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| author | Alan Stern <stern@rowland.harvard.edu> | 2019-10-03 14:53:59 -0400 |
|---|---|---|
| committer | Benjamin Tissoires <benjamin.tissoires@redhat.com> | 2019-10-03 15:36:40 -0400 |
| commit | d9d4b1e46d9543a82c23f6df03f4ad697dab361b (patch) | |
| tree | 5a405a2f78b1029f4cc6d6ee743f0bec31319b42 /drivers/hid/hid-axff.c | |
| parent | fe2199cfd1516e90e03c033c52c9a28da09d9986 (diff) | |
| download | linux-d9d4b1e46d9543a82c23f6df03f4ad697dab361b.tar.gz | |
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-axff.c')
| -rw-r--r-- | drivers/hid/hid-axff.c | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/drivers/hid/hid-axff.c b/drivers/hid/hid-axff.c index 6654c1550e2e..fbe4e16ab029 100644 --- a/drivers/hid/hid-axff.c +++ b/drivers/hid/hid-axff.c @@ -63,13 +63,20 @@ static int axff_init(struct hid_device *hid) { 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; |