[PATCH 4/4] usb: gadget: f_mass_storage: Fix memory leak of fsg buffers

[Mattijs Korpershoek]

In fsg_common_init, we allocate some buffers via memalign().
However, these buffers are never freed.

Because of that, we cannot call => ums command multiple times on boards
with low memory (CONFIG_SYS_MALLOC_LEN=0x81000):

=> ums 0 mmc 2
UMS: LUN 0, dev mmc 2, hwpart 0, sector 0x0, count 0x3a3e000
|crq->brequest:0x0
CTRL+C - Operation aborted
=> ums 0 mmc 2
UMS: LUN 0, dev mmc 2, hwpart 0, sector 0x0, count 0x3a3e000
failed to start <NULL>: -12
g_dnl_register: failed!, error: -12
g_dnl_register failed

Make sure the fsg buffers are freed when the gadget is unbound by
calling fsg_common_release() in fsg_unbind().

Reported-by: Zixun LI <ad...@hifiphile.com>
Signed-off-by: Mattijs Korpershoek <mkorpersh...@baylibre.com>
---
 drivers/usb/gadget/f_mass_storage.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/usb/gadget/f_mass_storage.c 
b/drivers/usb/gadget/f_mass_storage.c
index fcce6d12f56b..71dc58da3f03 100644
--- a/drivers/usb/gadget/f_mass_storage.c
+++ b/drivers/usb/gadget/f_mass_storage.c
@@ -2639,6 +2639,7 @@ static void fsg_unbind(struct usb_configuration *c, 
struct usb_function *f)
                raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
        }
 
+       fsg_common_release(fsg->common);
        free(fsg->function.descriptors);
        free(fsg->function.hs_descriptors);
        kfree(fsg);

-- 
2.49.0