Bug #1631: kernel panic in tcp_input_data
1631's fix missed the case of data on the handshake's ACK
|Assignee:||Dan McDonald||% Done:|
Consider this exchange:
a->b SYN b->a SYN/ACK a->b ACK+data(PSH)
this is legal, and the data should be delivered, but after 1631 the data will drop. In DEBUG kernels, it will cause an assertion failure in tcp_dummy_recv().
What happens is that with 1631, "sockupcalls" is initialized early on, which is good when conn_upcalls is NULL (and can be replaced), but upon receipt of the third ACK, conn_upcalls is upgraded from NULL to non-NULL. If there is data on that ACK, "sockupcalls" is still NULL in this case, and the data is sent to tcp_dummy_recv.
#1 Updated by Gordon Ross about 4 years ago
- Status changed from New to Resolved
changeset: 13521:901a793ed0dd user: Dan McDonald <email@example.com> date: Mon Nov 14 19:23:57 2011 -0500 description: 1775 1631's fix missed the case of data on the handshake's ACK Reviewed by: Michael Speer <firstname.lastname@example.org> Reviewed by: Garrett D'Amore <Garrett.DAmore@nexenta.com> Reviewed by: Gordon Ross <email@example.com> Approved by: Gordon Ross <firstname.lastname@example.org>
Also available in: Atom