#include <linux/slab.h>
#include <linux/fs.h>
#include <linux/namei.h>
-#include <linux/quotaops.h>
#include <linux/pagemap.h>
#include <linux/fsnotify.h>
#include <linux/personality.h>
#include "internal.h"
-#define ACC_MODE(x) ("\000\004\002\006"[(x)&O_ACCMODE])
-
/* [Feb-1997 T. Schoebel-Theuer]
* Fundamental changes in the pathname lookup mechanisms (namei)
* were necessary because of omirr. The reason is that omirr needs
/*
* Searching includes executable on directories, else just read.
*/
+ mask &= MAY_READ | MAY_WRITE | MAY_EXEC;
if (mask == MAY_READ || (S_ISDIR(inode->i_mode) && !(mask & MAY_WRITE)))
if (capable(CAP_DAC_READ_SEARCH))
return 0;
return dentry;
}
+/*
+ * force_reval_path - force revalidation of a dentry
+ *
+ * In some situations the path walking code will trust dentries without
+ * revalidating them. This causes problems for filesystems that depend on
+ * d_revalidate to handle file opens (e.g. NFSv4). When FS_REVAL_DOT is set
+ * (which indicates that it's possible for the dentry to go stale), force
+ * a d_revalidate call before proceeding.
+ *
+ * Returns 0 if the revalidation was successful. If the revalidation fails,
+ * either return the error returned by d_revalidate or -ESTALE if the
+ * revalidation it just returned 0. If d_revalidate returns 0, we attempt to
+ * invalidate the dentry. It's up to the caller to handle putting references
+ * to the path if necessary.
+ */
+static int
+force_reval_path(struct path *path, struct nameidata *nd)
+{
+ int status;
+ struct dentry *dentry = path->dentry;
+
+ /*
+ * only check on filesystems where it's possible for the dentry to
+ * become stale. It's assumed that if this flag is set then the
+ * d_revalidate op will also be defined.
+ */
+ if (!(dentry->d_sb->s_type->fs_flags & FS_REVAL_DOT))
+ return 0;
+
+ status = dentry->d_op->d_revalidate(dentry, nd);
+ if (status > 0)
+ return 0;
+
+ if (!status) {
+ d_invalidate(dentry);
+ status = -ESTALE;
+ }
+ return status;
+}
+
/*
* Short-cut version of permission(), for calling on directories
* during pathname resolution. Combines parts of permission()
static __always_inline int __vfs_follow_link(struct nameidata *nd, const char *link)
{
- int res = 0;
- char *name;
if (IS_ERR(link))
goto fail;
path_get(&nd->root);
}
- res = link_path_walk(link, nd);
- if (nd->depth || res || nd->last_type!=LAST_NORM)
- return res;
- /*
- * If it is an iterative symlinks resolution in open_namei() we
- * have to copy the last component. And all that crap because of
- * bloody create() on broken symlinks. Furrfu...
