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feat: Enhance test_3 to safely read from kernel buffer and return length

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github-actions[bot]
2025-11-16 06:19:28 +00:00
parent 86c2f723f0
commit 8372e9bf1c
1 changed files with 18 additions and 2 deletions
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20
src/features/struct_ops/struct_ops.bpf.c
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@@ -25,9 +25,25 @@ int BPF_PROG(bpf_testmod_test_2, int a, int b)
SEC("struct_ops/test_3")
int BPF_PROG(bpf_testmod_test_3, const char *buf, int len)
{
char read_buf[64] = {0};
int read_len = len < sizeof(read_buf) ? len : sizeof(read_buf) - 1;
bpf_printk("BPF test_3 called with buffer length %d\n", len);
/* Note: Accessing buf pointer requires proper context setup in kernel module */
return 0;
/* Safely read from kernel buffer using bpf_probe_read_kernel */
if (buf && read_len > 0) {
long ret = bpf_probe_read_kernel(read_buf, read_len, buf);
if (ret == 0) {
/* Successfully read buffer - print first few characters */
bpf_printk("Buffer content: '%c%c%c%c'\n",
read_buf[0], read_buf[1], read_buf[2], read_buf[3]);
bpf_printk("Full buffer: %s\n", read_buf);
} else {
bpf_printk("Failed to read buffer, ret=%ld\n", ret);
}
}
return len;
}
/* Define the struct_ops map */