Draft: CVE-2024-27020: netfilter: nf_tables: Fix potential data-race in __nft_expr_type_get()
requested to merge redhat/red-hat-ci-tools/kernel/bot-branches/centos-stream-9:backport-RHEL-35026-centos-stream-9-main into main
JIRA: https://issues.redhat.com/browse/RHEL-35026
CVE: CVE-2024-27020
netfilter: nf_tables: Fix potential data-race in __nft_expr_type_get()
nft_unregister_expr() can concurrent with __nft_expr_type_get(),
and there is not any protection when iterate over nf_tables_expressions
list in __nft_expr_type_get(). Therefore, there is potential data-race
of nf_tables_expressions list entry.
Use list_for_each_entry_rcu() to iterate over nf_tables_expressions
list in __nft_expr_type_get(), and use rcu_read_lock() in the caller
nft_expr_type_get() to protect the entire type query process.
Fixes: ef1f7df9170d ("netfilter: nf_tables: expression ops overloading")
Signed-off-by: Ziyang Xuan <william.xuanziyang@huawei.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
(cherry picked from commit f969eb84ce482331a991079ab7a5c4dc3b7f89bf)Signed-off-by: cki-backport-bot cki-ci-bot+cki-gitlab-backport-bot@redhat.com