- */
- name = __getname();
- if (unlikely(!name)) {
- path_put(&nd->path);
- return -ENOMEM;
- }
- strcpy(name, nd->last.name);
- nd->last.name = name;
- return 0;
+ return link_path_walk(link, nd);
fail:
path_put(&nd->path);
return PTR_ERR(link);
nd->path.dentry = path->dentry;
}
-static __always_inline int __do_follow_link(struct path *path, struct nameidata *nd)
+static __always_inline int
+__do_follow_link(struct path *path, struct nameidata *nd, void **p)
{
int error;
- void *cookie;
struct dentry *dentry = path->dentry;
touch_atime(path->mnt, dentry);
dget(dentry);
}
mntget(path->mnt);
- cookie = dentry->d_inode->i_op->follow_link(dentry, nd);
- error = PTR_ERR(cookie);
- if (!IS_ERR(cookie)) {
+ nd->last_type = LAST_BIND;
+ *p = dentry->d_inode->i_op->follow_link(dentry, nd);
+ error = PTR_ERR(*p);
+ if (!IS_ERR(*p)) {
char *s = nd_get_link(nd);
error = 0;
if (s)
error = __vfs_follow_link(nd, s);
- if (dentry->d_inode->i_op->put_link)
- dentry->d_inode->i_op->put_link(dentry, nd, cookie);
+ else if (nd->last_type == LAST_BIND) {
+ error = force_reval_path(&nd->path, nd);
+ if (error)
+ path_put(&nd->path);
+ }
}
return error;
}
*/
static inline int do_follow_link(struct path *path, struct nameidata *nd)
{
+ void *cookie;
int err = -ELOOP;
if (current->link_count >= MAX_NESTED_LINKS)
goto loop;
current->link_count++;
current->total_link_count++;
nd->depth++;
- err = __do_follow_link(path, nd);
+ err = __do_follow_link(path, nd, &cookie);
+ if (!IS_ERR(cookie) && path->dentry->d_inode->i_op->put_link)
+ path->dentry->d_inode->i_op->put_link(path->dentry, nd, cookie);
path_put(path);
current->link_count--;
nd->depth--;
set_root(nd);
while(1) {
- struct vfsmount *parent;
struct dentry *old = nd->path.dentry;
if (nd->path.dentry == nd->root.dentry &&
nd->path.mnt == nd->root.mnt) {
break;
}
- spin_lock(&dcache_lock);
if (nd->path.dentry != nd->path.mnt->mnt_root) {
- nd->path.dentry = dget(nd->path.dentry->d_parent);
- spin_unlock(&dcache_lock);
+ /* rare case of legitimate dget_parent()... */
+ nd->path.dentry = dget_parent(nd->path.dentry);
dput(old);
break;
}
- spin_unlock(&dcache_lock);
- spin_lock(&vfsmount_lock);
- parent = nd->path.mnt->mnt_parent;
- if (parent == nd->path.mnt) {
- spin_unlock(&vfsmount_lock);
+ if (!follow_up(&nd->path))
break;
- }
- mntget(parent);
- nd->path.dentry = dget(nd->path.mnt->mnt_mountpoint);
- spin_unlock(&vfsmount_lock);
- dput(old);
- mntput(nd->path.mnt);
- nd->path.mnt = parent;
}
follow_mount(&nd->path);
}
return PTR_ERR(dentry);
}
+/*
+ * This is a temporary kludge to deal with "automount" symlinks; proper
+ * solution is to trigger them on follow_mount(), so that do_lookup()
+ * would DTRT. To be killed before 2.6.34-final.
+ */
+static inline int follow_on_final(struct inode *inode, unsigned lookup_flags)
+{
+ return inode && unlikely(inode->i_op->follow_link) &&
+ ((lookup_flags & LOOKUP_FOLLOW) || S_ISDIR(inode->i_mode));
+}
+
/*
* Name resolution.
* This is the basic name resolution function, turning a pathname into
if (err)
break;
inode = next.dentry->d_inode;
- if ((lookup_flags & LOOKUP_FOLLOW)
- && inode && inode->i_op->follow_link) {
+ if (follow_on_final(inode, lookup_flags)) {
err = do_follow_link(&next, nd);
if (err)
goto return_err;
return -ENOENT;
BUG_ON(victim->d_parent->d_inode != dir);
- audit_inode_child(victim->d_name.name, victim, dir);
+ audit_inode_child(victim, dir);
error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
if (error)
return inode_permission(dir, MAY_WRITE | MAY_EXEC);
}
-/*
- * O_DIRECTORY translates into forcing a directory lookup.
- */
-static inline int lookup_flags(unsigned int f)
-{
- unsigned long retval = LOOKUP_FOLLOW;
-
- if (f & O_NOFOLLOW)
- retval &= ~LOOKUP_FOLLOW;
-
- if (f & O_DIRECTORY)
- retval |= LOOKUP_DIRECTORY;
-
- return retval;
-}
-
/*
* p1 and p2 should be directories on the same fs.
