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| author | Alan Stern <stern@rowland.harvard.edu> | 2019-10-03 21:53:59 +0300 |
|---|---|---|
| committer | Benjamin Tissoires <benjamin.tissoires@redhat.com> | 2019-10-03 22:36:40 +0300 |
| commit | d9d4b1e46d9543a82c23f6df03f4ad697dab361b (patch) | |
| tree | 5a405a2f78b1029f4cc6d6ee743f0bec31319b42 /drivers/hid/hid-microsoft.c | |
| parent | fe2199cfd1516e90e03c033c52c9a28da09d9986 (diff) | |
| download | linux-d9d4b1e46d9543a82c23f6df03f4ad697dab361b.tar.xz | |
HID: Fix assumption that devices have inputs
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@syzkaller.appspotmail.com
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
CC: <stable@vger.kernel.org>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Diffstat (limited to 'drivers/hid/hid-microsoft.c')
| -rw-r--r-- | drivers/hid/hid-microsoft.c | 12 |
1 files changed, 9 insertions, 3 deletions
diff --git a/drivers/hid/hid-microsoft.c b/drivers/hid/hid-microsoft.c index 2cf83856f2e4..2d8b589201a4 100644 --- a/drivers/hid/hid-microsoft.c +++ b/drivers/hid/hid-microsoft.c @@ -328,11 +328,17 @@ static int ms_play_effect(struct input_dev *dev, void *data, static int ms_init_ff(struct hid_device *hdev) { - struct hid_input *hidinput = list_entry(hdev->inputs.next, - struct hid_input, list); - struct input_dev *input_dev = hidinput->input; + struct hid_input *hidinput; + struct input_dev *input_dev; struct ms_data *ms = hid_get_drvdata(hdev); + if (list_empty(&hdev->inputs)) { + hid_err(hdev, "no inputs found\n"); + return -ENODEV; + } + hidinput = list_entry(hdev->inputs.next, struct hid_input, list); + input_dev = hidinput->input; + if (!(ms->quirks & MS_QUIRK_FF)) return 0; |