title: tunnels: fix out of bounds access when building IPv6 PMTU error
description: In the Linux kernel, the following vulnerability has been resolved:
tunnels: fix out of bounds access when building IPv6 PMTU error
If the ICMPv6 error is built from a non-linear skb we get the following
splat,
BUG: KASAN: slab-out-of-bounds in do_csum+0x220/0x240
Read of size 4 at addr ffff88811d402c80 by task netperf/820
CPU: 0 PID: 820 Comm: netperf Not tainted 6.8.0-rc1+ #543
...
kasan_report+0xd8/0x110
do_csum+0x220/0x240
csum_partial+0xc/0x20
skb_tunnel_check_pmtu+0xeb9/0x3280
vxlan_xmit_one+0x14c2/0x4080
vxlan_xmit+0xf61/0x5c00
dev_hard_start_xmit+0xfb/0x510
__dev_queue_xmit+0x7cd/0x32a0
br_dev_queue_push_xmit+0x39d/0x6a0
Use skb_checksum instead of csum_partial who cannot deal with non-linear
SKBs.
affected:
{
product: Linux
vendor: Linux
defaultStatus: unaffected
repo: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
versions:
version: 4cb47a8644cc, lessThan: e77bf828f1ca, status: affected, versionType: git
version: 4cb47a8644cc, lessThan: d964dd1bc145, status: affected, versionType: git
version: 4cb47a8644cc, lessThan: e37cde7a5716, status: affected, versionType: git
version: 4cb47a8644cc, lessThan: 510c869ffa40, status: affected, versionType: git
version: 4cb47a8644cc, lessThan: 7dc9feb8b170, status: affected, versionType: git
version: 4cb47a8644cc, lessThan: d75abeec401f, status: affected, versionType: git
}
{
product: Linux
vendor: Linux
defaultStatus: affected
repo: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
versions:
version: 5.9, status: affected
version: 0, lessThan: 5.9, status: unaffected, versionType: custom
version: 5.10.210, lessThanOrEqual: 5.10.*, status: unaffected, versionType: custom
version: 5.15.149, lessThanOrEqual: 5.15.*, status: unaffected, versionType: custom
version: 6.1.78, lessThanOrEqual: 6.1.*, status: unaffected, versionType: custom
version: 6.6.17, lessThanOrEqual: 6.6.*, status: unaffected, versionType: custom
version: 6.7.5, lessThanOrEqual: 6.7.*, status: unaffected, versionType: custom
version: 6.8, lessThanOrEqual: *, status: unaffected, versionType: original_commit_for_fix
}
