if (!(nd->flags & LOOKUP_RCU)) {
touch_atime(&last->link);
cond_resched();
- } else if (atime_needs_update(&last->link, inode)) {
+ } else if (atime_needs_update_rcu(&last->link, inode)) {
if (unlikely(unlazy_walk(nd, NULL, 0)))
return ERR_PTR(-ECHILD);
touch_atime(&last->link);
if (error)
return error;
- if (!old_dir->i_op->rename && !old_dir->i_op->rename2)
+ if (!old_dir->i_op->rename)
return -EPERM;
- if (flags && !old_dir->i_op->rename2)
- return -EINVAL;
-
/*
* If we are going to change the parent - check write permissions,
* we'll need to flip '..'.
if (error)
goto out;
}
- if (!old_dir->i_op->rename2) {
- error = old_dir->i_op->rename(old_dir, old_dentry,
- new_dir, new_dentry);
- } else {
- WARN_ON(old_dir->i_op->rename != NULL);
- error = old_dir->i_op->rename2(old_dir, old_dentry,
- new_dir, new_dentry, flags);
- }
+ error = old_dir->i_op->rename(old_dir, old_dentry,
+ new_dir, new_dentry, flags);
if (error)
goto out;
}
EXPORT_SYMBOL(generic_readlink);
+ /**
+ * vfs_get_link - get symlink body
+ * @dentry: dentry on which to get symbolic link
+ * @done: caller needs to free returned data with this
+ *
+ * Calls security hook and i_op->get_link() on the supplied inode.
+ *
+ * It does not touch atime. That's up to the caller if necessary.
+ *
+ * Does not work on "special" symlinks like /proc/$$/fd/N
+ */
+ const char *vfs_get_link(struct dentry *dentry, struct delayed_call *done)
+ {
+ const char *res = ERR_PTR(-EINVAL);
+ struct inode *inode = d_inode(dentry);
+
+ if (d_is_symlink(dentry)) {
+ res = ERR_PTR(security_inode_readlink(dentry));
+ if (!res)
+ res = inode->i_op->get_link(dentry, inode, done);
+ }
+ return res;
+ }
+ EXPORT_SYMBOL(vfs_get_link);
+
/* get the link contents into pagecache */
const char *page_get_link(struct dentry *dentry, struct inode *inode,
struct delayed_call *callback)
ssize_t list_size, size, value_size = 0;
char *buf, *name, *value = NULL;
int uninitialized_var(error);
+ size_t slen;
- if (!old->d_inode->i_op->getxattr ||
- !new->d_inode->i_op->getxattr)
+ if (!(old->d_inode->i_opflags & IOP_XATTR) ||
+ !(new->d_inode->i_opflags & IOP_XATTR))
return 0;
list_size = vfs_listxattr(old, NULL, 0);
goto out;
}
- for (name = buf; name < (buf + list_size); name += strlen(name) + 1) {
+ for (name = buf; list_size; name += slen) {
+ slen = strnlen(name, list_size) + 1;
+
+ /* underlying fs providing us with an broken xattr list? */
+ if (WARN_ON(slen > list_size)) {
+ error = -EIO;
+ break;
+ }
+ list_size -= slen;
+
if (ovl_is_private_xattr(name))
continue;
retry:
goto retry;
}
+ error = security_inode_copy_up_xattr(name);
+ if (error < 0 && error != -EOPNOTSUPP)
+ break;
+ if (error == 1) {
+ error = 0;
+ continue; /* Discard */
+ }
error = vfs_setxattr(new, name, value, size, 0);
if (error)
break;
return error;
}
- static char *ovl_read_symlink(struct dentry *realdentry)
- {
- int res;
- char *buf;
- struct inode *inode = realdentry->d_inode;
- mm_segment_t old_fs;
-
- res = -EINVAL;
- if (!inode->i_op->readlink)
- goto err;
-
- res = -ENOMEM;
- buf = (char *) __get_free_page(GFP_KERNEL);
- if (!buf)
- goto err;
-
- old_fs = get_fs();
- set_fs(get_ds());
- /* The cast to a user pointer is valid due to the set_fs() */
- res = inode->i_op->readlink(realdentry,
- (char __user *)buf, PAGE_SIZE - 1);
- set_fs(old_fs);
- if (res < 0) {
- free_page((unsigned long) buf);
- goto err;
- }
- buf[res] = '\0';
-
- return buf;
-
- err:
- return ERR_PTR(res);
- }
-
static int ovl_set_timestamps(struct dentry *upperdentry, struct kstat *stat)
{
struct iattr attr = {
struct dentry *upper = NULL;
umode_t mode = stat->mode;
int err;
+ const struct cred *old_creds = NULL;
+ struct cred *new_creds = NULL;
newdentry = ovl_lookup_temp(workdir, dentry);
err = PTR_ERR(newdentry);
if (IS_ERR(upper))
goto out1;
+ err = security_inode_copy_up(dentry, &new_creds);
+ if (err < 0)
+ goto out2;
+
+ if (new_creds)
+ old_creds = override_creds(new_creds);
+
