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-rw-r--r--fs/ecryptfs/inode.c262
1 files changed, 147 insertions, 115 deletions
diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c
index e23752d9a79f..c214fe0981bd 100644
--- a/fs/ecryptfs/inode.c
+++ b/fs/ecryptfs/inode.c
@@ -1,5 +1,5 @@
// SPDX-License-Identifier: GPL-2.0-or-later
-/**
+/*
* eCryptfs: Linux filesystem encryption layer
*
* Copyright (C) 1997-2004 Erez Zadok
@@ -18,22 +18,22 @@
#include <linux/fs_stack.h>
#include <linux/slab.h>
#include <linux/xattr.h>
+#include <linux/fileattr.h>
#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)
@@ -127,31 +127,29 @@ 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(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;
@@ -175,12 +173,13 @@ 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(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);
@@ -190,17 +189,17 @@ 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(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;
}
-/**
+/*
* ecryptfs_initialize_file
*
* Cause the file to be changed from a basic empty file to an ecryptfs
@@ -243,10 +242,8 @@ out:
return rc;
}
-/**
+/*
* ecryptfs_create
- * @dir: The inode of the directory in which to create the file.
- * @dentry: The eCryptfs dentry
* @mode: The mode of the new file.
*
* Creates a new file.
@@ -254,7 +251,8 @@ out:
* Returns zero on success; non-zero on error condition
*/
static int
-ecryptfs_create(struct inode *directory_inode, struct dentry *ecryptfs_dentry,
+ecryptfs_create(struct user_namespace *mnt_userns,
+ struct inode *directory_inode, struct dentry *ecryptfs_dentry,
umode_t mode, bool excl)
{
struct inode *ecryptfs_inode;
@@ -313,13 +311,13 @@ static int ecryptfs_i_size_read(struct dentry *dentry, struct inode *inode)
return 0;
}
-/**
+/*
* ecryptfs_lookup_interpose - Dentry interposition for a lookup
*/
static struct dentry *ecryptfs_lookup_interpose(struct dentry *dentry,
struct dentry *lower_dentry)
{
- struct path *path = ecryptfs_dentry_to_lower_path(dentry->d_parent);
+ const struct path *path = ecryptfs_dentry_to_lower_path(dentry->d_parent);
struct inode *inode, *lower_inode;
struct ecryptfs_dentry_info *dentry_info;
int rc = 0;
@@ -426,32 +424,28 @@ 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);
- dget(lower_old_dentry);
- dget(lower_new_dentry);
- lower_dir_dentry = lock_parent(lower_new_dentry);
- rc = vfs_link(lower_old_dentry, 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);
- dput(lower_new_dentry);
- dput(lower_old_dentry);
+ inode_unlock(lower_dir);
return rc;
}
@@ -460,19 +454,20 @@ static int ecryptfs_unlink(struct inode *dir, struct dentry *dentry)
return ecryptfs_do_unlink(dir, dentry, d_inode(dentry));
}
-static int ecryptfs_symlink(struct inode *dir, struct dentry *dentry,
+static int ecryptfs_symlink(struct user_namespace *mnt_userns,
+ struct inode *dir, struct dentry *dentry,
const char *symname)
{
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);
- dget(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 +476,7 @@ static int ecryptfs_symlink(struct inode *dir, struct dentry *dentry,
strlen(symname));
if (rc)
goto out_lock;
- rc = vfs_symlink(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))
@@ -489,35 +484,36 @@ static int ecryptfs_symlink(struct inode *dir, struct dentry *dentry,
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);
- dput(lower_dentry);
+ inode_unlock(lower_dir);
if (d_really_is_negative(dentry))
d_drop(dentry);
return rc;
}
-static int ecryptfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
+static int ecryptfs_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
+ struct dentry *dentry, umode_t mode)
{
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(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;
