usb: musb: Fix runtime PM imbalance on error

commit e4befc121d upstream.

When copy_from_user() returns an error code, there
is a runtime PM usage counter imbalance.

Fix this by moving copy_from_user() to the beginning
of this function.

Fixes: 7b6c1b4c0e ("usb: musb: fix runtime PM in debugfs")

Signed-off-by: Dinghao Liu <dinghao.liu@zju.edu.cn>
Cc: stable@vger.kernel.org
Signed-off-by: Bin Liu <b-liu@ti.com>
Link: https://lore.kernel.org/r/20200525025049.3400-7-b-liu@ti.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Dinghao Liu 2020-05-24 21:50:49 -05:00 committed by Greg Kroah-Hartman
parent e8f57f50e3
commit 2d0c87d34d
1 changed files with 5 additions and 5 deletions

View File

@ -168,6 +168,11 @@ static ssize_t musb_test_mode_write(struct file *file,
u8 test;
char buf[24];
memset(buf, 0x00, sizeof(buf));
if (copy_from_user(buf, ubuf, min_t(size_t, sizeof(buf) - 1, count)))
return -EFAULT;
pm_runtime_get_sync(musb->controller);
test = musb_readb(musb->mregs, MUSB_TESTMODE);
if (test) {
@ -176,11 +181,6 @@ static ssize_t musb_test_mode_write(struct file *file,
goto ret;
}
memset(buf, 0x00, sizeof(buf));
if (copy_from_user(buf, ubuf, min_t(size_t, sizeof(buf) - 1, count)))
return -EFAULT;
if (strstarts(buf, "force host full-speed"))
test = MUSB_TEST_FORCE_HOST | MUSB_TEST_FORCE_FS;