/* Can't properly set mode on creation because of the umask */
stat->mode &= S_IFMT;
err = ovl_create_real(wdir, newdentry, stat, link, NULL, true);
stat->mode = mode;
+
+ if (new_creds) {
+ revert_creds(old_creds);
+ put_cred(new_creds);
+ }
+
if (err)
goto out2;
int ovl_copy_up_one(struct dentry *parent, struct dentry *dentry,
struct path *lowerpath, struct kstat *stat)
{
+ DEFINE_DELAYED_CALL(done);
struct dentry *workdir = ovl_workdir(dentry);
int err;
struct kstat pstat;
struct path parentpath;
+ struct dentry *lowerdentry = lowerpath->dentry;
struct dentry *upperdir;
struct dentry *upperdentry;
- const struct cred *old_cred;
- char *link = NULL;
+ const char *link = NULL;
if (WARN_ON(!workdir))
return -EROFS;
- ovl_do_check_copy_up(lowerpath->dentry);
+ ovl_do_check_copy_up(lowerdentry);
ovl_path_upper(parent, &parentpath);
upperdir = parentpath.dentry;
return err;
if (S_ISLNK(stat->mode)) {
- link = ovl_read_symlink(lowerpath->dentry);
+ link = vfs_get_link(lowerdentry, &done);
if (IS_ERR(link))
return PTR_ERR(link);
}
- old_cred = ovl_override_creds(dentry->d_sb);
-
err = -EIO;
if (lock_rename(workdir, upperdir) != NULL) {
pr_err("overlayfs: failed to lock workdir+upperdir\n");
}
out_unlock:
unlock_rename(workdir, upperdir);
- revert_creds(old_cred);
-
- if (link)
- free_page((unsigned long) link);
+ do_delayed_call(&done);
return err;
}
int ovl_copy_up(struct dentry *dentry)
{
- int err;
+ int err = 0;
+ const struct cred *old_cred = ovl_override_creds(dentry->d_sb);
- err = 0;
while (!err) {
struct dentry *next;
struct dentry *parent;
dput(parent);
dput(next);
}
+ revert_creds(old_cred);
return err;
}
#include <linux/cred.h>
#include <linux/posix_acl.h>
#include <linux/posix_acl_xattr.h>
+ #include <linux/atomic.h>
#include "overlayfs.h"
void ovl_cleanup(struct inode *wdir, struct dentry *wdentry)
{
struct dentry *temp;
char name[20];
+ static atomic_t temp_id = ATOMIC_INIT(0);
- snprintf(name, sizeof(name), "#%lx", (unsigned long) dentry);
+ /* counter is allowed to wrap, since temp dentries are ephemeral */
+ snprintf(name, sizeof(name), "#%x", atomic_inc_return(&temp_id));
temp = lookup_one_len(name, workdir, strlen(name));
if (!IS_ERR(temp) && temp->d_inode) {
if (override_cred) {
override_cred->fsuid = inode->i_uid;
override_cred->fsgid = inode->i_gid;
+ if (!hardlink) {
+ err = security_dentry_create_files_as(dentry,
+ stat->mode, &dentry->d_name, old_cred,
+ override_cred);
+ if (err) {
+ put_cred(override_cred);
+ goto out_revert_creds;
+ }
+ }
put_cred(override_creds(override_cred));
put_cred(override_cred);
err = ovl_create_over_whiteout(dentry, inode, stat,
link, hardlink);
}
+out_revert_creds:
revert_creds(old_cred);
if (!err) {
struct inode *realinode = d_inode(ovl_dentry_upper(dentry));
.symlink = ovl_symlink,
.unlink = ovl_unlink,
.rmdir = ovl_rmdir,
- .rename2 = ovl_rename2,
+ .rename = ovl_rename2,
.link = ovl_link,
.setattr = ovl_setattr,
.create = ovl_create,
.mknod = ovl_mknod,
.permission = ovl_permission,
.getattr = ovl_dir_getattr,
- .setxattr = generic_setxattr,
- .getxattr = generic_getxattr,
.listxattr = ovl_listxattr,
- .removexattr = generic_removexattr,
.get_acl = ovl_get_acl,
.update_time = ovl_update_time,
};
struct dentry *parent;
struct kstat stat;
struct path lowerpath;
+ const struct cred *old_cred;
parent = dget_parent(dentry);
err = ovl_copy_up(parent);
goto out_dput_parent;
ovl_path_lower(dentry, &lowerpath);
- err = vfs_getattr(&lowerpath, &stat);
- if (err)
- goto out_dput_parent;
- stat.size = 0;
- err = ovl_copy_up_one(parent, dentry, &lowerpath, &stat);
+ old_cred = ovl_override_creds(dentry->d_sb);
+ err = vfs_getattr(&lowerpath, &stat);
+ if (!err) {
+ stat.size = 0;
+ err = ovl_copy_up_one(parent, dentry, &lowerpath, &stat);
+ }
+ revert_creds(old_cred);
out_dput_parent:
dput(parent);
* inode_newsize_ok() will always check against MAX_LFS_FILESIZE and not
* check for a swapfile (which this won't be anyway).