@@ -526,62 +522,59 @@ 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(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;
}
static int
-ecryptfs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
+ecryptfs_mknod(struct user_namespace *mnt_userns, struct inode *dir,
+ struct dentry *dentry, umode_t mode, dev_t dev)
{
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(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;
}
static int
-ecryptfs_rename(struct inode *old_dir, struct dentry *old_dentry,
- struct inode *new_dir, struct dentry *new_dentry,
- unsigned int flags)
+ecryptfs_rename(struct user_namespace *mnt_userns, struct inode *old_dir,
+ struct dentry *old_dentry, struct inode *new_dir,
+ struct dentry *new_dentry, unsigned int flags)
{
int rc;
struct dentry *lower_old_dentry;
@@ -590,6 +583,7 @@ ecryptfs_rename(struct inode *old_dir, struct dentry *old_dentry,
struct dentry *lower_new_dir_dentry;
struct dentry *trap;
struct inode *target_inode;
+ struct renamedata rd = {};
if (flags)
return -EINVAL;
@@ -619,9 +613,14 @@ ecryptfs_rename(struct inode *old_dir, struct dentry *old_dentry,
rc = -ENOTEMPTY;
goto out_lock;
}
- rc = vfs_rename(d_inode(lower_old_dir_dentry), lower_old_dentry,
- d_inode(lower_new_dir_dentry), lower_new_dentry,
- NULL, 0);
+
+ rd.old_mnt_userns = &init_user_ns;
+ rd.old_dir = d_inode(lower_old_dir_dentry);
+ rd.old_dentry = lower_old_dentry;
+ rd.new_mnt_userns = &init_user_ns;
+ rd.new_dir = d_inode(lower_new_dir_dentry);
+ rd.new_dentry = lower_new_dentry;
+ rc = vfs_rename(&rd);
if (rc)
goto out_lock;
if (target_inode)
@@ -855,20 +854,24 @@ int ecryptfs_truncate(struct dentry *dentry, loff_t new_length)
struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
inode_lock(d_inode(lower_dentry));
- rc = notify_change(lower_dentry, &lower_ia, NULL);
+ rc = notify_change(&init_user_ns, lower_dentry,
+ &lower_ia, NULL);
inode_unlock(d_inode(lower_dentry));
}
return rc;
}
static int
-ecryptfs_permission(struct inode *inode, int mask)
+ecryptfs_permission(struct user_namespace *mnt_userns, struct inode *inode,
+ int mask)
{
- return inode_permission(ecryptfs_inode_to_lower(inode), mask);
+ return inode_permission(&init_user_ns,
+ ecryptfs_inode_to_lower(inode), mask);
}
/**
* ecryptfs_setattr
+ * @mnt_userns: user namespace of the target mount
* @dentry: dentry handle to the inode to modify
* @ia: Structure with flags of what to change and values
*
@@ -879,7 +882,8 @@ ecryptfs_permission(struct inode *inode, int mask)
* All other metadata changes will be passed right to the lower filesystem,
* and we will just update our inode to look like the lower.
*/
-static int ecryptfs_setattr(struct dentry *dentry, struct iattr *ia)
+static int ecryptfs_setattr(struct user_namespace *mnt_userns,
+ struct dentry *dentry, struct iattr *ia)
{
int rc = 0;
struct dentry *lower_dentry;
@@ -933,7 +937,7 @@ static int ecryptfs_setattr(struct dentry *dentry, struct iattr *ia)
}
mutex_unlock(&crypt_stat->cs_mutex);
- rc = setattr_prepare(dentry, ia);
+ rc = setattr_prepare(&init_user_ns, dentry, ia);
if (rc)
goto out;
if (ia->ia_valid & ATTR_SIZE) {
@@ -959,14 +963,15 @@ static int ecryptfs_setattr(struct dentry *dentry, struct iattr *ia)
lower_ia.ia_valid &= ~ATTR_MODE;
inode_lock(d_inode(lower_dentry));
- rc = notify_change(lower_dentry, &lower_ia, NULL);
+ rc = notify_change(&init_user_ns, lower_dentry, &lower_ia, NULL);
inode_unlock(d_inode(lower_dentry));
out:
fsstack_copy_attr_all(inode, lower_inode);
return rc;
}
-static int ecryptfs_getattr_link(const struct path *path, struct kstat *stat,
+static int ecryptfs_getattr_link(struct user_namespace *mnt_userns,
+ const struct path *path, struct kstat *stat,
