[PATCH AUTOSEL 5.18 086/159] HID: bigben: fix slab-out-of-bounds Write in bigben_probe

Sasha Levin
2022-05-30T13:41:24Z

From: Dongliang Mu <mudongliangabcd@gmail.com>

[ Upstream commit fc4ef9d5724973193bfa5ebed181dba6de3a56db ]

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 <syzkaller@googlegroups.com>
Signed-off-by: Dongliang Mu <mudongliangabcd@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
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);

--
2.35.1