*/
error = security_inode_create(dir, dentry, mode);
if (error)
return error;
- vfs_dq_init(dir);
error = dir->i_op->create(dir, dentry, mode, nd);
if (!error)
fsnotify_create(dir, dentry);
* An append-only file must be opened in append mode for writing.
*/
if (IS_APPEND(inode)) {
- if ((flag & FMODE_WRITE) && !(flag & O_APPEND))
+ if ((flag & O_ACCMODE) != O_RDONLY && !(flag & O_APPEND))
return -EPERM;
if (flag & O_TRUNC)
return -EPERM;
* what get passed to sys_open().
*/
static int __open_namei_create(struct nameidata *nd, struct path *path,
- int flag, int mode)
+ int open_flag, int mode)
{
int error;
struct dentry *dir = nd->path.dentry;
if (error)
return error;
/* Don't check for write permission, don't truncate */
- return may_open(&nd->path, 0, flag & ~O_TRUNC);
+ return may_open(&nd->path, 0, open_flag & ~O_TRUNC);
}
/*
return (flag & O_TRUNC);
}
-/*
- * Note that the low bits of the passed in "open_flag"
- * are not the same as in the local variable "flag". See
- * open_to_namei_flags() for more details.
- */
-struct file *do_filp_open(int dfd, const char *pathname,
- int open_flag, int mode, int acc_mode)
+static struct file *finish_open(struct nameidata *nd,
+ int open_flag, int acc_mode)
{
struct file *filp;
- struct nameidata nd;
- int error;
- struct path path, save;
- struct dentry *dir;
- int count = 0;
int will_truncate;
- int flag = open_to_namei_flags(open_flag);
+ int error;
+ will_truncate = open_will_truncate(open_flag, nd->path.dentry->d_inode);
+ if (will_truncate) {
+ error = mnt_want_write(nd->path.mnt);
+ if (error)
+ goto exit;
+ }
+ error = may_open(&nd->path, acc_mode, open_flag);
+ if (error) {
+ if (will_truncate)
+ mnt_drop_write(nd->path.mnt);
+ goto exit;
+ }
+ filp = nameidata_to_filp(nd);
+ if (!IS_ERR(filp)) {
+ error = ima_file_check(filp, acc_mode);
+ if (error) {
+ fput(filp);
+ filp = ERR_PTR(error);
+ }
+ }
+ if (!IS_ERR(filp)) {
+ if (will_truncate) {
+ error = handle_truncate(&nd->path);
+ if (error) {
+ fput(filp);
+ filp = ERR_PTR(error);
+ }
+ }
+ }
/*
- * O_SYNC is implemented as __O_SYNC|O_DSYNC. As many places only
- * check for O_DSYNC if the need any syncing at all we enforce it's
- * always set instead of having to deal with possibly weird behaviour
- * for malicious applications setting only __O_SYNC.
+ * It is now safe to drop the mnt write
+ * because the filp has had a write taken
+ * on its behalf.
*/
- if (open_flag & __O_SYNC)
- open_flag |= O_DSYNC;
-
- if (!acc_mode)
- acc_mode = MAY_OPEN | ACC_MODE(flag);
+ if (will_truncate)
+ mnt_drop_write(nd->path.mnt);
+ return filp;
- /* O_TRUNC implies we need access checks for write permissions */
- if (flag & O_TRUNC)
- acc_mode |= MAY_WRITE;
+exit:
+ if (!IS_ERR(nd->intent.open.file))
+ release_open_intent(nd);
+ path_put(&nd->path);
+ return ERR_PTR(error);
+}
- /* Allow the LSM permission hook to distinguish append
- access from general write access. */
- if (flag & O_APPEND)
- acc_mode |= MAY_APPEND;
+static struct file *do_last(struct nameidata *nd, struct path *path,
+ int open_flag, int acc_mode,
+ int mode, const char *pathname)
+{
+ struct dentry *dir = nd->path.dentry;
+ struct file *filp;
+ int error = -EISDIR;
- /*
- * The simplest case - just a plain lookup.
