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| author | Dave Jones <davej@codemonkey.org.uk> | 2015-05-19 20:55:17 -0400 |
|---|---|---|
| committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2015-05-20 13:46:49 +0200 |
| commit | 1086bbe97a074844188c6c988fa0b1a98c3ccbb9 (patch) | |
| tree | c4b90cdf9b27072391ec62aa06408e1a57baed1e /net/ipv4 | |
| parent | 3bfe049807c240344b407e3cfb74544927359817 (diff) | |
| download | linux-1086bbe97a074844188c6c988fa0b1a98c3ccbb9.tar.gz linux-1086bbe97a074844188c6c988fa0b1a98c3ccbb9.tar.bz2 linux-1086bbe97a074844188c6c988fa0b1a98c3ccbb9.zip | |
netfilter: ensure number of counters is >0 in do_replace()
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>
Diffstat (limited to 'net/ipv4')
| -rw-r--r-- | net/ipv4/netfilter/arp_tables.c | 6 | ||||
| -rw-r--r-- | net/ipv4/netfilter/ip_tables.c | 6 |
2 files changed, 12 insertions, 0 deletions
diff --git a/net/ipv4/netfilter/arp_tables.c b/net/ipv4/netfilter/arp_tables.c index 13bfe84bf3ca..a61200754f4b 100644 --- a/net/ipv4/netfilter/arp_tables.c +++ b/net/ipv4/netfilter/arp_tables.c @@ -1075,6 +1075,9 @@ static int do_replace(struct net *net, const void __user *user, /* overflow check */ if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters)) return -ENOMEM; + if (tmp.num_counters == 0) + return -EINVAL; + tmp.name[sizeof(tmp.name)-1] = 0; newinfo = xt_alloc_table_info(tmp.size); @@ -1499,6 +1502,9 @@ static int compat_do_replace(struct net *net, void __user *user, return -ENOMEM; if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters)) return -ENOMEM; + if (tmp.num_counters == 0) + return -EINVAL; + tmp.name[sizeof(tmp.name)-1] = 0; newinfo = xt_alloc_table_info(tmp.size); diff --git a/net/ipv4/netfilter/ip_tables.c b/net/ipv4/netfilter/ip_tables.c index c69db7fa25ee..2d0e265fef6e 100644 --- a/net/ipv4/netfilter/ip_tables.c +++ b/net/ipv4/netfilter/ip_tables.c @@ -1262,6 +1262,9 @@ do_replace(struct net *net, const void __user *user, unsigned int len) /* overflow check */ if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters)) return -ENOMEM; + if (tmp.num_counters == 0) + return -EINVAL; + tmp.name[sizeof(tmp.name)-1] = 0; newinfo = xt_alloc_table_info(tmp.size); @@ -1809,6 +1812,9 @@ compat_do_replace(struct net *net, void __user *user, unsigned int len) return -ENOMEM; if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters)) return -ENOMEM; + if (tmp.num_counters == 0) + return -EINVAL; + tmp.name[sizeof(tmp.name)-1] = 0; newinfo = xt_alloc_table_info(tmp.size); |