diff options
author | Peter Jones <pjones@redhat.com> | 2016-02-08 14:48:15 -0500 |
---|---|---|
committer | Matt Fleming <matt@codeblueprint.co.uk> | 2016-02-10 16:25:52 +0000 |
commit | ed8b0de5a33d2a2557dce7f9429dca8cb5bc5879 (patch) | |
tree | 1dcd2e49cc432ae312677ec47453ec3abc18f1d2 /fs/efivarfs/super.c | |
parent | 8282f5d9c17fe15a9e658c06e3f343efae1a2a2f (diff) | |
download | talos-obmc-linux-ed8b0de5a33d2a2557dce7f9429dca8cb5bc5879.tar.gz talos-obmc-linux-ed8b0de5a33d2a2557dce7f9429dca8cb5bc5879.zip |
efi: Make efivarfs entries immutable by default
"rm -rf" is bricking some peoples' laptops because of variables being
used to store non-reinitializable firmware driver data that's required
to POST the hardware.
These are 100% bugs, and they need to be fixed, but in the mean time it
shouldn't be easy to *accidentally* brick machines.
We have to have delete working, and picking which variables do and don't
work for deletion is quite intractable, so instead make everything
immutable by default (except for a whitelist), and make tools that
aren't quite so broad-spectrum unset the immutable flag.
Signed-off-by: Peter Jones <pjones@redhat.com>
Tested-by: Lee, Chun-Yi <jlee@suse.com>
Acked-by: Matthew Garrett <mjg59@coreos.com>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Diffstat (limited to 'fs/efivarfs/super.c')
-rw-r--r-- | fs/efivarfs/super.c | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/fs/efivarfs/super.c b/fs/efivarfs/super.c index 8651ac28ec0d..dd029d13ea61 100644 --- a/fs/efivarfs/super.c +++ b/fs/efivarfs/super.c @@ -120,6 +120,7 @@ static int efivarfs_callback(efi_char16_t *name16, efi_guid_t vendor, char *name; int len; int err = -ENOMEM; + bool is_removable = false; entry = kzalloc(sizeof(*entry), GFP_KERNEL); if (!entry) @@ -137,13 +138,17 @@ static int efivarfs_callback(efi_char16_t *name16, efi_guid_t vendor, ucs2_as_utf8(name, entry->var.VariableName, len); + if (efivar_variable_is_removable(entry->var.VendorGuid, name, len)) + is_removable = true; + name[len] = '-'; efi_guid_to_str(&entry->var.VendorGuid, name + len + 1); name[len + EFI_VARIABLE_GUID_LEN+1] = '\0'; - inode = efivarfs_get_inode(sb, d_inode(root), S_IFREG | 0644, 0); + inode = efivarfs_get_inode(sb, d_inode(root), S_IFREG | 0644, 0, + is_removable); if (!inode) goto fail_name; @@ -199,7 +204,7 @@ static int efivarfs_fill_super(struct super_block *sb, void *data, int silent) sb->s_d_op = &efivarfs_d_ops; sb->s_time_gran = 1; - inode = efivarfs_get_inode(sb, NULL, S_IFDIR | 0755, 0); + inode = efivarfs_get_inode(sb, NULL, S_IFDIR | 0755, 0, true); if (!inode) return -ENOMEM; inode->i_op = &efivarfs_dir_inode_operations; |