diff options
Diffstat (limited to 'fs/ecryptfs')
-rw-r--r-- | fs/ecryptfs/inode.c | 157 |
1 files changed, 74 insertions, 83 deletions
diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c index 689aa493e587..861a01713f3f 100644 --- a/fs/ecryptfs/inode.c +++ b/fs/ecryptfs/inode.c @@ -21,19 +21,18 @@ #include <asm/unaligned.h> #include "ecryptfs_kernel.h" -static struct dentry *lock_parent(struct dentry *dentry) +static int lock_parent(struct dentry *dentry, + struct dentry **lower_dentry, + struct inode **lower_dir) { - struct dentry *dir; + struct dentry *lower_dir_dentry; - dir = dget_parent(dentry); - inode_lock_nested(d_inode(dir), I_MUTEX_PARENT); - return dir; -} + lower_dir_dentry = ecryptfs_dentry_to_lower(dentry->d_parent); + *lower_dir = d_inode(lower_dir_dentry); + *lower_dentry = ecryptfs_dentry_to_lower(dentry); -static void unlock_dir(struct dentry *dir) -{ - inode_unlock(d_inode(dir)); - dput(dir); + inode_lock_nested(*lower_dir, I_MUTEX_PARENT); + return (*lower_dentry)->d_parent == lower_dir_dentry ? 0 : -EINVAL; } static int ecryptfs_inode_test(struct inode *inode, void *lower_inode) @@ -127,32 +126,29 @@ static int ecryptfs_interpose(struct dentry *lower_dentry, static int ecryptfs_do_unlink(struct inode *dir, struct dentry *dentry, struct inode *inode) { - struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry); - struct dentry *lower_dir_dentry; - struct inode *lower_dir_inode; + struct dentry *lower_dentry; + struct inode *lower_dir; int rc; - lower_dir_dentry = ecryptfs_dentry_to_lower(dentry->d_parent); - lower_dir_inode = d_inode(lower_dir_dentry); - inode_lock_nested(lower_dir_inode, I_MUTEX_PARENT); + rc = lock_parent(dentry, &lower_dentry, &lower_dir); dget(lower_dentry); // don't even try to make the lower negative - if (lower_dentry->d_parent != lower_dir_dentry) - rc = -EINVAL; - else if (d_unhashed(lower_dentry)) - rc = -EINVAL; - else - rc = vfs_unlink(&init_user_ns, lower_dir_inode, lower_dentry, - NULL); + if (!rc) { + if (d_unhashed(lower_dentry)) + rc = -EINVAL; + else + rc = vfs_unlink(&init_user_ns, lower_dir, lower_dentry, + NULL); + } if (rc) { printk(KERN_ERR "Error in vfs_unlink; rc = [%d]\n", rc); goto out_unlock; } - fsstack_copy_attr_times(dir, lower_dir_inode); + fsstack_copy_attr_times(dir, lower_dir); set_nlink(inode, ecryptfs_inode_to_lower(inode)->i_nlink); inode->i_ctime = dir->i_ctime; out_unlock: dput(lower_dentry); - inode_unlock(lower_dir_inode); + inode_unlock(lower_dir); if (!rc) d_drop(dentry); return rc; @@ -176,13 +172,13 @@ ecryptfs_do_create(struct inode *directory_inode, { int rc; struct dentry *lower_dentry; - struct dentry *lower_dir_dentry; + struct inode *lower_dir; struct inode *inode; - lower_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry); - lower_dir_dentry = lock_parent(lower_dentry); - rc = vfs_create(&init_user_ns, d_inode(lower_dir_dentry), lower_dentry, - mode, true); + rc = lock_parent(ecryptfs_dentry, &lower_dentry, &lower_dir); + if (!rc) + rc = vfs_create(&init_user_ns, lower_dir, + lower_dentry, mode, true); if (rc) { printk(KERN_ERR "%s: Failure to create dentry in lower fs; " "rc = [%d]\n", __func__, rc); @@ -192,14 +188,13 @@ ecryptfs_do_create(struct inode *directory_inode, inode = __ecryptfs_get_inode(d_inode(lower_dentry), directory_inode->i_sb); if (IS_ERR(inode)) { - vfs_unlink(&init_user_ns, d_inode(lower_dir_dentry), - lower_dentry, NULL); + vfs_unlink(&init_user_ns, lower_dir, lower_dentry, NULL); goto out_lock; } - fsstack_copy_attr_times(directory_inode, d_inode(lower_dir_dentry)); - fsstack_copy_inode_size(directory_inode, d_inode(lower_dir_dentry)); + fsstack_copy_attr_times(directory_inode, lower_dir); + fsstack_copy_inode_size(directory_inode, lower_dir); out_lock: - unlock_dir(lower_dir_dentry); + inode_unlock(lower_dir); return inode; } @@ -430,28 +425,28 @@ static int ecryptfs_link(struct dentry *old_dentry, struct inode *dir, { struct dentry *lower_old_dentry; struct dentry *lower_new_dentry; - struct dentry *lower_dir_dentry; + struct inode *lower_dir; u64 file_size_save; int rc; file_size_save = i_size_read(d_inode(old_dentry)); lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry); - lower_new_dentry = ecryptfs_dentry_to_lower(new_dentry); - lower_dir_dentry = lock_parent(lower_new_dentry); - rc = vfs_link(lower_old_dentry, &init_user_ns, - d_inode(lower_dir_dentry), lower_new_dentry, NULL); + rc = lock_parent(new_dentry, &lower_new_dentry, &lower_dir); + if (!rc) + rc = vfs_link(lower_old_dentry, &init_user_ns, lower_dir, + lower_new_dentry, NULL); if (rc || d_really_is_negative(lower_new_dentry)) goto out_lock; rc = ecryptfs_interpose(lower_new_dentry, new_dentry, dir->i_sb); if (rc) goto out_lock; - fsstack_copy_attr_times(dir, d_inode(lower_dir_dentry)); - fsstack_copy_inode_size(dir, d_inode(lower_dir_dentry)); + fsstack_copy_attr_times(dir, lower_dir); + fsstack_copy_inode_size(dir, lower_dir); set_nlink(d_inode(old_dentry), ecryptfs_inode_to_lower(d_inode(old_dentry))->i_nlink); i_size_write(d_inode(new_dentry), file_size_save); out_lock: - unlock_dir(lower_dir_dentry); + inode_unlock(lower_dir); return rc; } @@ -466,13 +461,14 @@ static int ecryptfs_symlink(struct user_namespace *mnt_userns, { int rc; struct dentry *lower_dentry; - struct dentry *lower_dir_dentry; + struct inode *lower_dir; char *encoded_symname; size_t encoded_symlen; struct ecryptfs_mount_crypt_stat *mount_crypt_stat = NULL; - lower_dentry = ecryptfs_dentry_to_lower(dentry); - lower_dir_dentry = lock_parent(lower_dentry); + rc = lock_parent(dentry, &lower_dentry, &lower_dir); + if (rc) + goto out_lock; mount_crypt_stat = &ecryptfs_superblock_to_private( dir->i_sb)->mount_crypt_stat; rc = ecryptfs_encrypt_and_encode_filename(&encoded_symname, @@ -481,7 +477,7 @@ static int ecryptfs_symlink(struct user_namespace *mnt_userns, strlen(symname)); if (rc) goto out_lock; - rc = vfs_symlink(&init_user_ns, d_inode(lower_dir_dentry), lower_dentry, + rc = vfs_symlink(&init_user_ns, lower_dir, lower_dentry, encoded_symname); kfree(encoded_symname); if (rc || d_really_is_negative(lower_dentry)) @@ -489,10 +485,10 @@ static int ecryptfs_symlink(struct user_namespace *mnt_userns, rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb); if (rc) goto out_lock; - fsstack_copy_attr_times(dir, d_inode(lower_dir_dentry)); - fsstack_copy_inode_size(dir, d_inode(lower_dir_dentry)); + fsstack_copy_attr_times(dir, lower_dir); + fsstack_copy_inode_size(dir, lower_dir); out_lock: - unlock_dir(lower_dir_dentry); + inode_unlock(lower_dir); if (d_really_is_negative(dentry)) d_drop(dentry); return