Commit Graph

4 Commits

Author SHA1 Message Date
Matt Fleming 123abd76ed efivars: efivarfs_valid_name() should handle pstore syntax
Stricter validation was introduced with commit da27a24383
("efivarfs: guid part of filenames are case-insensitive") and commit
47f531e8ba ("efivarfs: Validate filenames much more aggressively"),
which is necessary for the guid portion of efivarfs filenames, but we
don't need to be so strict with the first part, the variable name. The
UEFI specification doesn't impose any constraints on variable names
other than they be a NULL-terminated string.

The above commits caused a regression that resulted in users seeing
the following message,

  $ sudo mount -v /sys/firmware/efi/efivars mount: Cannot allocate memory

whenever pstore EFI variables were present in the variable store,
since their variable names failed to pass the following check,

    /* GUID should be right after the first '-' */
    if (s - 1 != strchr(str, '-'))

as a typical pstore filename is of the form, dump-type0-10-1-<guid>.
The fix is trivial since the guid portion of the filename is GUID_LEN
bytes, we can use (len - GUID_LEN) to ensure the '-' character is
where we expect it to be.

(The bogus ENOMEM error value will be fixed in a separate patch.)

Reported-by: Joseph Yasi <joe.yasi@gmail.com>
Tested-by: Joseph Yasi <joe.yasi@gmail.com>
Reported-by: Lingzhu Xiang <lxiang@redhat.com>
Cc: Josh Boyer <jwboyer@redhat.com>
Cc: Jeremy Kerr <jk@ozlabs.org>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: <stable@vger.kernel.org> # v3.8
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2013-03-06 14:46:04 +00:00
Jeremy Kerr d974f67a52 selftests/efivarfs: add create-read test
Test that reads from a newly-created efivarfs file (with no data written)
will return EOF.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Cc: Matt Fleming <matt.fleming@intel.com>
Cc: Lingzhu Xiang <lxiang@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-27 19:10:24 -08:00
Jeremy Kerr 033a1a7fe7 selftests/efivarfs: add empty file creation test
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Cc: Matt Fleming <matt.fleming@intel.com>
Cc: Lingzhu Xiang <lxiang@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-27 19:10:24 -08:00
Jeremy Kerr 455ce1c721 selftests: add tests for efivarfs
This change adds a few initial efivarfs tests to the
tools/testing/selftests directory.

The open-unlink test is based on code from Lingzhu Xiang.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Cc: Matt Fleming <matt.fleming@intel.com>
Cc: Lingzhu Xiang <lxiang@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-27 19:10:24 -08:00