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linux-usb-gadgets / libusbgx

C library encapsulating the Linux kernel USB gadget configfs userspace API functionality
GNU General Public License v2.0
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Invalid attribute is set in multiple places because of incorrect MACRO #69

Closed wdl-crestron closed 1 year ago

wdl-crestron commented 1 year ago

Because macros are used in multiple places to initialize unnamed unions for example:

#define USBG_F_NET_ETHER_ADDR_TO_ATTR_VAL(WHAT)     \
    USBG_TO_UNION(usbg_f_net_attr_val, dev_addr, WHAT)

....

static inline int usbg_f_net_set_host_addr(usbg_f_net *nf,
                       const struct ether_addr *addr)
{
    return usbg_f_net_set_attr_val(nf, USBG_F_NET_HOST_ADDR,
                       USBG_F_NET_ETHER_ADDR_TO_ATTR_VAL(*addr));
}

this causes invalid attributes to be set, in this case dev_addr field is set to addr which, from function name, should set host_addr. This issue is present in multiple places.

This commit in https://github.com/linux-usb-gadgets/libusbgx/pull/68/commits/8221d20d2a0b2cf6ce180ad97ecb13821a3f30e0 removes problematic macros.

wdl-crestron commented 1 year ago

Incorrect issue report - because of union alignment members are overlapping so all should work. Still somewhat misleading.