summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorMatt Fleming <matt.fleming@intel.com>2013-03-05 07:40:16 +0000
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2013-03-14 11:26:25 -0700
commite59bcdae87ec116dde25da6d725f79fefb253693 (patch)
tree156062a0aa9a25f49b729f55138dae189d6eae90
parentc9fa7329af2e71971687a83ad1acaca31d73fd92 (diff)
efivars: efivarfs_valid_name() should handle pstore syntax
commit 123abd76edf56c02a76b46d3d673897177ef067b upstream. Stricter validation was introduced with commit da27a24383b2b ("efivarfs: guid part of filenames are case-insensitive") and commit 47f531e8ba3b ("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> Signed-off-by: Matt Fleming <matt.fleming@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r--drivers/firmware/efivars.c4
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/firmware/efivars.c b/drivers/firmware/efivars.c
index bcb201cd7db8..9d8867563c12 100644
--- a/drivers/firmware/efivars.c
+++ b/drivers/firmware/efivars.c
@@ -921,8 +921,8 @@ static bool efivarfs_valid_name(const char *str, int len)
if (len < GUID_LEN + 2)
return false;
- /* GUID should be right after the first '-' */
- if (s - 1 != strchr(str, '-'))
+ /* GUID must be preceded by a '-' */
+ if (*(s - 1) != '-')
return false;
/*