*/
- err = inode_change_ok(dentry->d_inode, attr);
+ err = setattr_prepare(dentry, attr);
if (err)
return err;
struct inode *inode,
struct delayed_call *done)
{
- struct dentry *realdentry;
- struct inode *realinode;
const struct cred *old_cred;
const char *p;
if (!dentry)
return ERR_PTR(-ECHILD);
- realdentry = ovl_dentry_real(dentry);
- realinode = realdentry->d_inode;
-
- if (WARN_ON(!realinode->i_op->get_link))
- return ERR_PTR(-EPERM);
-
old_cred = ovl_override_creds(dentry->d_sb);
- p = realinode->i_op->get_link(realdentry, realinode, done);
+ p = vfs_get_link(ovl_dentry_real(dentry), done);
revert_creds(old_cred);
return p;
}
- static int ovl_readlink(struct dentry *dentry, char __user *buf, int bufsiz)
- {
- struct path realpath;
- struct inode *realinode;
- const struct cred *old_cred;
- int err;
-
- ovl_path_real(dentry, &realpath);
- realinode = realpath.dentry->d_inode;
-
- if (!realinode->i_op->readlink)
- return -EINVAL;
-
- old_cred = ovl_override_creds(dentry->d_sb);
- err = realinode->i_op->readlink(realpath.dentry, buf, bufsiz);
- revert_creds(old_cred);
- return err;
- }
-
bool ovl_is_private_xattr(const char *name)
{
return strncmp(name, OVL_XATTR_PREFIX,
.setattr = ovl_setattr,
.permission = ovl_permission,
.getattr = ovl_getattr,
- .setxattr = generic_setxattr,
- .getxattr = generic_getxattr,
.listxattr = ovl_listxattr,
- .removexattr = generic_removexattr,
.get_acl = ovl_get_acl,
.update_time = ovl_update_time,
};
static const struct inode_operations ovl_symlink_inode_operations = {
.setattr = ovl_setattr,
.get_link = ovl_get_link,
- .readlink = ovl_readlink,
+ .readlink = generic_readlink,
.getattr = ovl_getattr,
- .setxattr = generic_setxattr,
- .getxattr = generic_getxattr,
.listxattr = ovl_listxattr,
- .removexattr = generic_removexattr,
.update_time = ovl_update_time,
};
{
int res;
char val;
- struct inode *inode = dentry->d_inode;
- if (!S_ISDIR(inode->i_mode) || !(inode->i_opflags & IOP_XATTR))
+ if (!d_is_dir(dentry))
return false;
- res = __vfs_getxattr(dentry, inode, OVL_XATTR_OPAQUE, &val, 1);
+ res = vfs_getxattr(dentry, OVL_XATTR_OPAQUE, &val, 1);
if (res == 1 && val == 'y')
return true;
DCACHE_OP_COMPARE);
}
- static inline struct dentry *ovl_lookup_real(struct super_block *ovl_sb,
- struct dentry *dir,
+ static inline struct dentry *ovl_lookup_real(struct dentry *dir,
const struct qstr *name)
{
- const struct cred *old_cred;
struct dentry *dentry;
- old_cred = ovl_override_creds(ovl_sb);
dentry = lookup_one_len_unlocked(name->name, dir, name->len);
- revert_creds(old_cred);
if (IS_ERR(dentry)) {
if (PTR_ERR(dentry) == -ENOENT)
unsigned int flags)
{
struct ovl_entry *oe;
+ const struct cred *old_cred;
struct ovl_entry *poe = dentry->d_parent->d_fsdata;
struct path *stack = NULL;
struct dentry *upperdir, *upperdentry = NULL;
unsigned int i;
int err;
+ old_cred = ovl_override_creds(dentry->d_sb);
upperdir = ovl_upperdentry_dereference(poe);
if (upperdir) {
- this = ovl_lookup_real(dentry->d_sb, upperdir, &dentry->d_name);
+ this = ovl_lookup_real(upperdir, &dentry->d_name);
err = PTR_ERR(this);
if (IS_ERR(this))
goto out;
bool opaque = false;
struct path lowerpath = poe->lowerstack[i];
- this = ovl_lookup_real(dentry->d_sb,
- lowerpath.dentry, &dentry->d_name);
+ this = ovl_lookup_real(lowerpath.dentry, &dentry->d_name);
err = PTR_ERR(this);
if (IS_ERR(this)) {
/*
ovl_copyattr(realdentry->d_inode, inode);
}
+ revert_creds(old_cred);
oe->opaque = upperopaque;
oe->__upperdentry = upperdentry;
memcpy(oe->lowerstack, stack, sizeof(struct path) * ctr);
out_put_upper:
dput(upperdentry);
out:
+ revert_creds(old_cred);
return ERR_PTR(err);
}
if (err)
goto out_dput;
+ /*
+ * Try to remove POSIX ACL xattrs from workdir. We are good if:
+ *
+ * a) success (there was a POSIX ACL xattr and was removed)
+ * b) -ENODATA (there was no POSIX ACL xattr)
+ * c) -EOPNOTSUPP (POSIX ACL xattrs are not supported)
+ *
+ * There are various other error values that could effectively
+ * mean that the xattr doesn't exist (e.g. -ERANGE is returned
+ * if the xattr name is too long), but the set of filesystems
+ * allowed as upper are limited to "normal" ones, where checking
+ * for the above two errors is sufficient.