- */
- if (!(flag & O_CREAT)) {
- filp = get_empty_filp();
-
- if (filp == NULL)
- return ERR_PTR(-ENFILE);
- nd.intent.open.file = filp;
- nd.intent.open.flags = flag;
- nd.intent.open.create_mode = 0;
- error = do_path_lookup(dfd, pathname,
- lookup_flags(flag)|LOOKUP_OPEN, &nd);
- if (IS_ERR(nd.intent.open.file)) {
- if (error == 0) {
- error = PTR_ERR(nd.intent.open.file);
- path_put(&nd.path);
+ switch (nd->last_type) {
+ case LAST_DOTDOT:
+ follow_dotdot(nd);
+ dir = nd->path.dentry;
+ if (nd->path.mnt->mnt_sb->s_type->fs_flags & FS_REVAL_DOT) {
+ if (!dir->d_op->d_revalidate(dir, nd)) {
+ error = -ESTALE;
+ goto exit;
}
- } else if (error)
- release_open_intent(&nd);
- if (error)
- return ERR_PTR(error);
+ }
+ /* fallthrough */
+ case LAST_DOT:
+ case LAST_ROOT:
+ if (open_flag & O_CREAT)
+ goto exit;
+ /* fallthrough */
+ case LAST_BIND:
+ audit_inode(pathname, dir);
goto ok;
}
- /*
- * Create - we need to know the parent.
- */
- error = path_init(dfd, pathname, LOOKUP_PARENT, &nd);
- if (error)
- return ERR_PTR(error);
- error = path_walk(pathname, &nd);
- if (error) {
- if (nd.root.mnt)
- path_put(&nd.root);
- return ERR_PTR(error);
+ /* trailing slashes? */
+ if (nd->last.name[nd->last.len]) {
+ if (open_flag & O_CREAT)
+ goto exit;
+ nd->flags |= LOOKUP_DIRECTORY;
}
- if (unlikely(!audit_dummy_context()))
- audit_inode(pathname, nd.path.dentry);
- /*
- * We have the parent and last component. First of all, check
- * that we are not asked to creat(2) an obvious directory - that
- * will not do.
- */
- error = -EISDIR;
- if (nd.last_type != LAST_NORM || nd.last.name[nd.last.len])
- goto exit_parent;
+ /* just plain open? */
+ if (!(open_flag & O_CREAT)) {
+ error = do_lookup(nd, &nd->last, path);
+ if (error)
+ goto exit;
+ error = -ENOENT;
+ if (!path->dentry->d_inode)
+ goto exit_dput;
+ if (path->dentry->d_inode->i_op->follow_link)
+ return NULL;
+ error = -ENOTDIR;
+ if (nd->flags & LOOKUP_DIRECTORY) {
+ if (!path->dentry->d_inode->i_op->lookup)
+ goto exit_dput;
+ }
+ path_to_nameidata(path, nd);
+ audit_inode(pathname, nd->path.dentry);
+ goto ok;
+ }
- error = -ENFILE;
- filp = get_empty_filp();
- if (filp == NULL)
- goto exit_parent;
- nd.intent.open.file = filp;
- nd.intent.open.flags = flag;
- nd.intent.open.create_mode = mode;
- dir = nd.path.dentry;
- nd.flags &= ~LOOKUP_PARENT;
- nd.flags |= LOOKUP_CREATE | LOOKUP_OPEN;
- if (flag & O_EXCL)
- nd.flags |= LOOKUP_EXCL;
+ /* OK, it's O_CREAT */
mutex_lock(&dir->d_inode->i_mutex);
- path.dentry = lookup_hash(&nd);
- path.mnt = nd.path.mnt;
-do_last:
- error = PTR_ERR(path.dentry);
- if (IS_ERR(path.dentry)) {
+ path->dentry = lookup_hash(nd);
+ path->mnt = nd->path.mnt;
+
+ error = PTR_ERR(path->dentry);
+ if (IS_ERR(path->dentry)) {
mutex_unlock(&dir->d_inode->i_mutex);
goto exit;
}
- if (IS_ERR(nd.intent.open.file)) {
- error = PTR_ERR(nd.intent.open.file);
+ if (IS_ERR(nd->intent.open.file)) {
+ error = PTR_ERR(nd->intent.open.file);
goto exit_mutex_unlock;
}
/* Negative dentry, just create the file */
- if (!path.dentry->d_inode) {
+ if (!path->dentry->d_inode) {
/*
* This write is needed to ensure that a
* ro->rw transition does not occur between
* a permanent write count is taken through
* the 'struct file' in nameidata_to_filp().
