diff options
| author | Dave Jones <davej@codemonkey.org.uk> | 2015-05-19 20:55:17 -0400 |
|---|---|---|
| committer | Ben Hutchings <ben@decadent.org.uk> | 2016-08-22 22:38:31 +0100 |
| commit | 30efc09c28d78030584885a691f6bee8c9102d33 (patch) | |
| tree | eda9887db310e4fd18b0a0de08d183d8c147d6cd /net/bridge | |
| parent | 019475d64600fad9051f7197aa9c5feed93243cc (diff) | |
netfilter: ensure number of counters is >0 in do_replace()
commit 1086bbe97a074844188c6c988fa0b1a98c3ccbb9 upstream.
After improving setsockopt() coverage in trinity, I started triggering
vmalloc failures pretty reliably from this code path:
warn_alloc_failed+0xe9/0x140
__vmalloc_node_range+0x1be/0x270
vzalloc+0x4b/0x50
__do_replace+0x52/0x260 [ip_tables]
do_ipt_set_ctl+0x15d/0x1d0 [ip_tables]
nf_setsockopt+0x65/0x90
ip_setsockopt+0x61/0xa0
raw_setsockopt+0x16/0x60
sock_common_setsockopt+0x14/0x20
SyS_setsockopt+0x71/0xd0
It turns out we don't validate that the num_counters field in the
struct we pass in from userspace is initialized.
The same problem also exists in ebtables, arptables, ipv6, and the
compat variants.
Signed-off-by: Dave Jones <davej@codemonkey.org.uk>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Diffstat (limited to 'net/bridge')
| -rw-r--r-- | net/bridge/netfilter/ebtables.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/net/bridge/netfilter/ebtables.c b/net/bridge/netfilter/ebtables.c index 1059ed3bc255..42ee65e1bc7f 100644 --- a/net/bridge/netfilter/ebtables.c +++ b/net/bridge/netfilter/ebtables.c @@ -1105,6 +1105,8 @@ static int do_replace(struct net *net, const void __user *user, return -ENOMEM; if (tmp.num_counters >= INT_MAX / sizeof(struct ebt_counter)) return -ENOMEM; + if (tmp.num_counters == 0) + return -EINVAL; tmp.name[sizeof(tmp.name) - 1] = 0; @@ -2150,6 +2152,8 @@ static int compat_copy_ebt_replace_from_user(struct ebt_replace *repl, return -ENOMEM; if (tmp.num_counters >= INT_MAX / sizeof(struct ebt_counter)) return -ENOMEM; + if (tmp.num_counters == 0) + return -EINVAL; memcpy(repl, &tmp, offsetof(struct ebt_replace, hook_entry)); |