Commit 9f12fbe6 authored by Zi Shen Lim's avatar Zi Shen Lim Committed by David S. Miller
Browse files

net: filter: move load_pointer() into filter.h 



load_pointer() is already a static inline function.
Let's move it into filter.h so BPF JIT implementations can reuse this
function.

Since we're exporting this function, let's also rename it to
bpf_load_pointer() for clarity.

Signed-off-by: default avatarZi Shen Lim <zlim.lnx@gmail.com>
Reviewed-by: default avatarDaniel Borkmann <dborkman@redhat.com>
Acked-by: default avatarAlexei Starovoitov <ast@plumgrid.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 3d5baba0

include/linux/filter.h

+13 −0
Original line number Diff line number Diff line
@@ -6,6 +6,7 @@ 


#include <linux/atomic.h>

#include <linux/compat.h>

#include <linux/skbuff.h>

#include <linux/workqueue.h>

#include <uapi/linux/filter.h>
@@ -406,6 +407,18 @@ static inline u16 bpf_anc_helper(const struct sock_filter *ftest) 
	}

}



void *bpf_internal_load_pointer_neg_helper(const struct sk_buff *skb,

					   int k, unsigned int size);



static inline void *bpf_load_pointer(const struct sk_buff *skb, int k,

				     unsigned int size, void *buffer)

{

	if (k >= 0)

		return skb_header_pointer(skb, k, size, buffer);



	return bpf_internal_load_pointer_neg_helper(skb, k, size);

}



#ifdef CONFIG_BPF_JIT

#include <stdarg.h>

#include <linux/linkage.h>

net/core/filter.c

+3 −12
Original line number Diff line number Diff line
@@ -84,15 +84,6 @@ void *bpf_internal_load_pointer_neg_helper(const struct sk_buff *skb, int k, uns 
	return NULL;

}



static inline void *load_pointer(const struct sk_buff *skb, int k,

				 unsigned int size, void *buffer)

{

	if (k >= 0)

		return skb_header_pointer(skb, k, size, buffer);



	return bpf_internal_load_pointer_neg_helper(skb, k, size);

}



/**

 *	sk_filter - run a packet through a socket filter

 *	@sk: sock associated with &sk_buff
@@ -537,7 +528,7 @@ load_word: 
		 *   BPF_R0 - 8/16/32-bit skb data converted to cpu endianness

		 */



		ptr = load_pointer((struct sk_buff *) (unsigned long) CTX, off, 4, &tmp);

		ptr = bpf_load_pointer((struct sk_buff *) (unsigned long) CTX, off, 4, &tmp);

		if (likely(ptr != NULL)) {

			BPF_R0 = get_unaligned_be32(ptr);

			CONT;
@@ -547,7 +538,7 @@ load_word: 
	LD_ABS_H: /* BPF_R0 = ntohs(*(u16 *) (skb->data + imm32)) */

		off = IMM;

load_half:

		ptr = load_pointer((struct sk_buff *) (unsigned long) CTX, off, 2, &tmp);

		ptr = bpf_load_pointer((struct sk_buff *) (unsigned long) CTX, off, 2, &tmp);

		if (likely(ptr != NULL)) {

			BPF_R0 = get_unaligned_be16(ptr);

			CONT;
@@ -557,7 +548,7 @@ load_half: 
	LD_ABS_B: /* BPF_R0 = *(u8 *) (skb->data + imm32) */

		off = IMM;

load_byte:

		ptr = load_pointer((struct sk_buff *) (unsigned long) CTX, off, 1, &tmp);

		ptr = bpf_load_pointer((struct sk_buff *) (unsigned long) CTX, off, 1, &tmp);

		if (likely(ptr != NULL)) {

			BPF_R0 = *(u8 *)ptr;

			CONT;

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