efi_pstore: Add a format check for an existing variable name at reading time

[Issue]

a format of variable name has been updated to type, id, count and ctime
to support holding multiple logs.

Format of current variable name
  dump-type0-1-2-12345678

  type:0
  id:1
  count:2
  ctime:12345678

On the other hand, if an old variable name before being updated
remains, users can't read it via /dev/pstore.

Format of old variable name
  dump-type0-1-12345678

  type:0
  id:1
  ctime:12345678

[Solution]

This patch add a format check for the old variable name in a read callback
to make it readable.

Signed-off-by: Seiji Aguchi <seiji.aguchi@hds.com>
Acked-by: Mike Waychison <mikew@google.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
This commit is contained in:
Seiji Aguchi 2012-11-14 20:28:50 +00:00 committed by Tony Luck
parent 755d4fe465
commit 0f7de85a94
1 changed files with 28 additions and 10 deletions

View File

@ -681,17 +681,35 @@ static ssize_t efi_pstore_read(u64 *id, enum pstore_type_id *type,
*count = cnt;
timespec->tv_sec = time;
timespec->tv_nsec = 0;
get_var_data_locked(efivars, &efivars->walk_entry->var);
size = efivars->walk_entry->var.DataSize;
*buf = kmalloc(size, GFP_KERNEL);
if (*buf == NULL)
return -ENOMEM;
memcpy(*buf, efivars->walk_entry->var.Data,
size);
efivars->walk_entry = list_entry(efivars->walk_entry->list.next,
struct efivar_entry, list);
return size;
} else if (sscanf(name, "dump-type%u-%u-%lu",
type, &part, &time) == 3) {
/*
* Check if an old format,
* which doesn't support holding
* multiple logs, remains.
*/
*id = part;
*count = 0;
timespec->tv_sec = time;
timespec->tv_nsec = 0;
} else {
efivars->walk_entry = list_entry(
efivars->walk_entry->list.next,
struct efivar_entry, list);
continue;
}
get_var_data_locked(efivars, &efivars->walk_entry->var);
size = efivars->walk_entry->var.DataSize;
*buf = kmalloc(size, GFP_KERNEL);
if (*buf == NULL)
return -ENOMEM;
memcpy(*buf, efivars->walk_entry->var.Data,
size);
efivars->walk_entry = list_entry(
efivars->walk_entry->list.next,
struct efivar_entry, list);
return size;
}
efivars->walk_entry = list_entry(efivars->walk_entry->list.next,
struct efivar_entry, list);