rc; @@ -503,22 +499,22 @@ static int ecryptfs_mkdir(struct user_namespace *mnt_userns, struct inode *dir, { int rc; struct dentry *lower_dentry; - struct dentry *lower_dir_dentry; + struct inode *lower_dir; - lower_dentry = ecryptfs_dentry_to_lower(dentry); - lower_dir_dentry = lock_parent(lower_dentry); - rc = vfs_mkdir(&init_user_ns, d_inode(lower_dir_dentry), lower_dentry, - mode); + rc = lock_parent(dentry, &lower_dentry, &lower_dir); + if (!rc) + rc = vfs_mkdir(&init_user_ns, lower_dir, + lower_dentry, mode); if (rc || d_really_is_negative(lower_dentry)) goto out; rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb); if (rc) goto out; - fsstack_copy_attr_times(dir, d_inode(lower_dir_dentry)); - fsstack_copy_inode_size(dir, d_inode(lower_dir_dentry)); - set_nlink(dir, d_inode(lower_dir_dentry)->i_nlink); + fsstack_copy_attr_times(dir, lower_dir); + fsstack_copy_inode_size(dir, lower_dir); + set_nlink(dir, lower_dir->i_nlink); out: - unlock_dir(lower_dir_dentry); + inode_unlock(lower_dir); if (d_really_is_negative(dentry)) d_drop(dentry); return rc; @@ -527,29 +523,24 @@ out: static int ecryptfs_rmdir(struct inode *dir, struct dentry *dentry) { struct dentry *lower_dentry; - struct dentry *lower_dir_dentry; - struct inode *lower_dir_inode; + struct inode *lower_dir; int rc; - lower_dentry = ecryptfs_dentry_to_lower(dentry); - lower_dir_dentry = ecryptfs_dentry_to_lower(dentry->d_parent); - lower_dir_inode = d_inode(lower_dir_dentry); - - inode_lock_nested(lower_dir_inode, I_MUTEX_PARENT); + rc = lock_parent(dentry, &lower_dentry, &lower_dir); dget(lower_dentry); // don't even try to make the lower negative - if (lower_dentry->d_parent != lower_dir_dentry) - rc = -EINVAL; - else if (d_unhashed(lower_dentry)) - rc = -EINVAL; - else - rc = vfs_rmdir(&init_user_ns, lower_dir_inode, lower_dentry); + if (!rc) { + if (d_unhashed(lower_dentry)) + rc = -EINVAL; + else + rc = vfs_rmdir(&init_user_ns, lower_dir, lower_dentry); + } if (!rc) { clear_nlink(d_inode(dentry)); - fsstack_copy_attr_times(dir, lower_dir_inode); - set_nlink(dir, lower_dir_inode->i_nlink); + fsstack_copy_attr_times(dir, lower_dir); + set_nlink(dir, lower_dir->i_nlink); } dput(lower_dentry); - inode_unlock(lower_dir_inode); + inode_unlock(lower_dir); if (!rc) d_drop(dentry); return rc; @@ -561,21 +552,21 @@ ecryptfs_mknod(struct user_namespace *mnt_userns, struct inode *dir, { int rc; struct dentry *lower_dentry; - struct dentry *lower_dir_dentry; + struct inode *lower_dir; - lower_dentry = ecryptfs_dentry_to_lower(dentry); - lower_dir_dentry = lock_parent(lower_dentry); - rc = vfs_mknod(&init_user_ns, d_inode(lower_dir_dentry), lower_dentry, - mode, dev); + rc = lock_parent(dentry, &lower_dentry, &lower_dir); + if (!rc) + rc = vfs_mknod(&init_user_ns, lower_dir, + lower_dentry, mode, dev); if (rc || d_really_is_negative(lower_dentry)) goto out; rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb); if (rc) goto out; - fsstack_copy_attr_times(dir, d_inode(lower_dir_dentry)); - fsstack_copy_inode_size(dir, d_inode(lower_dir_dentry)); + fsstack_copy_attr_times(dir, lower_dir); + fsstack_copy_inode_size(dir, lower_dir); out: - unlock_dir(lower_dir_dentry); + inode_unlock(lower_dir); if (d_really_is_negative(dentry)) d_drop(dentry); return rc; |