Commit f90bf1ec authored by Phong Tran's avatar Phong Tran Committed by Greg Kroah-Hartman

usb: wusbcore: fix unbalanced get/put cluster_id

syzboot reported that
https://syzkaller.appspot.com/bug?extid=fd2bd7df88c606eea4ef

There is not consitency parameter in cluste_id_get/put calling.
In case of getting the id with result is failure, the wusbhc->cluster_id
will not be updated and this can not be used for wusb_cluster_id_put().

Tested report
https://groups.google.com/d/msg/syzkaller-bugs/0znZopp3-9k/oxOrhLkLEgAJ

Reproduce and gdb got the details:

139		addr = wusb_cluster_id_get();
(gdb) n
140		if (addr == 0)
(gdb) print addr
$1 = 254 '\376'
(gdb) n
142		result = __hwahc_set_cluster_id(hwahc, addr);
(gdb) print result
$2 = -71
(gdb) break wusb_cluster_id_put
Breakpoint 3 at 0xffffffff836e3f20: file drivers/usb/wusbcore/wusbhc.c, line 384.
(gdb) s
Thread 2 hit Breakpoint 3, wusb_cluster_id_put (id=0 '\000') at drivers/usb/wusbcore/wusbhc.c:384
384		id = 0xff - id;
(gdb) n
385		BUG_ON(id >= CLUSTER_IDS);
(gdb) print id
$3 = 255 '\377'

Reported-by: syzbot+fd2bd7df88c606eea4ef@syzkaller.appspotmail.com
Signed-off-by: default avatarPhong Tran <tranmanphong@gmail.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20190724020601.15257-1-tranmanphong@gmail.comSigned-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 94b9a70d
......@@ -159,7 +159,7 @@ static int hwahc_op_start(struct usb_hcd *usb_hcd)
return result;
error_set_cluster_id:
wusb_cluster_id_put(wusbhc->cluster_id);
wusb_cluster_id_put(addr);
error_cluster_id_get:
goto out;
......
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