From: Pietro Borrello borrello@diag.uniroma1.it
[ Upstream commit b12fece4c64857e5fab4290bf01b2e0317a88456 ]
Add a check for empty report_list in hid_validate_values(). The missing check causes a type confusion when issuing a list_entry() on an empty report_list. The problem is caused by the assumption that the device must have valid report_list. While this will be true for all normal HID devices, a suitably malicious device can violate the assumption.
Fixes: 1b15d2e5b807 ("HID: core: fix validation of report id 0") Signed-off-by: Pietro Borrello borrello@diag.uniroma1.it Signed-off-by: Jiri Kosina jkosina@suse.cz Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/hid/hid-core.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c index eda96c92977b..2888bd5502f3 100644 --- a/drivers/hid/hid-core.c +++ b/drivers/hid/hid-core.c @@ -981,8 +981,8 @@ struct hid_report *hid_validate_values(struct hid_device *hid, * Validating on id 0 means we should examine the first * report in the list. */ - report = list_entry( - hid->report_enum[type].report_list.next, + report = list_first_entry_or_null( + &hid->report_enum[type].report_list, struct hid_report, list); } else { report = hid->report_enum[type].report_id_hash[id];