diff options
| author | Seiji Aguchi <seiji.aguchi@hds.com> | 2012-11-14 20:25:37 +0000 |
|---|---|---|
| committer | Ben Hutchings <ben@decadent.org.uk> | 2013-03-20 15:03:27 +0000 |
| commit | 316d0bb70f66a2682c19494f2d1fdebfa00de1ac (patch) | |
| tree | ab22d352664c4f4154ea4e4ed383eda89052c993 /drivers/firmware | |
| parent | 689901ce9cedd2d34a5404dda146d0604cbc2a5e (diff) | |
efi_pstore: Check remaining space with QueryVariableInfo() before writing data
commit d80a361d779a9f19498943d1ca84243209cd5647 upstream.
[Issue]
As discussed in a thread below, Running out of space in EFI isn't a well-tested scenario.
And we wouldn't expect all firmware to handle it gracefully.
http://marc.info/?l=linux-kernel&m=134305325801789&w=2
On the other hand, current efi_pstore doesn't check a remaining space of storage at writing time.
Therefore, efi_pstore may not work if it tries to write a large amount of data.
[Patch Description]
To avoid handling the situation above, this patch checks if there is a space enough to log with
QueryVariableInfo() before writing data.
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>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Diffstat (limited to 'drivers/firmware')
| -rw-r--r-- | drivers/firmware/efivars.c | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/drivers/firmware/efivars.c b/drivers/firmware/efivars.c index 5d5a8684377..0fd62b9dc9c 100644 --- a/drivers/firmware/efivars.c +++ b/drivers/firmware/efivars.c @@ -706,12 +706,29 @@ static int efi_pstore_write(enum pstore_type_id type, u64 *id, struct efivars *efivars = psi->data; struct efivar_entry *entry, *found = NULL; int i, ret = 0; + u64 storage_space, remaining_space, max_variable_size; + efi_status_t status = EFI_NOT_FOUND; sprintf(stub_name, "dump-type%u-%u-", type, part); sprintf(name, "%s%lu", stub_name, get_seconds()); spin_lock(&efivars->lock); + /* + * Check if there is a space enough to log. + * size: a size of logging data + * DUMP_NAME_LEN * 2: a maximum size of variable name + */ + status = efivars->ops->query_variable_info(PSTORE_EFI_ATTRIBUTES, + &storage_space, + &remaining_space, + &max_variable_size); + if (status || remaining_space < size + DUMP_NAME_LEN * 2) { + spin_unlock(&efivars->lock); + *id = part; + return -ENOSPC; + } + for (i = 0; i < DUMP_NAME_LEN; i++) efi_name[i] = stub_name[i]; @@ -1235,6 +1252,7 @@ efivars_init(void) ops.get_variable = efi.get_variable; ops.set_variable = efi.set_variable; ops.get_next_variable = efi.get_next_variable; + ops.query_variable_info = efi.query_variable_info; error = register_efivars(&__efivars, &ops, efi_kobj); if (error) goto err_put; |