*/
- error = mnt_want_write(nd.path.mnt);
+ error = mnt_want_write(nd->path.mnt);
if (error)
goto exit_mutex_unlock;
- error = __open_namei_create(&nd, &path, flag, mode);
+ error = __open_namei_create(nd, path, open_flag, mode);
if (error) {
- mnt_drop_write(nd.path.mnt);
+ mnt_drop_write(nd->path.mnt);
goto exit;
}
- filp = nameidata_to_filp(&nd, open_flag);
- mnt_drop_write(nd.path.mnt);
- if (nd.root.mnt)
- path_put(&nd.root);
+ filp = nameidata_to_filp(nd);
+ mnt_drop_write(nd->path.mnt);
if (!IS_ERR(filp)) {
- error = ima_path_check(&filp->f_path, filp->f_mode &
- (MAY_READ | MAY_WRITE | MAY_EXEC));
+ error = ima_file_check(filp, acc_mode);
if (error) {
fput(filp);
filp = ERR_PTR(error);
* It already exists.
*/
mutex_unlock(&dir->d_inode->i_mutex);
- audit_inode(pathname, path.dentry);
+ audit_inode(pathname, path->dentry);
error = -EEXIST;
- if (flag & O_EXCL)
+ if (open_flag & O_EXCL)
goto exit_dput;
- if (__follow_mount(&path)) {
+ if (__follow_mount(path)) {
error = -ELOOP;
- if (flag & O_NOFOLLOW)
+ if (open_flag & O_NOFOLLOW)
goto exit_dput;
}
error = -ENOENT;
- if (!path.dentry->d_inode)
+ if (!path->dentry->d_inode)
goto exit_dput;
- if (path.dentry->d_inode->i_op->follow_link)
- goto do_link;
- path_to_nameidata(&path, &nd);
+ if (path->dentry->d_inode->i_op->follow_link)
+ return NULL;
+
+ path_to_nameidata(path, nd);
error = -EISDIR;
- if (path.dentry->d_inode && S_ISDIR(path.dentry->d_inode->i_mode))
+ if (S_ISDIR(path->dentry->d_inode->i_mode))
goto exit;
ok:
- /*
- * Consider:
- * 1. may_open() truncates a file
- * 2. a rw->ro mount transition occurs
- * 3. nameidata_to_filp() fails due to
- * the ro mount.
- * That would be inconsistent, and should
- * be avoided. Taking this mnt write here
- * ensures that (2) can not occur.
