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Merge branch 'work.ecryptfs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Browse Source 
Pull exryptfs updates from Al Viro:
 "The interesting part here is (ecryptfs) lock_parent() fixes - its
  treatment of ->d_parent had been very wrong.

  The rest is trivial cleanups"

* 'work.ecryptfs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  ecryptfs: ecryptfs_dentry_info->crypt_stat is never used
  ecryptfs: get rid of unused accessors
  ecryptfs: saner API for lock_parent()
  ecryptfs: get rid of pointless dget/dput in ->symlink() and ->link()
This commit is contained in:
Linus Torvalds 2021-05-02 09:05:54 -07:00
commit b28866f4bb
2 changed files with 75 additions and 105 deletions
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17
fs/ecryptfs/ecryptfs_kernel.h
View File

@ -262,10 +262,7 @@ struct ecryptfs_inode_info {
* vfsmount too. */
struct ecryptfs_dentry_info {
struct path lower_path;
union {
struct ecryptfs_crypt_stat *crypt_stat;
struct rcu_head rcu;
};
struct rcu_head rcu;
};
/**
@ -496,12 +493,6 @@ ecryptfs_set_superblock_lower(struct super_block *sb,
((struct ecryptfs_sb_info *)sb->s_fs_info)->wsi_sb = lower_sb;
}
static inline struct ecryptfs_dentry_info *
ecryptfs_dentry_to_private(struct dentry *dentry)
{
return (struct ecryptfs_dentry_info *)dentry->d_fsdata;
}
static inline void
ecryptfs_set_dentry_private(struct dentry *dentry,
struct ecryptfs_dentry_info *dentry_info)
@ -515,12 +506,6 @@ ecryptfs_dentry_to_lower(struct dentry *dentry)
return ((struct ecryptfs_dentry_info *)dentry->d_fsdata)->lower_path.dentry;
}
static inline struct vfsmount *
ecryptfs_dentry_to_lower_mnt(struct dentry *dentry)
{
return ((struct ecryptfs_dentry_info *)dentry->d_fsdata)->lower_path.mnt;
}
static inline struct path *
ecryptfs_dentry_to_lower_path(struct dentry *dentry)
{

163
fs/ecryptfs/inode.c
View File

@ -22,19 +22,18 @@
#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)
@ -128,32 +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(&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;
@ -177,13 +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(&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);
@ -193,14 +189,13 @@ 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;
}
@ -431,32 +426,28 @@ 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, &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);
dput(lower_new_dentry);
dput(lower_old_dentry);
inode_unlock(lower_dir);
return rc;
}
@ -471,14 +462,14 @@ 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);
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,
@ -487,7 +478,7 @@ 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))
@ -495,11 +486,10 @@ 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);
dput(lower_dentry);
inode_unlock(lower_dir);
if (d_really_is_negative(dentry))
d_drop(dentry);
return rc;
@ -510,22 +500,22 @@ 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;
@ -534,29 +524,24 @@ 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;
@ -568,21 +553,21 @@ 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;