ipv4/fib_hash.c: fix NULL dereference

Unless I miss a guaranteed relation between between "f" and
"new_fa->fa_info" this patch is required for fixing a NULL dereference
introduced by commit a6501e080c ("[IPV4]
FIB_HASH: Reduce memory needs and speedup lookups") and spotted by the
Coverity checker.

Eric Dumazet says:

	Hum, you are right, kmem_cache_free() doesnt allow a NULL
	object, like kfree() does.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Adrian Bunk 2008-02-19 16:28:54 -08:00 committed by David S. Miller
parent 15e29b8b05
commit 94cb1503c7

View file

@ -372,7 +372,8 @@ static struct fib_node *fib_find_node(struct fn_zone *fz, __be32 key)
static int fn_hash_insert(struct fib_table *tb, struct fib_config *cfg)
{
struct fn_hash *table = (struct fn_hash *) tb->tb_data;
struct fib_node *new_f, *f;
struct fib_node *new_f = NULL;
struct fib_node *f;
struct fib_alias *fa, *new_fa;
struct fn_zone *fz;
struct fib_info *fi;
@ -496,7 +497,6 @@ static int fn_hash_insert(struct fib_table *tb, struct fib_config *cfg)
err = -ENOBUFS;
new_f = NULL;
if (!f) {
new_f = kmem_cache_zalloc(fn_hash_kmem, GFP_KERNEL);
if (new_f == NULL)
@ -512,7 +512,7 @@ static int fn_hash_insert(struct fib_table *tb, struct fib_config *cfg)
if (new_fa->fa_info != NULL) {
new_fa = kmem_cache_alloc(fn_alias_kmem, GFP_KERNEL);
if (new_fa == NULL)
goto out_free_new_f;
goto out;
}
new_fa->fa_info = fi;
new_fa->fa_tos = tos;
@ -540,9 +540,9 @@ static int fn_hash_insert(struct fib_table *tb, struct fib_config *cfg)
&cfg->fc_nlinfo, 0);
return 0;
out_free_new_f:
kmem_cache_free(fn_hash_kmem, new_f);
out:
if (new_f)
kmem_cache_free(fn_hash_kmem, new_f);
fib_release_info(fi);
return err;
}