eCryptfs: Handle NULL nameidata pointers

Allow for NULL nameidata pointers in eCryptfs create, lookup, and
d_revalidate functions.

Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
This commit is contained in:
Tyler Hicks 2011-02-17 17:35:20 -06:00
parent 8787c7a3e0
commit 70b8902199
3 changed files with 29 additions and 26 deletions

View file

@ -46,24 +46,28 @@ static int ecryptfs_d_revalidate(struct dentry *dentry, struct nameidata *nd)
{ {
struct dentry *lower_dentry; struct dentry *lower_dentry;
struct vfsmount *lower_mnt; struct vfsmount *lower_mnt;
struct dentry *dentry_save; struct dentry *dentry_save = NULL;
struct vfsmount *vfsmount_save; struct vfsmount *vfsmount_save = NULL;
int rc = 1; int rc = 1;
if (nd->flags & LOOKUP_RCU) if (nd && nd->flags & LOOKUP_RCU)
return -ECHILD; return -ECHILD;
lower_dentry = ecryptfs_dentry_to_lower(dentry); lower_dentry = ecryptfs_dentry_to_lower(dentry);
lower_mnt = ecryptfs_dentry_to_lower_mnt(dentry); lower_mnt = ecryptfs_dentry_to_lower_mnt(dentry);
if (!lower_dentry->d_op || !lower_dentry->d_op->d_revalidate) if (!lower_dentry->d_op || !lower_dentry->d_op->d_revalidate)
goto out; goto out;
dentry_save = nd->path.dentry; if (nd) {
vfsmount_save = nd->path.mnt; dentry_save = nd->path.dentry;
nd->path.dentry = lower_dentry; vfsmount_save = nd->path.mnt;
nd->path.mnt = lower_mnt; nd->path.dentry = lower_dentry;
nd->path.mnt = lower_mnt;
}
rc = lower_dentry->d_op->d_revalidate(lower_dentry, nd); rc = lower_dentry->d_op->d_revalidate(lower_dentry, nd);
nd->path.dentry = dentry_save; if (nd) {
nd->path.mnt = vfsmount_save; nd->path.dentry = dentry_save;
nd->path.mnt = vfsmount_save;
}
if (dentry->d_inode) { if (dentry->d_inode) {
struct inode *lower_inode = struct inode *lower_inode =
ecryptfs_inode_to_lower(dentry->d_inode); ecryptfs_inode_to_lower(dentry->d_inode);

View file

@ -632,8 +632,7 @@ int ecryptfs_interpose(struct dentry *hidden_dentry,
u32 flags); u32 flags);
int ecryptfs_lookup_and_interpose_lower(struct dentry *ecryptfs_dentry, int ecryptfs_lookup_and_interpose_lower(struct dentry *ecryptfs_dentry,
struct dentry *lower_dentry, struct dentry *lower_dentry,
struct inode *ecryptfs_dir_inode, struct inode *ecryptfs_dir_inode);
struct nameidata *ecryptfs_nd);
int ecryptfs_decode_and_decrypt_filename(char **decrypted_name, int ecryptfs_decode_and_decrypt_filename(char **decrypted_name,
size_t *decrypted_name_size, size_t *decrypted_name_size,
struct dentry *ecryptfs_dentry, struct dentry *ecryptfs_dentry,

View file

@ -74,16 +74,20 @@ ecryptfs_create_underlying_file(struct inode *lower_dir_inode,
unsigned int flags_save; unsigned int flags_save;
int rc; int rc;
dentry_save = nd->path.dentry; if (nd) {
vfsmount_save = nd->path.mnt; dentry_save = nd->path.dentry;
flags_save = nd->flags; vfsmount_save = nd->path.mnt;
nd->path.dentry = lower_dentry; flags_save = nd->flags;
nd->path.mnt = lower_mnt; nd->path.dentry = lower_dentry;
nd->flags &= ~LOOKUP_OPEN; nd->path.mnt = lower_mnt;
nd->flags &= ~LOOKUP_OPEN;
}
rc = vfs_create(lower_dir_inode, lower_dentry, mode, nd); rc = vfs_create(lower_dir_inode, lower_dentry, mode, nd);
nd->path.dentry = dentry_save; if (nd) {
nd->path.mnt = vfsmount_save; nd->path.dentry = dentry_save;
nd->flags = flags_save; nd->path.mnt = vfsmount_save;
nd->flags = flags_save;
}
return rc; return rc;
} }
@ -241,8 +245,7 @@ ecryptfs_create(struct inode *directory_inode, struct dentry *ecryptfs_dentry,
*/ */
int ecryptfs_lookup_and_interpose_lower(struct dentry *ecryptfs_dentry, int ecryptfs_lookup_and_interpose_lower(struct dentry *ecryptfs_dentry,
struct dentry *lower_dentry, struct dentry *lower_dentry,
struct inode *ecryptfs_dir_inode, struct inode *ecryptfs_dir_inode)
struct nameidata *ecryptfs_nd)
{ {
struct dentry *lower_dir_dentry; struct dentry *lower_dir_dentry;
struct vfsmount *lower_mnt; struct vfsmount *lower_mnt;
@ -290,8 +293,6 @@ int ecryptfs_lookup_and_interpose_lower(struct dentry *ecryptfs_dentry,
goto out; goto out;
if (special_file(lower_inode->i_mode)) if (special_file(lower_inode->i_mode))
goto out; goto out;
if (!ecryptfs_nd)
goto out;
/* Released in this function */ /* Released in this function */
page_virt = kmem_cache_zalloc(ecryptfs_header_cache_2, GFP_USER); page_virt = kmem_cache_zalloc(ecryptfs_header_cache_2, GFP_USER);
if (!page_virt) { if (!page_virt) {
@ -417,8 +418,7 @@ static struct dentry *ecryptfs_lookup(struct inode *ecryptfs_dir_inode,
} }
lookup_and_interpose: lookup_and_interpose:
rc = ecryptfs_lookup_and_interpose_lower(ecryptfs_dentry, lower_dentry, rc = ecryptfs_lookup_and_interpose_lower(ecryptfs_dentry, lower_dentry,
ecryptfs_dir_inode, ecryptfs_dir_inode);
ecryptfs_nd);
goto out; goto out;
out_d_drop: out_d_drop:
d_drop(ecryptfs_dentry); d_drop(ecryptfs_dentry);