- */
- will_truncate = open_will_truncate(flag, nd.path.dentry->d_inode);
- if (will_truncate) {
- error = mnt_want_write(nd.path.mnt);
- if (error)
- goto exit;
- }
- error = may_open(&nd.path, acc_mode, flag);
- if (error) {
- if (will_truncate)
- mnt_drop_write(nd.path.mnt);
- goto exit;
- }
- filp = nameidata_to_filp(&nd, open_flag);
- if (!IS_ERR(filp)) {
- error = ima_path_check(&filp->f_path, filp->f_mode &
- (MAY_READ | MAY_WRITE | MAY_EXEC));
- if (error) {
- fput(filp);
- filp = ERR_PTR(error);
- }
- }
- if (!IS_ERR(filp)) {
- if (acc_mode & MAY_WRITE)
- vfs_dq_init(nd.path.dentry->d_inode);
-
- if (will_truncate) {
- error = handle_truncate(&nd.path);
- if (error) {
- fput(filp);
- filp = ERR_PTR(error);
- }
- }
- }
- /*
- * It is now safe to drop the mnt write
- * because the filp has had a write taken
- * on its behalf.
- */
- if (will_truncate)
- mnt_drop_write(nd.path.mnt);
- if (nd.root.mnt)
- path_put(&nd.root);
+ filp = finish_open(nd, open_flag, acc_mode);
return filp;
exit_mutex_unlock:
mutex_unlock(&dir->d_inode->i_mutex);
exit_dput:
- path_put_conditional(&path, &nd);
+ path_put_conditional(path, nd);
exit:
- if (!IS_ERR(nd.intent.open.file))
- release_open_intent(&nd);
-exit_parent:
- if (nd.root.mnt)
- path_put(&nd.root);
- path_put(&nd.path);
+ if (!IS_ERR(nd->intent.open.file))
+ release_open_intent(nd);
+ path_put(&nd->path);
return ERR_PTR(error);
+}
+
+/*
+ * Note that the low bits of the passed in "open_flag"
+ * are not the same as in the local variable "flag". See
+ * open_to_namei_flags() for more details.
+ */
+struct file *do_filp_open(int dfd, const char *pathname,
+ int open_flag, int mode, int acc_mode)
+{
+ struct file *filp;
+ struct nameidata nd;
+ int error;
+ struct path path;
+ int count = 0;
+ int flag = open_to_namei_flags(open_flag);
+ int force_reval = 0;
+
+ if (!(open_flag & O_CREAT))
+ mode = 0;
-do_link:
- error = -ELOOP;
- if (flag & O_NOFOLLOW)
- goto exit_dput;
/*
- * This is subtle. Instead of calling do_follow_link() we do the
- * thing by hands. The reason is that this way we have zero link_count
- * and path_walk() (called from ->follow_link) honoring LOOKUP_PARENT.
- * After that we have the parent and last component, i.e.
- * we are in the same situation as after the first path_walk().
- * Well, almost - if the last component is normal we get its copy
- * stored in nd->last.name and we will have to putname() it when we
- * are done. Procfs-like symlinks just set LAST_BIND.
+ * O_SYNC is implemented as __O_SYNC|O_DSYNC. As many places only
+ * check for O_DSYNC if the need any syncing at all we enforce it's
+ * always set instead of having to deal with possibly weird behaviour
+ * for malicious applications setting only __O_SYNC.
*/
- nd.flags |= LOOKUP_PARENT;
- error = security_inode_follow_link(path.dentry, &nd);
+ if (open_flag & __O_SYNC)
+ open_flag |= O_DSYNC;
+
+ if (!acc_mode)
+ acc_mode = MAY_OPEN | ACC_MODE(open_flag);
+
+ /* O_TRUNC implies we need access checks for write permissions */
+ if (open_flag & O_TRUNC)
+ acc_mode |= MAY_WRITE;
+
+ /* Allow the LSM permission hook to distinguish append
+ access from general write access. */
+ if (open_flag & O_APPEND)
+ acc_mode |= MAY_APPEND;
+
+ /* find the parent */
+reval:
+ error = path_init(dfd, pathname, LOOKUP_PARENT, &nd);
if (error)
- goto exit_dput;
- save = nd.path;
- path_get(&save);
- error = __do_follow_link(&path, &nd);
- if (error == -ESTALE) {
- /* nd.path had been dropped */
- nd.path = save;
- path_get(&nd.path);
+ return ERR_PTR(error);
+ if (force_reval)
nd.flags |= LOOKUP_REVAL;
- error = __do_follow_link(&path, &nd);
- }
- path_put(&save);
- path_put(&path);
+
+ current->total_link_count = 0;
+ error = link_path_walk(pathname, &nd);
if (error) {
- /* Does someone understand code flow here? Or it is only
- * me so stupid? Anathema to whoever designed this non-sense
- * with "intent.open".
