From: Udipto Goswami <quic_ugoswami@xxxxxxxxxxx>
[ 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@xxxxxxxxxxxx>
Signed-off-by: Udipto Goswami <quic_ugoswami@xxxxxxxxxxx>
Link: https://lore.kernel.org/r/20230124091149.18647-1-quic_ugoswami@xxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/usb/gadget/function/f_fs.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c
index 94000fd190e5..8c48c9f801be 100644
--- a/drivers/usb/gadget/function/f_fs.c
+++ b/drivers/usb/gadget/function/f_fs.c
@@ -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);
--
2.39.0
