net: asix: add proper error handling of usb read errors

Vulnerability Description

In the Linux kernel, the following vulnerability has been resolved: net: asix: add proper error handling of usb read errors Syzbot once again hit uninit value in asix driver. The problem still the same -- asix_read_cmd() reads less bytes, than was requested by caller. Since all read requests are performed via asix_read_cmd() let's catch usb related error there and add __must_check notation to be sure all callers actually check return value. So, this patch adds sanity check inside asix_read_cmd(), that simply checks if bytes read are not less, than was requested and adds missing error handling of asix_read_cmd() all across the driver code.

References

• https://git.kernel.org/stable/c/b96a7265f763b37ff3138b9ca8122a950f13b00e
• https://git.kernel.org/stable/c/9ea8d2fca8fea3b17005b4dc02f8ef15f7a2fb97
• https://git.kernel.org/stable/c/662ff765470ad0d11a1153d6d8e99d69a98e60b4
• https://git.kernel.org/stable/c/920a9fa27e7805499cfe78491b36fed2322c02ec