- */
- release_open_intent(&nd);
- if (nd.root.mnt)
- path_put(&nd.root);
- return ERR_PTR(error);
+ filp = ERR_PTR(error);
+ goto out;
}
+ if (unlikely(!audit_dummy_context()) && (open_flag & O_CREAT))
+ audit_inode(pathname, nd.path.dentry);
+
+ /*
+ * We have the parent and last component.
+ */
+
+ error = -ENFILE;
+ filp = get_empty_filp();
+ if (filp == NULL)
+ goto exit_parent;
+ nd.intent.open.file = filp;
+ filp->f_flags = open_flag;
+ nd.intent.open.flags = flag;
+ nd.intent.open.create_mode = mode;
nd.flags &= ~LOOKUP_PARENT;
- if (nd.last_type == LAST_BIND)
- goto ok;
- error = -EISDIR;
- if (nd.last_type != LAST_NORM)
- goto exit;
- if (nd.last.name[nd.last.len]) {
- __putname(nd.last.name);
- goto exit;
+ nd.flags |= LOOKUP_OPEN;
+ if (open_flag & O_CREAT) {
+ nd.flags |= LOOKUP_CREATE;
+ if (open_flag & O_EXCL)
+ nd.flags |= LOOKUP_EXCL;
+ }
+ if (open_flag & O_DIRECTORY)
+ nd.flags |= LOOKUP_DIRECTORY;
+ filp = do_last(&nd, &path, open_flag, acc_mode, mode, pathname);
+ while (unlikely(!filp)) { /* trailing symlink */
+ struct path holder;
+ struct inode *inode = path.dentry->d_inode;
+ void *cookie;
+ error = -ELOOP;
+ /* S_ISDIR part is a temporary automount kludge */
+ if ((open_flag & O_NOFOLLOW) && !S_ISDIR(inode->i_mode))
+ goto exit_dput;
+ if (count++ == 32)
+ goto exit_dput;
+ /*
+ * This is subtle. Instead of calling do_follow_link() we do
+ * the thing by hands. The reason is that this way we have zero
+ * link_count and path_walk() (called from ->follow_link)
+ * honoring LOOKUP_PARENT. After that we have the parent and
+ * last component, i.e. we are in the same situation as after
+ * the first path_walk(). Well, almost - if the last component
+ * is normal we get its copy stored in nd->last.name and we will
+ * have to putname() it when we are done. Procfs-like symlinks
+ * just set LAST_BIND.
