call panic if nl_table allocation fails

From: Akinobu Mita
Date: Wed Aug 23 2006 - 07:35:03 EST


This patch makes crash happen if initialization of nl_table fails
in initcalls. It is better than getting use after free crash later.

Cc: Patrick McHardy <kaber@xxxxxxxxx>
Cc: David Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Akinobu Mita <mita@xxxxxxxxxxxxxxxx>

Index: work-failmalloc/net/netlink/af_netlink.c
===================================================================
--- work-failmalloc.orig/net/netlink/af_netlink.c
+++ work-failmalloc/net/netlink/af_netlink.c
@@ -1273,8 +1273,7 @@ netlink_kernel_create(int unit, unsigned
struct netlink_sock *nlk;
unsigned long *listeners = NULL;

- if (!nl_table)
- return NULL;
+ BUG_ON(!nl_table);

if (unit<0 || unit>=MAX_LINKS)
return NULL;
@@ -1745,11 +1744,8 @@ static int __init netlink_proto_init(voi
netlink_skb_parms_too_large();

nl_table = kcalloc(MAX_LINKS, sizeof(*nl_table), GFP_KERNEL);
- if (!nl_table) {
-enomem:
- printk(KERN_CRIT "netlink_init: Cannot allocate nl_table\n");
- return -ENOMEM;
- }
+ if (!nl_table)
+ goto panic;

if (num_physpages >= (128 * 1024))
max = num_physpages >> (21 - PAGE_SHIFT);
@@ -1769,7 +1765,7 @@ enomem:
nl_pid_hash_free(nl_table[i].hash.table,
1 * sizeof(*hash->table));
kfree(nl_table);
- goto enomem;
+ goto panic;
}
memset(hash->table, 0, 1 * sizeof(*hash->table));
hash->max_shift = order;
@@ -1786,6 +1782,8 @@ enomem:
rtnetlink_init();
out:
return err;
+panic:
+ panic("netlink_init: Cannot allocate nl_table\n");
}

core_initcall(netlink_proto_init);
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/