skbuff: fix incorrect msg_zerocopy copy notifications

msg_zerocopy signals if a send operation required copying with a flag
in serr->ee.ee_code.

This field can be incorrect as of the below commit, as a result of
both structs uarg and serr pointing into the same skb->cb[].

uarg->zerocopy must be read before skb->cb[] is reinitialized to hold
serr. Similar to other fields len, hi and lo, use a local variable to
temporarily hold the value.

This was not a problem before, when the value was passed as a function
argument.

Fixes: 75518851a2a0 ("skbuff: Push status and refcounts into sock_zerocopy_callback")
Reported-by: Talal Ahmad <[email protected]>
Signed-off-by: Willem de Bruijn <[email protected]>
Acked-by: Soheil Hassas Yeganeh <[email protected]>
Reviewed-by: Eric Dumazet <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

0 files changed, 0 insertions, 0 deletions