efivarfs: Fix error on non-existent file

commit 2ab0837cb91b7de507daa145d17b3b6b2efb3abf upstream.

When looking up a non-existent file, efivarfs returns -EINVAL if the
file does not conform to the NAME-GUID format and -ENOENT if it does.
This is caused by efivars_d_hash() returning -EINVAL if the name is not
formatted correctly.  This error is returned before simple_lookup()
returns a negative dentry, and is the error value that the user sees.

Fix by removing this check.  If the file does not exist, simple_lookup()
will return a negative dentry leading to -ENOENT and efivarfs_create()
already has a validity check before it creates an entry (and will
correctly return -EINVAL)

Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: <stable@vger.kernel.org>
[ardb: make efivarfs_valid_name() static]
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/fs/efivarfs/inode.c b/fs/efivarfs/inode.c
index 0297ad95eb5cc01cafe158185e890b3ed214b40e..d022de1ce2c27931660adf6074af501ce7a1622d 100644 (file)
--- a/fs/efivarfs/inode.c
+++ b/fs/efivarfs/inode.c
@@ -43,7 +43,7 @@ struct inode *efivarfs_get_inode(struct super_block *sb,
  *
  *     VariableName-12345678-1234-1234-1234-1234567891bc
  */
-bool efivarfs_valid_name(const char *str, int len)
+static bool efivarfs_valid_name(const char *str, int len)
 {
        const char *s = str + len - EFI_VARIABLE_GUID_LEN;
 

diff --git a/fs/efivarfs/internal.h b/fs/efivarfs/internal.h
index 30ae44cb74531d1542bf942eb43f8cc5ef2d9051..16cbc73b6f37737857c60a20f17bb9eeb571ff67 100644 (file)
--- a/fs/efivarfs/internal.h
+++ b/fs/efivarfs/internal.h
@@ -10,7 +10,6 @@
 
 extern const struct file_operations efivarfs_file_operations;
 extern const struct inode_operations efivarfs_dir_inode_operations;
-extern bool efivarfs_valid_name(const char *str, int len);
 extern struct inode *efivarfs_get_inode(struct super_block *sb,
                        const struct inode *dir, int mode, dev_t dev,
                        bool is_removable);

diff --git a/fs/efivarfs/super.c b/fs/efivarfs/super.c
index 3626816b174ad7c53b0b40d4efa990c044d85204..99d002438008b8145e404e8d6e4bb580860a8d42 100644 (file)
--- a/fs/efivarfs/super.c
+++ b/fs/efivarfs/super.c
@@ -64,9 +64,6 @@ static int efivarfs_d_hash(const struct dentry *dentry, struct qstr *qstr)
        const unsigned char *s = qstr->name;
        unsigned int len = qstr->len;
 
-       if (!efivarfs_valid_name(s, len))
-               return -EINVAL;
-
        while (len-- > EFI_VARIABLE_GUID_LEN)
                hash = partial_name_hash(*s++, hash);