From: "Ilpo Järvinen" <redacted>
Date: Tue, 25 Nov 2008 22:08:06 +0200 (EET)

Since pskb_expand_head creates copy of the shared area we
cannot keep any frag ptr past de-cloning. This fixes the
tcpdump recvfrom -EFAULT problem.

Signed-off-by: Ilpo Järvinen <redacted>

Good catch.

I think everyone mucking around with these sorts of things
has made this error at least once or twice :)