+ */
+ nd.flags |= LOOKUP_PARENT;
+ error = security_inode_follow_link(path.dentry, &nd);
+ if (error)
+ goto exit_dput;
+ error = __do_follow_link(&path, &nd, &cookie);
+ if (unlikely(error)) {
+ /* nd.path had been dropped */
+ if (!IS_ERR(cookie) && inode->i_op->put_link)
+ inode->i_op->put_link(path.dentry, &nd, cookie);
+ path_put(&path);
+ release_open_intent(&nd);
+ filp = ERR_PTR(error);
+ goto out;
+ }
+ holder = path;
+ nd.flags &= ~LOOKUP_PARENT;
+ filp = do_last(&nd, &path, open_flag, acc_mode, mode, pathname);
+ if (inode->i_op->put_link)
+ inode->i_op->put_link(holder.dentry, &nd, cookie);
+ path_put(&holder);
}
- error = -ELOOP;
- if (count++==32) {
- __putname(nd.last.name);
- goto exit;
+out:
+ if (nd.root.mnt)
+ path_put(&nd.root);
+ if (filp == ERR_PTR(-ESTALE) && !force_reval) {
+ force_reval = 1;
+ goto reval;
}
- dir = nd.path.dentry;
- mutex_lock(&dir->d_inode->i_mutex);
- path.dentry = lookup_hash(&nd);
- path.mnt = nd.path.mnt;
- __putname(nd.last.name);
- goto do_last;
+ return filp;
+
+exit_dput:
+ path_put_conditional(&path, &nd);
+ if (!IS_ERR(nd.intent.open.file))
+ release_open_intent(&nd);
+exit_parent:
+ path_put(&nd.path);
+ filp = ERR_PTR(error);
+ goto out;
}
/**
if (error)
return error;
- vfs_dq_init(dir);
error = dir->i_op->mknod(dir, dentry, mode, dev);
if (!error)
fsnotify_create(dir, dentry);
if (error)
return error;
- vfs_dq_init(dir);
error = dir->i_op->mkdir(dir, dentry, mode);
if (!error)
fsnotify_mkdir(dir, dentry);
if (!dir->i_op->rmdir)
return -EPERM;
- vfs_dq_init(dir);
-
mutex_lock(&dentry->d_inode->i_mutex);
dentry_unhash(dentry);
if (d_mountpoint(dentry))
if (!dir->i_op->unlink)
return -EPERM;
- vfs_dq_init(dir);
-
mutex_lock(&dentry->d_inode->i_mutex);
if (d_mountpoint(dentry))
error = -EBUSY;
else {
error = security_inode_unlink(dir, dentry);
- if (!error)
+ if (!error) {
error = dir->i_op->unlink(dir, dentry);
+ if (!error)
+ dentry->d_inode->i_flags |= S_DEAD;
+ }
}
mutex_unlock(&dentry->d_inode->i_mutex);
if (error)
return error;
- vfs_dq_init(dir);
error = dir->i_op->symlink(dir, dentry, oldname);
if (!error)
fsnotify_create(dir, dentry);
return error;
mutex_lock(&inode->i_mutex);
- vfs_dq_init(dir);
error = dir->i_op->link(old_dentry, dir, new_dentry);
mutex_unlock(&inode->i_mutex);
if (!error)
* e) conversion from fhandle to dentry may come in the wrong moment - when
* we are removing the target. Solution: we will have to grab ->i_mutex
* in the fhandle_to_dentry code. [FIXME - current nfsfh.c relies on
- * ->i_mutex on parents, which works but leads to some truely excessive
+ * ->i_mutex on parents, which works but leads to some truly excessive
* locking].
*/
static int vfs_rename_dir(struct inode *old_dir, struct dentry *old_dentry,
else
error = old_dir->i_op->rename(old_dir, old_dentry, new_dir, new_dentry);
if (!error) {
+ if (target)
+ target->i_flags |= S_DEAD;
if (!(old_dir->i_sb->s_type->fs_flags & FS_RENAME_DOES_D_MOVE))
d_move(old_dentry, new_dentry);
}
if (!old_dir->i_op->rename)
return -EPERM;
- vfs_dq_init(old_dir);
- vfs_dq_init(new_dir);
-
old_name = fsnotify_oldname_init(old_dentry->d_name.name);
if (is_dir)
error = vfs_rename_dir(old_dir,old_dentry,new_dir,new_dentry);
else
error = vfs_rename_other(old_dir,old_dentry,new_dir,new_dentry);
- if (!error) {
- const char *new_name = old_dentry->d_name.name;
- fsnotify_move(old_dir, new_dir, old_name, new_name, is_dir,
+ if (!error)
+ fsnotify_move(old_dir, new_dir, old_name, is_dir,
new_dentry->d_inode, old_dentry);
- }
fsnotify_oldname_free(old_name);
return error;
Code Review / linux-2.6.git / blobdiff