On Thu, Apr 17, 2025 at 03:00:18PM -0700, Zaid Alali wrote:
> + if (is_V2) {
> + int count = 0, bytes_read, pos = 0, nr_parsed = 0, str_len;
> + unsigned int comp, synd;
I've been staring at the ACPI spec to try and figure out how many bits
are needed for comp and sync. The example in section 18.6.7 "Error
Injection Version 2 Operation" has this in step 6:
Component Syndrome Array [0] = { 00000000000000000000000000000004 , 000000000000000000000000A5A5A5A5 }
Which really looks like 128-bit values!
So are "unsigned int" adequate? Even "u64" looks like it would fall short.
> + struct syndrome_array *component_arr;
> +
> + component_arr = v5param->einjv2_struct.component_arr;
> + str_len = strlen(user_input);
> +
> + while ((nr_parsed = sscanf(user_input + pos, "%x %x\n%n", &comp,
Parsing user input with sscanf() is a bit fragile. Take a look at
rdtgroup_schemata_write() which uses:
while ((tok = strsep(&buf, "\n")) != NULL) {
to split input into lines, and then strim() and strsep() to break
up items within a line.
> + &synd, &bytes_read))) {
> + pos += bytes_read;
> +
> + if (nr_parsed != 2) {
> + kfree(v5param);
> + goto err_out;
> + }
> + if (count >= nr_components) {
> + kfree(v5param);
> + goto err_out;
> + }
> +
> + switch (type) {
> + case EINJV2_PROCESSOR_ERROR:
> + component_arr[count].comp_id.acpi_id = comp;
> + component_arr[count].comp_synd.proc_synd = synd;
> + break;
> + case EINJV2_MEMORY_ERROR:
> + component_arr[count].comp_id.device_id = comp;
> + component_arr[count].comp_synd.mem_synd = synd;
> + break;
> + case EINJV2_PCIE_ERROR:
> + component_arr[count].comp_id.pcie_sbdf = comp;
> + component_arr[count].comp_synd.pcie_synd = synd;
> + break;
> + }
> + count++;
> + if (pos >= str_len)
> + break;
> + }
> + v5param->einjv2_struct.component_arr_count = count;
> +
> + /* clear buffer after user input for next injection */
> + memset(user_input, 0, COMP_ARR_SIZE);
> + } else {
-Tony
