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authorAnirudh Rayabharam <mail@anirudhrb.com>2021-04-25 20:33:53 +0300
committerJiri Kosina <jkosina@suse.cz>2021-05-05 16:52:34 +0300
commit6be388f4a35d2ce5ef7dbf635a8964a5da7f799f (patch)
tree6e4a7f2bd3471fa91be4a74f4eeafe49d77598eb /include/linux/hid.h
parent48e33befe61a7d407753c53d1a06fc8d6b5dab80 (diff)
downloadlinux-6be388f4a35d2ce5ef7dbf635a8964a5da7f799f.tar.xz
HID: usbhid: fix info leak in hid_submit_ctrl
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>
Diffstat (limited to 'include/linux/hid.h')
-rw-r--r--include/linux/hid.h3
1 files changed, 1 insertions, 2 deletions
diff --git a/include/linux/hid.h b/include/linux/hid.h
index 271021e20a3f..10e922cee4eb 100644
--- a/include/linux/hid.h
+++ b/include/linux/hid.h
@@ -1167,8 +1167,7 @@ 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,