diff options
| author | Liping Zhang <zlpnobody@gmail.com> | 2017-01-07 20:51:50 +0800 |
|---|---|---|
| committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2017-01-16 14:23:02 +0100 |
| commit | d21e540b4dd74a26df7a66ebab75c693a4a6a861 (patch) | |
| tree | 64c0279c2c99fad49b78a9c558e6e763b0406035 /net/netfilter/nf_tables_api.c | |
| parent | 6443ebc3fdd6f3c766d9442c18be274b3d736050 (diff) | |
netfilter: nf_tables: fix possible oops when dumping stateful objects
When dumping nft stateful objects, if NFTA_OBJ_TABLE and NFTA_OBJ_TYPE
attributes are not specified either, filter will become NULL, so oops
will happen(actually nft utility will always set NFTA_OBJ_TABLE attr,
so I write a test program to make this happen):
BUG: unable to handle kernel NULL pointer dereference at (null)
IP: nf_tables_dump_obj+0x17c/0x330 [nf_tables]
[...]
Call Trace:
? nf_tables_dump_obj+0x5/0x330 [nf_tables]
? __kmalloc_reserve.isra.35+0x31/0x90
? __alloc_skb+0x5b/0x1e0
netlink_dump+0x124/0x2a0
__netlink_dump_start+0x161/0x190
nf_tables_getobj+0xe8/0x280 [nf_tables]
Fixes: a9fea2a3c3cf ("netfilter: nf_tables: allow to filter stateful object dumps by type")
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Diffstat (limited to 'net/netfilter/nf_tables_api.c')
| -rw-r--r-- | net/netfilter/nf_tables_api.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index 0db5f9782265..091d2dcc63b2 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -4262,10 +4262,11 @@ static int nf_tables_dump_obj(struct sk_buff *skb, struct netlink_callback *cb) if (idx > s_idx) memset(&cb->args[1], 0, sizeof(cb->args) - sizeof(cb->args[0])); - if (filter->table[0] && + if (filter && filter->table[0] && strcmp(filter->table, table->name)) goto cont; - if (filter->type != NFT_OBJECT_UNSPEC && + if (filter && + filter->type != NFT_OBJECT_UNSPEC && obj->type->type != filter->type) goto cont; |