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#include <linux/bpf.h>
#include <bpf/bpf_helpers.h>
#include <bpf/bpf_endian.h>
SEC("sk_skb1")
int bpf_prog1(struct __sk_buff *skb)
{
void *data_end = (void *)(long) skb->data_end;
void *data = (void *)(long) skb->data;
__u8 *d = data;
int err;
if (data + 10 > data_end) {
err = bpf_skb_pull_data(skb, 10);
if (err)
return SK_DROP;
data_end = (void *)(long)skb->data_end;
data = (void *)(long)skb->data;
if (data + 10 > data_end)
return SK_DROP;
}
/* This write/read is a bit pointless but tests the verifier and
* strparser handler for read/write pkt data and access into sk
* fields.
*/
d = data;
d[7] = 1;
return skb->len;
}
char _license[] SEC("license") = "GPL";
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