netfilter: flowtable: initialise extack before use

[ Upstream commit e9767137308daf906496613fd879808a07f006a2 ]

Fix missing initialisation of extack in flow offload.

BUG=b/366703777
TEST=presubmit
RELEASE_NOTE=Fixes CVE-2024-45018 in the Linux kernel

cos-patch: security-moderate
Fixes: c29f74e0df7a ("netfilter: nf_flow_table: hardware offload support")
Change-Id: Ifb0301929acde0f9a45180a86227d004e194e069
Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Kernel CVE Triage Automation <cloud-image-kernel-cve-triage-automation@prod.google.com>
Reviewed-on: https://cos-review.googlesource.com/c/third_party/kernel/+/81167
Reviewed-by: Arnav Kansal <rnv@google.com>
Tested-by: Cusky Presubmit Bot <presubmit@cos-infra-prod.iam.gserviceaccount.com>
Reviewed-by: Kevin Berry <kpberry@google.com>

• net/netfilter/nf_flow_table_offload.c[diff]