xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

HID: usbhid: fix info leak in hid_submit_ctrl

Browse Source 
[ Upstream commit 6be388f4a35d2ce5ef7dbf635a8964a5da7f799f ]

In hid_submit_ctrl(), the way of calculating the report length doesn't
take into account that report->size can be zero. When running the
syzkaller reproducer, a report of size 0 causes hid_submit_ctrl) to
calculate transfer_buffer_length as 16384. When this urb is passed to
the usb core layer, KMSAN reports an info leak of 16384 bytes.

To fix this, first modify hid_report_len() to account for the zero
report size case by using DIV_ROUND_UP for the division. Then, call it
from hid_submit_ctrl().

Reported-by: syzbot+7c2bb71996f95a82524c@syzkaller.appspotmail.com
Signed-off-by: Anirudh Rayabharam <mail@anirudhrb.com>
Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Anirudh Rayabharam
2021-04-25 23:03:53 +05:30
committed by Greg Kroah-Hartman
parent 1dfd9f18ca
commit b1e3596416
2 changed files with 2 additions and 3 deletions
Download Patch File Download Diff File Expand all files Collapse all files

3
include/linux/hid.h
View File

@@ -1156,8 +1156,7 @@ static inline void hid_hw_wait(struct hid_device *hdev)
*/
static inline u32 hid_report_len(struct hid_report *report)
{
/* equivalent to DIV_ROUND_UP(report->size, 8) + !!(report->id > 0) */
return ((report->size - 1) >> 3) + 1 + (report->id > 0);
return DIV_ROUND_UP(report->size, 8) + (report->id > 0);
}
int hid_report_raw_event(struct hid_device *hid, int type, u8 *data, u32 size,