[PATCH] [BZ #21812] getifaddrs() Don't return ifa entries with NULL names

[Florian Weimer]

On 06/15/2018 03:29 PM, Daniel Alvarez wrote:
> Due to bug 21812, a lookup operation in map_newlink() turns out
> into an insert because of holes in the interface part of the map.
> This leads to incorrectly set the name of the interface to NULL when
> the interface is not present for the address being processed (most
> likely because the interface was added between the RTM_GETLINK and
> RTM_GETADDR calls to the kernel). When such changes are detected
> by the kernel, it'll mark the dump as "inconsistent" by setting
> NLM_F_DUMP_INTR flag on the next netlink message.
> 
> This patch checks this condition and retries the whole operation.
> Hopes are that next time the interface corresponding to the address
> entry is present in the list and correct name is returned.

I fixed a few cosmetic issues, added a ChangeLog entry, and committed 
this.  Thanks.

I'm working on a self-contained test case, too.

Thanks,
Florian