Use bpf_probe_read_kernel() instead of bpf_probe_read(), which is not
defined on all architectures.
While at it, improve the error handling: do not hide the verifier log,
and check the return values of bpf_probe_read_kernel() and
bpf_copy_from_user().
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Link: https://lore.kernel.org/r/20230128000650.1516334-10-iii@linux.ibm.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
static int libbpf_print_cb(enum libbpf_print_level level, const char *fmt,
va_list args)
{
+ if (level == LIBBPF_WARN)
+ vprintf(fmt, args);
+
if (strcmp(fmt, "libbpf: extern (func ksym) '%s': not found in kernel or module BTFs\n"))
return 0;
if (!data_val)
return 0;
- bpf_probe_read(&value, sizeof(value), &attr->value);
-
- bpf_copy_from_user(data_val, sizeof(struct data),
- (void *)(unsigned long)value);
+ ret = bpf_probe_read_kernel(&value, sizeof(value), &attr->value);
+ if (ret)
+ return ret;
+
+ ret = bpf_copy_from_user(data_val, sizeof(struct data),
+ (void *)(unsigned long)value);
+ if (ret)
+ return ret;
if (data_val->data_len > sizeof(data_val->data))
return -EINVAL;