u32 request_mask, unsigned int flags)
{
struct dentry *dentry = path->dentry;
@@ -975,7 +980,7 @@ static int ecryptfs_getattr_link(const struct path *path, struct kstat *stat,
mount_crypt_stat = &ecryptfs_superblock_to_private(
dentry->d_sb)->mount_crypt_stat;
- generic_fillattr(d_inode(dentry), stat);
+ generic_fillattr(&init_user_ns, d_inode(dentry), stat);
if (mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES) {
char *target;
size_t targetsiz;
@@ -991,7 +996,8 @@ static int ecryptfs_getattr_link(const struct path *path, struct kstat *stat,
return rc;
}
-static int ecryptfs_getattr(const struct path *path, struct kstat *stat,
+static int ecryptfs_getattr(struct user_namespace *mnt_userns,
+ const struct path *path, struct kstat *stat,
u32 request_mask, unsigned int flags)
{
struct dentry *dentry = path->dentry;
@@ -1003,7 +1009,7 @@ static int ecryptfs_getattr(const struct path *path, struct kstat *stat,
if (!rc) {
fsstack_copy_attr_all(d_inode(dentry),
ecryptfs_inode_to_lower(d_inode(dentry)));
- generic_fillattr(d_inode(dentry), stat);
+ generic_fillattr(&init_user_ns, d_inode(dentry), stat);
stat->blocks = lower_stat.blocks;
}
return rc;
@@ -1016,15 +1022,19 @@ ecryptfs_setxattr(struct dentry *dentry, struct inode *inode,
{
int rc;
struct dentry *lower_dentry;
+ struct inode *lower_inode;
lower_dentry = ecryptfs_dentry_to_lower(dentry);
- if (!(d_inode(lower_dentry)->i_opflags & IOP_XATTR)) {
+ lower_inode = d_inode(lower_dentry);
+ if (!(lower_inode->i_opflags & IOP_XATTR)) {
rc = -EOPNOTSUPP;
goto out;
}
- rc = vfs_setxattr(lower_dentry, name, value, size, flags);
+ inode_lock(lower_inode);
+ rc = __vfs_setxattr_locked(&init_user_ns, lower_dentry, name, value, size, flags, NULL);
+ inode_unlock(lower_inode);
if (!rc && inode)
- fsstack_copy_attr_all(inode, d_inode(lower_dentry));
+ fsstack_copy_attr_all(inode, lower_inode);
out:
return rc;
}
@@ -1087,12 +1097,29 @@ static int ecryptfs_removexattr(struct dentry *dentry, struct inode *inode,
goto out;
}
inode_lock(lower_inode);
- rc = __vfs_removexattr(lower_dentry, name);
+ rc = __vfs_removexattr(&init_user_ns, lower_dentry, name);
inode_unlock(lower_inode);
out:
return rc;
}
+static int ecryptfs_fileattr_get(struct dentry *dentry, struct fileattr *fa)
+{
+ return vfs_fileattr_get(ecryptfs_dentry_to_lower(dentry), fa);
+}
+
+static int ecryptfs_fileattr_set(struct user_namespace *mnt_userns,
+ struct dentry *dentry, struct fileattr *fa)
+{
+ struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
+ int rc;
+
+ rc = vfs_fileattr_set(&init_user_ns, lower_dentry, fa);
+ fsstack_copy_attr_all(d_inode(dentry), d_inode(lower_dentry));
+
+ return rc;
+}
+
const struct inode_operations ecryptfs_symlink_iops = {
.get_link = ecryptfs_get_link,
.permission = ecryptfs_permission,
@@ -1114,6 +1141,8 @@ const struct inode_operations ecryptfs_dir_iops = {
.permission = ecryptfs_permission,
.setattr = ecryptfs_setattr,
.listxattr = ecryptfs_listxattr,
+ .fileattr_get = ecryptfs_fileattr_get,
+ .fileattr_set = ecryptfs_fileattr_set,
};
const struct inode_operations ecryptfs_main_iops = {
@@ -1121,6 +1150,8 @@ const struct inode_operations ecryptfs_main_iops = {
.setattr = ecryptfs_setattr,
.getattr = ecryptfs_getattr,
.listxattr = ecryptfs_listxattr,
+ .fileattr_get = ecryptfs_fileattr_get,
+ .fileattr_set = ecryptfs_fileattr_set,
};
static int ecryptfs_xattr_get(const struct xattr_handler *handler,
@@ -1131,6 +1162,7 @@ static int ecryptfs_xattr_get(const struct xattr_handler *handler,
}
static int ecryptfs_xattr_set(const struct xattr_handler *handler,
+ struct user_namespace *mnt_userns,
struct dentry *dentry, struct inode *inode,
const char *name, const void *value, size_t size,
int flags)
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.