kernel/linux.git/include/linux/netfilter.h, branch v5.4.146

netfilter: clear skb->next in NF_HOOK_LIST()

2020-12-02T07:49:44+00:00

NF_HOOK_LIST() uses list_del() to remove skb from the linked list, however, it is not sufficient as skb->next still points to other skb. We should just call skb_list_del_init() to clear skb->next, like the rest places which using skb list. This has been fixed in upstream by commit ca58fbe06c54 ("netfilter: add and use nf_hook_slow_list()"). Fixes: 9f17dbf04ddf ("netfilter: fix use-after-free in NF_HOOK_LIST") Reported-by: liuzx@knownsec.com Tested-by: liuzx@knownsec.com Cc: Florian Westphal Cc: Edward Cree Cc: stable@vger.kernel.org # between 4.19 and 5.4 Signed-off-by: Cong Wang Signed-off-by: Greg Kroah-Hartman

netfilter: remove CONFIG_NETFILTER checks from headers.

2019-09-13T10:47:36+00:00

`struct nf_hook_ops`, `struct nf_hook_state` and the `nf_hookfn` function typedef appear in function and struct declarations and definitions in a number of netfilter headers. The structs and typedef themselves are defined by linux/netfilter.h but only when CONFIG_NETFILTER is enabled. Define them unconditionally and add forward declarations in order to remove CONFIG_NETFILTER conditionals from the other headers. Signed-off-by: Jeremy Sowden Signed-off-by: Pablo Neira Ayuso

netfilter: replace defined(CONFIG...) || defined(CONFIG...MODULE) with IS_ENABLED(CONFIG...).

2019-09-13T10:47:09+00:00

A few headers contain instances of: #if defined(CONFIG_XXX) or defined(CONFIG_XXX_MODULE) Replace them with: #if IS_ENABLED(CONFIG_XXX) Signed-off-by: Jeremy Sowden Signed-off-by: Pablo Neira Ayuso

netfilter: replace skb_make_writable with skb_ensure_writable

2019-05-31T16:02:48+00:00

This converts all remaining users and then removes skb_make_writable. Suggested-by: Daniel Borkmann Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso

netfilter: slightly optimize nf_inet_addr_mask

2019-05-05T23:18:58+00:00

using 64bit computation to slightly optimize nf_inet_addr_mask Signed-off-by: Li RongQing Signed-off-by: Pablo Neira Ayuso

netfilter: replace NF_NAT_NEEDED with IS_ENABLED(CONFIG_NF_NAT)

2019-04-08T21:02:52+00:00

NF_NAT_NEEDED is true whenever nat support for either ipv4 or ipv6 is enabled. Now that the af-specific nat configuration switches have been removed, IS_ENABLED(CONFIG_NF_NAT) has the same effect. Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso

netfilter: optimize nf_inet_addr_cmp

2019-04-08T20:58:16+00:00

optimize nf_inet_addr_cmp by 64bit xor computation similar to ipv6_addr_equal() Signed-off-by: Yuan Linsi Signed-off-by: Li RongQing Signed-off-by: Pablo Neira Ayuso

jump_label: move 'asm goto' support test to Kconfig

2019-01-06T00:46:51+00:00

Currently, CONFIG_JUMP_LABEL just means "I _want_ to use jump label". The jump label is controlled by HAVE_JUMP_LABEL, which is defined like this: #if defined(CC_HAVE_ASM_GOTO) && defined(CONFIG_JUMP_LABEL) # define HAVE_JUMP_LABEL #endif We can improve this by testing 'asm goto' support in Kconfig, then make JUMP_LABEL depend on CC_HAS_ASM_GOTO. Ugly #ifdef HAVE_JUMP_LABEL will go away, and CONFIG_JUMP_LABEL will match to the real kernel capability. Signed-off-by: Masahiro Yamada Acked-by: Michael Ellerman (powerpc) Tested-by: Sedat Dilek

netfilter: avoid erronous array bounds warning

2018-09-28T12:47:40+00:00

Unfortunately some versions of gcc emit following warning: $ make net/xfrm/xfrm_output.o linux/compiler.h:252:20: warning: array subscript is above array bounds [-Warray-bounds] hook_head = rcu_dereference(net->nf.hooks_arp[hook]); ^~~~~~~~~~~~~~~~~~~~~ xfrm_output_resume passes skb_dst(skb)->ops->family as its 'pf' arg so compiler can't know that we'll never access hooks_arp[]. (NFPROTO_IPV4 or NFPROTO_IPV6 are only possible cases). Avoid this by adding an explicit WARN_ON_ONCE() check. This patch has no effect if the family is a compile-time constant as gcc will remove the switch() construct entirely. Reported-by: David Ahern Signed-off-by: Florian Westphal Reviewed-by: David Ahern Signed-off-by: Pablo Neira Ayuso

netfilter: Add nf_ct_get_tuple_skb global lookup function

2018-07-11T03:06:34+00:00

This adds a global netfilter function to extract a conntrack tuple from an skb. The function uses a new function added to nf_ct_hook, which will try to get the tuple from skb->_nfct, and do a full lookup if that fails. This makes it possible to use the lookup function before the skb has passed through the conntrack init hooks (e.g., in an ingress qdisc). The tuple is copied to the caller to avoid issues with reference counting. The function returns false if conntrack is not loaded, allowing it to be used without incurring a module dependency on conntrack. This is used by the NAT mode in sch_cake. Cc: netfilter-devel@vger.kernel.org Signed-off-by: Toke Høiland-Jørgensen Signed-off-by: David S. Miller