diff options
| author | Pavel Tikhomirov <ptikhomirov@virtuozzo.com> | 2023-02-13 12:25:05 +0800 |
|---|---|---|
| committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2023-02-22 10:11:27 +0100 |
| commit | 0af8c09c896810879387decfba8c942994bb61f5 (patch) | |
| tree | 9a032dc1502e0a987765e3584cc17b174ece0673 /net/ipv4 | |
| parent | fdf6491193e411087ae77bcbc6468e3e1cff99ed (diff) | |
netfilter: x_tables: fix percpu counter block leak on error path when creating new netns
Here is the stack where we allocate percpu counter block:
+-< __alloc_percpu
+-< xt_percpu_counter_alloc
+-< find_check_entry # {arp,ip,ip6}_tables.c
+-< translate_table
And it can be leaked on this code path:
+-> ip6t_register_table
+-> translate_table # allocates percpu counter block
+-> xt_register_table # fails
there is no freeing of the counter block on xt_register_table fail.
Note: xt_percpu_counter_free should be called to free it like we do in
do_replace through cleanup_entry helper (or in __ip6t_unregister_table).
Probability of hitting this error path is low AFAICS (xt_register_table
can only return ENOMEM here, as it is not replacing anything, as we are
creating new netns, and it is hard to imagine that all previous
allocations succeeded and after that one in xt_register_table failed).
But it's worth fixing even the rare leak.
Fixes: 71ae0dff02d7 ("netfilter: xtables: use percpu rule counters")
Signed-off-by: Pavel Tikhomirov <ptikhomirov@virtuozzo.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Diffstat (limited to 'net/ipv4')
| -rw-r--r-- | net/ipv4/netfilter/arp_tables.c | 4 | ||||
| -rw-r--r-- | net/ipv4/netfilter/ip_tables.c | 4 |
2 files changed, 8 insertions, 0 deletions
diff --git a/net/ipv4/netfilter/arp_tables.c b/net/ipv4/netfilter/arp_tables.c index ffc0cab7cf18..2407066b0fec 100644 --- a/net/ipv4/netfilter/arp_tables.c +++ b/net/ipv4/netfilter/arp_tables.c @@ -1525,6 +1525,10 @@ int arpt_register_table(struct net *net, new_table = xt_register_table(net, table, &bootstrap, newinfo); if (IS_ERR(new_table)) { + struct arpt_entry *iter; + + xt_entry_foreach(iter, loc_cpu_entry, newinfo->size) + cleanup_entry(iter, net); xt_free_table_info(newinfo); return PTR_ERR(new_table); } diff --git a/net/ipv4/netfilter/ip_tables.c b/net/ipv4/netfilter/ip_tables.c index aae5fd51dfd7..da5998011ab9 100644 --- a/net/ipv4/netfilter/ip_tables.c +++ b/net/ipv4/netfilter/ip_tables.c @@ -1741,6 +1741,10 @@ int ipt_register_table(struct net *net, const struct xt_table *table, new_table = xt_register_table(net, table, &bootstrap, newinfo); if (IS_ERR(new_table)) { + struct ipt_entry *iter; + + xt_entry_foreach(iter, loc_cpu_entry, newinfo->size) + cleanup_entry(iter, net); xt_free_table_info(newinfo); return PTR_ERR(new_table); } |