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| author | Eric Dumazet <edumazet@google.com> | 2013-01-03 22:18:39 +0000 |
|---|---|---|
| committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2013-01-04 20:14:42 +0100 |
| commit | 2727de76041b2064c0b74f00a2a89678fb3efafc (patch) | |
| tree | 57b15dc3cb1e39d7079c60bcf4d76ce34cdb0084 /net | |
| parent | 757ae316fb35811cfd8c67de0e0b8680ec4c1f37 (diff) | |
| download | linux-2727de76041b2064c0b74f00a2a89678fb3efafc.tar.gz linux-2727de76041b2064c0b74f00a2a89678fb3efafc.tar.bz2 linux-2727de76041b2064c0b74f00a2a89678fb3efafc.zip | |
netfilter: xt_recent: avoid high order page allocations
xt_recent can try high order page allocations and this can fail.
iptables: page allocation failure: order:9, mode:0xc0d0
It also wastes about half the allocated space because of kmalloc()
power-of-two roundups and struct recent_table layout.
Use vmalloc() instead to save space and be less prone to allocation
errors when memory is fragmented.
Reported-by: Miroslav Kratochvil <exa.exa@gmail.com>
Reported-by: Dave Jones <davej@redhat.com>
Reported-by: Harald Reindl <h.reindl@thelounge.net>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Diffstat (limited to 'net')
| -rw-r--r-- | net/netfilter/xt_recent.c | 23 |
1 files changed, 18 insertions, 5 deletions
diff --git a/net/netfilter/xt_recent.c b/net/netfilter/xt_recent.c index dab053e2a1a2..978efc9b555a 100644 --- a/net/netfilter/xt_recent.c +++ b/net/netfilter/xt_recent.c @@ -29,6 +29,7 @@ #include <linux/skbuff.h> #include <linux/inet.h> #include <linux/slab.h> +#include <linux/vmalloc.h> #include <net/net_namespace.h> #include <net/netns/generic.h> @@ -310,6 +311,14 @@ out: return ret; } +static void recent_table_free(void *addr) +{ + if (is_vmalloc_addr(addr)) + vfree(addr); + else + kfree(addr); +} + static int recent_mt_check(const struct xt_mtchk_param *par, const struct xt_recent_mtinfo_v1 *info) { @@ -322,6 +331,7 @@ static int recent_mt_check(const struct xt_mtchk_param *par, #endif unsigned int i; int ret = -EINVAL; + size_t sz; if (unlikely(!hash_rnd_inited)) { get_random_bytes(&hash_rnd, sizeof(hash_rnd)); @@ -360,8 +370,11 @@ static int recent_mt_check(const struct xt_mtchk_param *par, goto out; } - t = kzalloc(sizeof(*t) + sizeof(t->iphash[0]) * ip_list_hash_size, - GFP_KERNEL); + sz = sizeof(*t) + sizeof(t->iphash[0]) * ip_list_hash_size; + if (sz <= PAGE_SIZE) + t = kzalloc(sz, GFP_KERNEL); + else + t = vzalloc(sz); if (t == NULL) { ret = -ENOMEM; goto out; @@ -377,14 +390,14 @@ static int recent_mt_check(const struct xt_mtchk_param *par, uid = make_kuid(&init_user_ns, ip_list_uid); gid = make_kgid(&init_user_ns, ip_list_gid); if (!uid_valid(uid) || !gid_valid(gid)) { - kfree(t); + recent_table_free(t); ret = -EINVAL; goto out; } pde = proc_create_data(t->name, ip_list_perms, recent_net->xt_recent, &recent_mt_fops, t); if (pde == NULL) { - kfree(t); + recent_table_free(t); ret = -ENOMEM; goto out; } @@ -435,7 +448,7 @@ static void recent_mt_destroy(const struct xt_mtdtor_param *par) remove_proc_entry(t->name, recent_net->xt_recent); #endif recent_table_flush(t); - kfree(t); + recent_table_free(t); } mutex_unlock(&recent_mutex); } |