nfsd: move some of fh_compose into helper functions

[safe/jmp/linux-2.6] / fs / ecryptfs / inode.c

diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c
index 55b3145..2f0945d 100644 (file)
--- a/fs/ecryptfs/inode.c
+++ b/fs/ecryptfs/inode.c
@@ -379,9 +379,11 @@ static struct dentry *ecryptfs_lookup(struct inode *ecryptfs_dir_inode,
                goto out_d_drop;
        }
        lower_dir_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry->d_parent);
+       mutex_lock(&lower_dir_dentry->d_inode->i_mutex);
        lower_dentry = lookup_one_len(ecryptfs_dentry->d_name.name,
                                      lower_dir_dentry,
                                      ecryptfs_dentry->d_name.len);
+       mutex_unlock(&lower_dir_dentry->d_inode->i_mutex);
        if (IS_ERR(lower_dentry)) {
                rc = PTR_ERR(lower_dentry);
                printk(KERN_ERR "%s: lookup_one_len() returned [%d] on "
@@ -406,9 +408,11 @@ static struct dentry *ecryptfs_lookup(struct inode *ecryptfs_dir_inode,
                       "filename; rc = [%d]\n", __func__, rc);
                goto out_d_drop;
        }
+       mutex_lock(&lower_dir_dentry->d_inode->i_mutex);
        lower_dentry = lookup_one_len(encrypted_and_encoded_name,
                                      lower_dir_dentry,
                                      encrypted_and_encoded_name_size - 1);
+       mutex_unlock(&lower_dir_dentry->d_inode->i_mutex);
        if (IS_ERR(lower_dentry)) {
                rc = PTR_ERR(lower_dentry);
                printk(KERN_ERR "%s: lookup_one_len() returned [%d] on "
@@ -636,8 +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;
@@ -648,12 +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 [%zd] bytes\n", __func__, lower_bufsiz);
                rc = -ENOMEM;
                goto out;
        }
@@ -661,7 +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,
@@ -674,7 +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((size_t) bufsiz, plaintext_name_size));
                if (rc)
                        rc = -EFAULT;
                else
@@ -814,6 +830,13 @@ int ecryptfs_truncate(struct dentry *dentry, loff_t new_length)
                size_t num_zeros = (PAGE_CACHE_SIZE
                                    - (new_length & ~PAGE_CACHE_MASK));
 
+               if (!(crypt_stat->flags & ECRYPTFS_ENCRYPTED)) {
+                       rc = vmtruncate(inode, new_length);
+                       if (rc)
+                               goto out_free;
+                       rc = vmtruncate(lower_dentry->d_inode, new_length);
+                       goto out_free;
+               }
                if (num_zeros) {
                        char *zeros_virt;
 
@@ -915,8 +938,6 @@ static int ecryptfs_setattr(struct dentry *dentry, struct iattr *ia)
                        }
                        rc = 0;
                        crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED);
-                       mutex_unlock(&crypt_stat->cs_mutex);
-                       goto out;
                }
        }
        mutex_unlock(&crypt_stat->cs_mutex);