Commit 1e2bd517c108816220f262d7954b697af03b5f9c ("udp6: Fix udp
fragmentation for tunnel traffic.") changed the calculation if
there is enough space to include a fragment header in the skb from a
skb->mac_header dervived one to skb_headroom. Because we already peeled
off the skb to transport_header this is wrong.
This fixes a panic Saran Neti reported. He used the tbf scheduler which
skb_gso_segments the skb. The offsets get negative and we panic in memcpy
because the skb was erroneously not expanded at the head.
Red Hat would like to thank Saran Neti of TELUS Security Labs for reporting this issue.
Created kernel tracking bugs for this issue:
Affects: fedora-all [bug 1030017]
This issue did not affect the Linux kernel packages as shipped with Red Hat Enterprise Linux 5, 6 and Red Hat Enterprise MRG 2.
kernel-3.11.9-200.fc19 has been pushed to the Fedora 19 stable repository. If problems still persist, please make note of it in this bug report.
kernel-3.11.9-300.fc20 has been pushed to the Fedora 20 stable repository. If problems still persist, please make note of it in this bug report.
kernel-3.11.9-100.fc18 has been pushed to the Fedora 18 stable repository. If problems still persist, please make note of it in this bug report.