Bug #1775
Bug #1631: kernel panic in tcp_input_data
1631's fix missed the case of data on the handshake's ACK
| Status: | Resolved | Start date: | 2011-11-14 | ||
|---|---|---|---|---|---|
| Priority: | Urgent | Due date: | |||
| Assignee: |  Dan McDonald | % Done: | 80% | ||
| Category: | kernel | ||||
| Target version: | - | ||||
| Difficulty: | Medium | Tags: | diagnosed |
Description
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.
History
#1
Updated by Gordon Ross over 6 years ago
- Status changed from New to Resolved
changeset: 13521:901a793ed0dd
user: Dan McDonald <danmcd@nexenta.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 <michael.speer@pluribusnetworks.com>
Reviewed by: Garrett D'Amore <Garrett.DAmore@nexenta.com>
Reviewed by: Gordon Ross <gwr@nexenta.com>
Approved by: Gordon Ross <gwr@nexenta.com>
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