[PATCH v1 2/2] usb: gadgetfs: Fix ep_read_iter to handle ITER_UBUF

From: Sandeep Dhavale
Date: Sat Apr 01 2023 - 02:05:54 EST


iov_iter for ep_read_iter can be ITER_UBUF with io_uring.
In that case dup_iter() does not have to allocate iov and it can
return NULL. Fix the assumption by checking for iter_is_ubuf()
other wise ep_read_iter can treat this as failure and return -ENOMEM.

Fixes: 1e23db450cff ("io_uring: use iter_ubuf for single range imports")
Signed-off-by: Sandeep Dhavale <dhavale@xxxxxxxxxx>
---
drivers/usb/gadget/legacy/inode.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/usb/gadget/legacy/inode.c b/drivers/usb/gadget/legacy/inode.c
index d605bc2e7e8f..28249d0bf062 100644
--- a/drivers/usb/gadget/legacy/inode.c
+++ b/drivers/usb/gadget/legacy/inode.c
@@ -614,7 +614,7 @@ ep_read_iter(struct kiocb *iocb, struct iov_iter *to)
if (!priv)
goto fail;
priv->to_free = dup_iter(&priv->to, to, GFP_KERNEL);
- if (!priv->to_free) {
+ if (!iter_is_ubuf(&priv->to) && !priv->to_free) {
kfree(priv);
goto fail;
}
--
2.40.0.348.gf938b09366-goog