2022-05-06 16:08:44

by Dongliang Mu

Subject: [PATCH v2] HID: bigben: fix slab-out-of-bounds Write in bigben_probe

From: Dongliang Mu <[email protected]>

There is a slab-out-of-bounds Write bug in hid-bigbenff driver.
The problem is the driver assumes the device must have an input but
some malicious devices violate this assumption.

Fix this by checking hid_device's input is non-empty before its usage.

Reported-by: syzkaller <[email protected]>
Signed-off-by: Dongliang Mu <[email protected]>
---
v1->v2: modify return directly to goto error_hw_stop;
drivers/hid/hid-bigbenff.c | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/drivers/hid/hid-bigbenff.c b/drivers/hid/hid-bigbenff.c
index 74ad8bf98bfd..e8c5e3ac9fff 100644
--- a/drivers/hid/hid-bigbenff.c
+++ b/drivers/hid/hid-bigbenff.c
@@ -347,6 +347,12 @@ static int bigben_probe(struct hid_device *hid,
bigben->report = list_entry(report_list->next,
struct hid_report, list);

+ if (list_empty(&hid->inputs)) {
+ hid_err(hid, "no inputs found\n");
+ error = -ENODEV;
+ goto error_hw_stop;
+ }
+
hidinput = list_first_entry(&hid->inputs, struct hid_input, list);
set_bit(FF_RUMBLE, hidinput->input->ffbit);

--
2.25.1

2022-05-09 06:04:29

by Jiri Kosina

Subject: Re: [PATCH v2] HID: bigben: fix slab-out-of-bounds Write in bigben_probe

On Fri, 6 May 2022, Dongliang Mu wrote:

> From: Dongliang Mu <[email protected]>
>
> There is a slab-out-of-bounds Write bug in hid-bigbenff driver.
> The problem is the driver assumes the device must have an input but
> some malicious devices violate this assumption.
>
> Fix this by checking hid_device's input is non-empty before its usage.
>
> Reported-by: syzkaller <[email protected]>
> Signed-off-by: Dongliang Mu <[email protected]>

Applied. thanks.

--
Jiri Kosina
SUSE Labs