious device can violate the assumption. The same assumption is present in over a dozen other HID drivers. This patch fixes them by checking that the list of hid_inputs for the hid_device is nonempty before allowing it to be used. Reported-and-tested-by: syzbot+403741a091bf41d4ae79@xxxxxxxxxxxxxxxxxxxxxxxxx Signed-off-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Benjamin Tissoires <benjamin.tissoires@xxxxxxxxxx> [bwh: Backported to 3.16: - Drop changes in hid-logitech-hidpp, hid-microsoft - Adjust context] Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx> --- --- a/drivers/hid/hid-axff.c +++ b/drivers/hid/hid-axff.c @@ -75,13 +75,20 @@ static int axff_init(struct hid_device * { struct axff_device *axff; struct hid_report *report; - struct hid_input *hidinput = list_first_entry(&hid->inputs, struct hid_input, list); + struct hid_input *hidinput; struct list_head *report_list =&hid->report_enum[HID_OUTPUT_REPORT].report_list; - struct input_dev *dev = hidinput->input; + struct input_dev *dev; int field_count = 0; int i, j; int error; + if (list_empty(&hid->inputs)) { + hid_err(hid, "no inputs found\n"); + return -ENODEV; + } + hidinput = list_first_entry(&hid->inputs, struct hid_input, list); + dev = hidinput->input; + if (list_empty(report_list)) { hid_err(hid, "no output reports found\n"); return -ENODEV; --- a/drivers/hid/hid-dr.c +++ b/drivers/hid/hid-dr.c @@ -87,13 +87,19 @@ static int drff_init(struct hid_device * { struct drff_device *drff; struct hid_report *report; - struct hid_input *hidinput = list_first_entry(&hid->inputs, - struct hid_input, list); + struct hid_input *hidinput; struct list_head *report_list = &hid->report_enum[HID_OUTPUT_REPORT].report_list; - struct input_dev *dev = hidinput->input; + struct input_dev *dev; int error; + if (list_empty(&hid->inputs)) { + hid_err(hid, "no inputs found\n"); + return -ENODEV; + } + hidinput = list_first_entry(&hid->inputs, struct hid_input, list); + dev = hidinput->input; + if (list_empty(report_list)) { hid_err(hid, "no output reports found\n"); return -ENODEV; --- a/drivers/hid/hid-emsff.c +++ b/drivers/hid/hid-emsff.c @@ -59,13 +59,19 @@ static int emsff_init(struct hid_device { struct emsff_device *emsff; struct hid_report *report; - struct hid_input *hidinput = list_first_entry(&hid->inputs, - struct hid_input, list); + struct hid_input *hidinput; struct list_head *report_list = &hid->report_enum[HID_OUTPUT_REPORT].report_list; - struct input_dev *dev = hidinput->input; + struct input_dev *dev; int error; + if (list_empty(&hid->inputs)) { + hid_err(hid, "no inputs found\n"); + return -ENODEV; + } + hidinput = list_first_entry(&hid->inputs, struct hid_input, list); + dev = hidinput->input; + if (list_empty(report_list)) { hid_err(hid, "no output reports found\n"); return -ENODEV; --- a/drivers/hid/hid-gaff.c +++ b/drivers/hid/hid-gaff.c @@ -77,14 +77,20 @@ static int gaff_init(struct hid_device * { struct gaff_device *gaff; struct hid_report *report; - struct hid_input *hidinput = list_entry(hid->inputs.next, - struct hid_input, list); + struct hid_input *hidinput; struct list_head *report_list = &hid->report_enum[HID_OUTPUT_REPORT].report_list; struct list_head *report_ptr = report_list; - struct input_dev *dev = hidinput->input; + struct input_dev *dev; int error; + if (list_empty(&hid->inputs)) { + hid_err(hid, "no inputs found\n"); + return -ENODEV; + } + hidinput = list_entry(hid->inputs.next, struct hid_input, list); + dev = hidinput->input; + if (list_empty(report_list)) { hid_err(hid, "no output reports found\n"); return -ENODEV; --- a/drivers/hid/hid-holtekff.c +++ b/drivers/hid/hid-holtekff.c @@ -140,13 +140,19 @@ static int holtekff_init(struct hid_devi { struct holtekff_device *holtekff; struct hid_report *report; - struct hid_input *hidinput = list_entry(hid->inputs.next, - struct hid_input, list); + struct hid_input *hidinput; struct list_head *report_list = &hid->report_enum[HID_OUTPUT_REPORT].report_list; - struct input_dev *dev = hidinput->input; + struct input_dev *dev; int error; + if (list_empty(&hid->inputs)) { + hid_err(hid, "no inputs found\n"); + return -ENODEV; + } + hidinput = list_entry(hid->inputs.next, struct hid_input, list); + dev = hidinput->input; + if (list_empty(report_list)) { hid_err(hid, "no output report found\n"); return -ENODEV; --- a/drivers/hid/hid-lg2ff.c +++ b/drivers/hid/hid-lg2ff.c @@ -62,11 +62,17 @@ int lg2ff_init(struct hid_device *hid) { struct lg2ff_device *lg2ff; struct hid_report *report; - struct hid_input *hidinput = list_entry(hid->inputs.next, - struct hid_input, list); - struct input_dev *dev = hidinput->input; + struct