efi_pstore: Add a format check for an existing variable name at erasing 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 erase 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 erase callback to make it erasable.
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>
diff --git a/drivers/firmware/efivars.c b/drivers/firmware/efivars.c
index bf7a6f9..6e51c1e 100644
--- a/drivers/firmware/efivars.c
+++ b/drivers/firmware/efivars.c
@@ -773,6 +773,8 @@
{
char name[DUMP_NAME_LEN];
efi_char16_t efi_name[DUMP_NAME_LEN];
+ char name_old[DUMP_NAME_LEN];
+ efi_char16_t efi_name_old[DUMP_NAME_LEN];
efi_guid_t vendor = LINUX_EFI_CRASH_GUID;
struct efivars *efivars = psi->data;
struct efivar_entry *entry, *found = NULL;
@@ -796,8 +798,22 @@
if (efi_guidcmp(entry->var.VendorGuid, vendor))
continue;
if (utf16_strncmp(entry->var.VariableName, efi_name,
- utf16_strlen(efi_name)))
- continue;
+ utf16_strlen(efi_name))) {
+ /*
+ * Check if an old format,
+ * which doesn't support holding
+ * multiple logs, remains.
+ */
+ sprintf(name_old, "dump-type%u-%u-%lu", type,
+ (unsigned int)id, time.tv_sec);
+
+ for (i = 0; i < DUMP_NAME_LEN; i++)
+ efi_name_old[i] = name_old[i];
+
+ if (utf16_strncmp(entry->var.VariableName, efi_name_old,
+ utf16_strlen(efi_name_old)))
+ continue;
+ }
/* found */
found = entry;