path: root/drivers
diff options
authorMatt Fleming <matt.fleming@intel.com>2013-03-05 07:40:16 +0000
committerMatt Fleming <matt.fleming@intel.com>2013-03-06 14:46:04 +0000
commit123abd76edf56c02a76b46d3d673897177ef067b (patch)
tree1aba3ae5759b447af561c6d296c4febb32f8dba8 /drivers
parent68d929862e29a8b52a7f2f2f86a0600423b093cd (diff)
efivars: efivarfs_valid_name() should handle pstore syntax
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> Cc: <stable@vger.kernel.org> # v3.8 Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Diffstat (limited to 'drivers')
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/firmware/efivars.c b/drivers/firmware/efivars.c
index 0d504971ed4..1b9a6e17e3d 100644
--- a/drivers/firmware/efivars.c
+++ b/drivers/firmware/efivars.c
@@ -974,8 +974,8 @@ 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;