ipv6: add defensive check for CHECKSUM_PARTIAL skbs in ip_fragment
ipv6: add defensive check for CHECKSUM_PARTIAL skbs in ip_fragment

CHECKSUM_PARTIAL skbs should never arrive in ip_fragment. If we get one
of those warn about them once and handle them gracefully by recalculating
the checksum.

Fixes: commit 32dce968dd987 ("ipv6: Allow for partial checksums on non-ufo packets")
See-also: commit 72e843bb09d45 ("ipv6: ip6_fragment() should check CHECKSUM_PARTIAL")
Cc: Eric Dumazet <312c7d941f03386814be517ffdb3e0eb6624e275@google.com>
Cc: Vlad Yasevich <df4bbba3da7ae0371dc686d07d0ceb66ffa78730@gmail.com>
Cc: Benjamin Coddington <8448cf767486b00c07603be762726b9248f4b321@redhat.com>
Cc: Tom Herbert <96835dd8bfa718bd6447ccc87af89ae1675daeca@herbertland.com>
Signed-off-by: Hannes Frederic Sowa <331be22c6b63ca3e0a03d408c2d906b1b02cd5f2@stressinduktion.org>
Signed-off-by: David S. Miller <fe08d3c717adf2ae63592e4c9aec6e3e404d8e3e@davemloft.net>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs