summaryrefslogtreecommitdiff
path: root/fs/ecryptfs/inode.c
diff options
context:
space:
mode:
Diffstat (limited to 'fs/ecryptfs/inode.c')
-rw-r--r--fs/ecryptfs/inode.c24
1 files changed, 18 insertions, 6 deletions
diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c
index d8325263ba6e..93bc0f8174a7 100644
--- a/fs/ecryptfs/inode.c
+++ b/fs/ecryptfs/inode.c
@@ -640,8 +640,9 @@ static int
ecryptfs_readlink(struct dentry *dentry, char __user *buf, int bufsiz)
{
char *lower_buf;
+ size_t lower_bufsiz;
struct dentry *lower_dentry;
- struct ecryptfs_crypt_stat *crypt_stat;
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
char *plaintext_name;
size_t plaintext_name_size;
mm_segment_t old_fs;
@@ -652,12 +653,21 @@ ecryptfs_readlink(struct dentry *dentry, char __user *buf, int bufsiz)
rc = -EINVAL;
goto out;
}
- crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat;
+ mount_crypt_stat = &ecryptfs_superblock_to_private(
+ dentry->d_sb)->mount_crypt_stat;
+ /*
+ * If the lower filename is encrypted, it will result in a significantly
+ * longer name. If needed, truncate the name after decode and decrypt.
+ */
+ if (mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES)
+ lower_bufsiz = PATH_MAX;
+ else
+ lower_bufsiz = bufsiz;
/* Released in this function */
- lower_buf = kmalloc(bufsiz, GFP_KERNEL);
+ lower_buf = kmalloc(lower_bufsiz, GFP_KERNEL);
if (lower_buf == NULL) {
printk(KERN_ERR "%s: Out of memory whilst attempting to "
- "kmalloc [%d] bytes\n", __func__, bufsiz);
+ "kmalloc [%d] bytes\n", __func__, lower_bufsiz);
rc = -ENOMEM;
goto out;
}
@@ -665,7 +675,7 @@ ecryptfs_readlink(struct dentry *dentry, char __user *buf, int bufsiz)
set_fs(get_ds());
rc = lower_dentry->d_inode->i_op->readlink(lower_dentry,
(char __user *)lower_buf,
- bufsiz);
+ lower_bufsiz);
set_fs(old_fs);
if (rc >= 0) {
rc = ecryptfs_decode_and_decrypt_filename(&plaintext_name,
@@ -678,7 +688,9 @@ ecryptfs_readlink(struct dentry *dentry, char __user *buf, int bufsiz)
rc);
goto out_free_lower_buf;
}
- rc = copy_to_user(buf, plaintext_name, plaintext_name_size);
+ /* Check for bufsiz <= 0 done in sys_readlinkat() */
+ rc = copy_to_user(buf, plaintext_name,
+ min((unsigned) bufsiz, plaintext_name_size));
if (rc)
rc = -EFAULT;
else