Page MenuHomeFreeBSD

netinet*: replace IP6_EXTHDR_GET()

Authored by bz on Nov 12 2019, 6:05 PM.



In a few places we have IP6_EXTHDR_GET() left in upper layer protocols.
The IP6_EXTHDR_GET() macro might perform an m_pulldown() in case the data
fragment is not contiguous.

Convert these last remaining instances into m_pullup()s instead.
In CARP, for example, we will a few lines later call m_pullup() anyway,
the IPsec code coming from OpenBSD would otherwise have done the m_pullup()
and are copying the data a bit later anyway, so pulling it in seems no
better or worse.

Note: this leaves very few m_pulldown() cases behind in the tree and we
might want to consider removing them as well to make mbuf management
easier again on a path to variable size mbufs, especially given
m_pulldown() still has an issue not re-checking M_WRITEABLE().

Diff Detail

rS FreeBSD src repository
Automatic diff as part of commit; lint not applicable.
Automatic diff as part of commit; unit tests not applicable.

Event Timeline

bz created this revision.Nov 12 2019, 6:05 PM
gallatin accepted this revision.Nov 15 2019, 2:37 PM
This revision is now accepted and ready to land.Nov 15 2019, 2:37 PM
This revision was automatically updated to reflect the committed changes.