usb: gadget: f_fs: Fix unbalanced spinlock in __ffs_ep0_queue_wait

[ Upstream commit 921deb9da15851425ccbb6ee409dc2fd8fbdfe6b ]

__ffs_ep0_queue_wait executes holding the spinlock of &ffs->ev.waitq.lock
and unlocks it after the assignments to usb_request are done.
However in the code if the request is already NULL we bail out returning
-EINVAL but never unlocked the spinlock.

Fix this by adding spin_unlock_irq &ffs->ev.waitq.lock before returning.

Fixes: 6a19da111057 ("usb: gadget: f_fs: Prevent race during ffs_ep0_queue_wait")
Reviewed-by: John Keeping <john@metanate.com>
Signed-off-by: Udipto Goswami <quic_ugoswami@quicinc.com>
Link: https://lore.kernel.org/r/20230124091149.18647-1-quic_ugoswami@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Udipto Goswami 2023-01-24 14:41:49 +05:30 committed by Greg Kroah-Hartman
parent db3798943a
commit 5bf0010b87

View File

@ -278,8 +278,10 @@ static int __ffs_ep0_queue_wait(struct ffs_data *ffs, char *data, size_t len)
struct usb_request *req = ffs->ep0req;
int ret;
if (!req)
if (!req) {
spin_unlock_irq(&ffs->ev.waitq.lock);
return -EINVAL;
}
req->zero = len < le16_to_cpu(ffs->ev.setup.wLength);