ext4 crypto: handle unexpected lack of encryption keys

Fix up attempts by users to try to write to a file when they don't
have access to the encryption key.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
This commit is contained in:
Theodore Ts'o 2015-05-31 13:35:39 -04:00
parent 4d3c4e5b8c
commit abdd438b26
3 changed files with 14 additions and 9 deletions

View File

@ -104,7 +104,8 @@ struct ext4_crypto_ctx *ext4_get_crypto_ctx(struct inode *inode)
unsigned long flags;
struct ext4_crypt_info *ci = EXT4_I(inode)->i_crypt_info;
BUG_ON(ci == NULL);
if (ci == NULL)
return ERR_PTR(-ENOKEY);
/*
* We first try getting the ctx from a free list because in

View File

@ -183,7 +183,8 @@ int ext4_inherit_context(struct inode *parent, struct inode *child)
if (res < 0)
return res;
ci = EXT4_I(parent)->i_crypt_info;
BUG_ON(ci == NULL);
if (ci == NULL)
return -ENOKEY;
ctx.format = EXT4_ENCRYPTION_CONTEXT_FORMAT_V1;
if (DUMMY_ENCRYPTION_ENABLED(EXT4_SB(parent->i_sb))) {

View File

@ -226,6 +226,8 @@ static int ext4_file_mmap(struct file *file, struct vm_area_struct *vma)
int err = ext4_get_encryption_info(inode);
if (err)
return 0;
if (ext4_encryption_info(inode) == NULL)
return -ENOKEY;
}
file_accessed(file);
if (IS_DAX(file_inode(file))) {
@ -278,6 +280,13 @@ static int ext4_file_open(struct inode * inode, struct file * filp)
ext4_journal_stop(handle);
}
}
if (ext4_encrypted_inode(inode)) {
ret = ext4_get_encryption_info(inode);
if (ret)
return -EACCES;
if (ext4_encryption_info(inode) == NULL)
return -ENOKEY;
}
/*
* Set up the jbd2_inode if we are opening the inode for
* writing and the journal is present
@ -287,13 +296,7 @@ static int ext4_file_open(struct inode * inode, struct file * filp)
if (ret < 0)
return ret;
}
ret = dquot_file_open(inode, filp);
if (!ret && ext4_encrypted_inode(inode)) {
ret = ext4_get_encryption_info(inode);
if (ret)
ret = -EACCES;
}
return ret;
return dquot_file_open(inode, filp);
}
/*