netfilter: nf_tables: fix oops during rule dump
We can oops in nf_tables_fill_rule_info().
Its not possible to fetch previous element in rcu-protected lists
when deletions are not prevented somehow: list_del_rcu poisons
the ->prev pointer value.
Before rcu-conversion this was safe as dump operations did hold
nfnetlink mutex.
Pass previous rule as argument, obtained by keeping a pointer to
the previous rule during traversal.
Fixes: d9adf22a291883 ("netfilter: nf_tables: use call_rcu in netlink dumps")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
1 file changed