hid_input *hidinput; + struct input_dev *dev; int error; + if (list_empty(&hid->inputs)) { + hid_err(hid, "no inputs found\n"); + return -ENODEV; + } + hidinput = list_entry(hid->inputs.next, struct hid_input, list); + dev = hidinput->input; + /* Check that the report looks ok */ report = hid_validate_values(hid, HID_OUTPUT_REPORT, 0, 0, 7); if (!report) --- a/drivers/hid/hid-lg3ff.c +++ b/drivers/hid/hid-lg3ff.c @@ -129,12 +129,19 @@ static const signed short ff3_joystick_a int lg3ff_init(struct hid_device *hid) { - struct hid_input *hidinput = list_entry(hid->inputs.next, struct hid_input, list); - struct input_dev *dev = hidinput->input; + struct hid_input *hidinput; + struct input_dev *dev; const signed short *ff_bits = ff3_joystick_ac; int error; int i; + if (list_empty(&hid->inputs)) { + hid_err(hid, "no inputs found\n"); + return -ENODEV; + } + hidinput = list_entry(hid->inputs.next, struct hid_input, list); + dev = hidinput->input; + /* Check that the report looks ok */ if (!hid_validate_values(hid, HID_OUTPUT_REPORT, 0, 0, 35)) return -ENODEV; --- a/drivers/hid/hid-lg4ff.c +++ b/drivers/hid/hid-lg4ff.c @@ -558,14 +558,21 @@ static enum led_brightness lg4ff_led_get int lg4ff_init(struct hid_device *hid) { - struct hid_input *hidinput = list_entry(hid->inputs.next, struct hid_input, list); - struct input_dev *dev = hidinput->input; + struct hid_input *hidinput; + struct input_dev *dev; struct lg4ff_device_entry *entry; struct lg_drv_data *drv_data; struct usb_device_descriptor *udesc; int error, i, j; __u16 bcdDevice, rev_maj, rev_min; + if (list_empty(&hid->inputs)) { + hid_err(hid, "no inputs found\n"); + return -ENODEV; + } + hidinput = list_entry(hid->inputs.next, struct hid_input, list); + dev = hidinput->input; + /* Check that the report looks ok */ if (!hid_validate_values(hid, HID_OUTPUT_REPORT, 0, 0, 7)) return -1; --- a/drivers/hid/hid-lgff.c +++ b/drivers/hid/hid-lgff.c @@ -127,12 +127,19 @@ static void hid_lgff_set_autocenter(stru int lgff_init(struct hid_device* hid) { - struct hid_input *hidinput = list_entry(hid->inputs.next, struct hid_input, list); - struct input_dev *dev = hidinput->input; + struct hid_input *hidinput; + struct input_dev *dev; const signed short *ff_bits = ff_joystick; int error; int i; + if (list_empty(&hid->inputs)) { + hid_err(hid, "no inputs found\n"); + return -ENODEV; + } + hidinput = list_entry(hid->inputs.next, struct hid_input, list); + dev = hidinput->input; + /* Check that the report looks ok */ if (!hid_validate_values(hid, HID_OUTPUT_REPORT, 0, 0, 7)) return -ENODEV; --- a/drivers/hid/hid-sony.c +++ b/drivers/hid/hid-sony.c @@ -1509,9 +1509,15 @@ static int sony_play_effect(struct input static int sony_init_ff(struct sony_sc *sc) { - struct hid_input *hidinput = list_entry(sc->hdev->inputs.next, - struct hid_input, list); - struct input_dev *input_dev = hidinput->input; + struct hid_input *hidinput; + struct input_dev *input_dev; + + if (list_empty(&sc->hdev->inputs)) { + hid_err(sc->hdev, "no inputs found\n"); + return -ENODEV; + } + hidinput = list_entry(sc->hdev->inputs.next, struct hid_input, list); + input_dev = hidinput->input; input_set_capability(input_dev, EV_FF, FF_RUMBLE); return input_ff_create_memless(input_dev, NULL, sony_play_effect); --- a/drivers/hid/hid-tmff.c +++ b/drivers/hid/hid-tmff.c @@ -126,12 +126,18 @@ static int tmff_init(struct hid_device * struct tmff_device *tmff; struct hid_report *report; struct list_head *report_list; - struct hid_input *hidinput = list_entry(hid->inputs.next, - struct hid_input, list); - struct input_dev *input_dev = hidinput->input; + struct hid_input *hidinput; + struct input_dev *input_dev; int error; int i; + if (list_empty(&hid->inputs)) { + hid_err(hid, "no inputs found\n"); + return -ENODEV; + } + hidinput = list_entry(hid->inputs.next, struct hid_input, list); + input_dev = hidinput->input; + tmff = kzalloc(sizeof(struct tmff_device), GFP_KERNEL); if (!tmff) return -ENOMEM; --- a/drivers/hid/hid-zpff.c +++ b/drivers/hid/hid-zpff.c @@ -66,11 +66,17 @@ static int zpff_init(struct hid_device * { struct zpff_device *zpff; struct hid_report *report; - struct hid_input *hidinput = list_entry(hid->inputs.next, - struct hid_input, list); - struct input_dev *dev = hidinput->input; + struct hid_input *hidinput; + struct input_dev *dev; int i, error; + if (list_empty(&hid->inputs)) { + hid_err(hid, "no inputs found\n"); + return -ENODEV; + } + hidinput = list_entry(hid->inputs.next, struct hid_input, list); + dev = hidinput->input; + for (i = 0; i < 4; i++) { report = hid_validate_values(hid, HID_OUTPUT_REPORT, 0, i, 1); if (!report)