[PATCH] fix use after free in netlink_kernel_create()
From: Akinobu Mita <hidden>
Date: 2006-08-13 10:15:42
Also in:
lkml
This patch invalidates nl_table by setting NULL when netlink initialization failed. Otherwise netlink_kernel_create() would access nl_table which has already been freed. CC: "David S. Miller" <davem@davemloft.net> Signed-off-by: Akinobu Mita <redacted> net/netlink/af_netlink.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) Index: work-failmalloc/net/netlink/af_netlink.c ===================================================================
--- work-failmalloc.orig/net/netlink/af_netlink.c
+++ work-failmalloc/net/netlink/af_netlink.c@@ -1745,11 +1745,8 @@ 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 enomem; if (num_physpages >= (128 * 1024)) max = num_physpages >> (21 - PAGE_SHIFT);
@@ -1769,6 +1766,7 @@ enomem: nl_pid_hash_free(nl_table[i].hash.table, 1 * sizeof(*hash->table)); kfree(nl_table); + nl_table = NULL; goto enomem; } memset(hash->table, 0, 1 * sizeof(*hash->table));
@@ -1786,6 +1784,9 @@ enomem: rtnetlink_init(); out: return err; +enomem: + printk(KERN_CRIT "netlink_init: Cannot allocate nl_table\n"); + return -ENOMEM; } core_initcall(netlink_proto_init);