[PATCH] netfilter: ipset: fix ip_set_list allocation failure

From: Andrey Ryabinin
Date: Wed Aug 01 2018 - 12:46:46 EST


ip_set_create() and ip_set_net_init() attempt to allocate physically
contiguous memory for ip_set_list. If memory is fragmented, the
allocations could easily fail:

vzctl: page allocation failure: order:7, mode:0xc0d0

Call Trace:
dump_stack+0x19/0x1b
warn_alloc_failed+0x110/0x180
__alloc_pages_nodemask+0x7bf/0xc60
alloc_pages_current+0x98/0x110
kmalloc_order+0x18/0x40
kmalloc_order_trace+0x26/0xa0
__kmalloc+0x279/0x290
ip_set_net_init+0x4b/0x90 [ip_set]
ops_init+0x3b/0xb0
setup_net+0xbb/0x170
copy_net_ns+0xf1/0x1c0
create_new_namespaces+0xf9/0x180
copy_namespaces+0x8e/0xd0
copy_process+0xb61/0x1a00
do_fork+0x91/0x320

Use kvcalloc() to fallback to 0-order allocations if high order
page isn't available.

Signed-off-by: Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx>
---
net/netfilter/ipset/ip_set_core.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/net/netfilter/ipset/ip_set_core.c b/net/netfilter/ipset/ip_set_core.c
index bc4bd247bb7d..96dd57c48b1c 100644
--- a/net/netfilter/ipset/ip_set_core.c
+++ b/net/netfilter/ipset/ip_set_core.c
@@ -961,7 +961,7 @@ static int ip_set_create(struct net *net, struct sock *ctnl,
/* Wraparound */
goto cleanup;

- list = kcalloc(i, sizeof(struct ip_set *), GFP_KERNEL);
+ list = kvcalloc(i, sizeof(struct ip_set *), GFP_KERNEL);
if (!list)
goto cleanup;
/* nfnl mutex is held, both lists are valid */
@@ -973,7 +973,7 @@ static int ip_set_create(struct net *net, struct sock *ctnl,
/* Use new list */
index = inst->ip_set_max;
inst->ip_set_max = i;
- kfree(tmp);
+ kvfree(tmp);
ret = 0;
} else if (ret) {
goto cleanup;
@@ -2059,7 +2059,7 @@ ip_set_net_init(struct net *net)
if (inst->ip_set_max >= IPSET_INVALID_ID)
inst->ip_set_max = IPSET_INVALID_ID - 1;

- list = kcalloc(inst->ip_set_max, sizeof(struct ip_set *), GFP_KERNEL);
+ list = kvcalloc(inst->ip_set_max, sizeof(struct ip_set *), GFP_KERNEL);
if (!list)
return -ENOMEM;
inst->is_deleted = false;
@@ -2087,7 +2087,7 @@ ip_set_net_exit(struct net *net)
}
}
nfnl_unlock(NFNL_SUBSYS_IPSET);
- kfree(rcu_dereference_protected(inst->ip_set_list, 1));
+ kvfree(rcu_dereference_protected(inst->ip_set_list, 1));
}

static struct pernet_operations ip_set_net_ops = {
--
2.16.4