Dave Jones <davej@xxxxxxxxxxxxxxxxx> wrote: > 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. > > Signed-off-by: Dave Jones <davej@xxxxxxxxxxxxxxxxx> > > diff --git a/net/ipv4/netfilter/ip_tables.c b/net/ipv4/netfilter/ip_tables.c > index c69db7fa25ee..12a33d178614 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; > + Good catch. Due to iptables wonderful copy-paste programming model, this also needs fixing in compat_do_replace, ip6tables, arbtables and ebtables (8 different places, ick). -- To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
