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| author | Anirudh Rayabharam <mail@anirudhrb.com> | 2021-04-25 20:33:53 +0300 |
|---|---|---|
| committer | Sasha Levin <sashal@kernel.org> | 2021-06-30 15:48:45 +0300 |
| commit | 8c064eece9a51856f3f275104520c7e3017fc5c0 (patch) | |
| tree | 0dd5ee04d297a6b9338c9894915574ce14e789cb /include | |
| parent | 43ab41d973e3e3be389a2819477d8054b9e61903 (diff) | |
| download | linux-8c064eece9a51856f3f275104520c7e3017fc5c0.tar.xz | |
HID: usbhid: fix info leak in hid_submit_ctrl
[ 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>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/hid.h | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/include/linux/hid.h b/include/linux/hid.h index d07fe33a9045..5a2c55ed33fa 100644 --- a/include/linux/hid.h +++ b/include/linux/hid.h @@ -1114,8 +1114,7 @@ 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, |