+ */
err = vfs_removexattr(work, XATTR_NAME_POSIX_ACL_DEFAULT);
if (err && err != -ENODATA && err != -EOPNOTSUPP)
goto out_dput;
sb->s_xattr = ovl_xattr_handlers;
sb->s_root = root_dentry;
sb->s_fs_info = ufs;
- sb->s_flags |= MS_POSIXACL;
+ sb->s_flags |= MS_POSIXACL | MS_NOREMOTELOCK;
return 0;
extern struct files_stat_struct files_stat;
extern unsigned long get_max_files(void);
-extern int sysctl_nr_open;
+extern unsigned int sysctl_nr_open;
extern struct inodes_stat_t inodes_stat;
extern int leases_enable, lease_break_time;
extern int sysctl_protected_symlinks;
#define ATTR_KILL_PRIV (1 << 14)
#define ATTR_OPEN (1 << 15) /* Truncating from open(O_TRUNC) */
#define ATTR_TIMES_SET (1 << 16)
+#define ATTR_TOUCH (1 << 17)
/*
* Whiteout is represented by a char device. The following constants define the
unsigned long nrexceptional;
pgoff_t writeback_index;/* writeback starts here */
const struct address_space_operations *a_ops; /* methods */
- unsigned long flags; /* error bits/gfp mask */
+ unsigned long flags; /* error bits */
spinlock_t private_lock; /* for use by the address_space */
+ gfp_t gfp_mask; /* implicit gfp mask for allocations */
struct list_head private_list; /* ditto */
void *private_data; /* ditto */
} __attribute__((aligned(sizeof(long))));
#define IOP_FASTPERM 0x0001
#define IOP_LOOKUP 0x0002
#define IOP_NOFOLLOW 0x0004
+#define IOP_XATTR 0x0008
/*
* Keep mostly read-only and often accessed (especially for
extern void send_sigio(struct fown_struct *fown, int fd, int band);
+/*
+ * Return the inode to use for locking
+ *
+ * For overlayfs this should be the overlay inode, not the real inode returned
+ * by file_inode(). For any other fs file_inode(filp) and locks_inode(filp) are
+ * equal.
+ */
+static inline struct inode *locks_inode(const struct file *f)
+{
+ return f->f_path.dentry->d_inode;
+}
+
#ifdef CONFIG_FILE_LOCKING
extern int fcntl_getlk(struct file *, unsigned int, struct flock __user *);
extern int fcntl_setlk(unsigned int, struct file *, unsigned int,
static inline int locks_lock_file_wait(struct file *filp, struct file_lock *fl)
{
- return locks_lock_inode_wait(file_inode(filp), fl);
+ return locks_lock_inode_wait(locks_inode(filp), fl);
}
struct fasync_struct {
}
extern struct timespec current_fs_time(struct super_block *sb);
+extern struct timespec current_time(struct inode *inode);
/*
* Snapshotting support.
int (*rmdir) (struct inode *,struct dentry *);
int (*mknod) (struct inode *,struct dentry *,umode_t,dev_t);
int (*rename) (struct inode *, struct dentry *,
- struct inode *, struct dentry *);
- int (*rename2) (struct inode *, struct dentry *,
struct inode *, struct dentry *, unsigned int);
int (*setattr) (struct dentry *, struct iattr *);
int (*getattr) (struct vfsmount *mnt, struct dentry *, struct kstat *);
- int (*setxattr) (struct dentry *, struct inode *,
- const char *, const void *, size_t, int);
- ssize_t (*getxattr) (struct dentry *, struct inode *,
- const char *, void *, size_t);
ssize_t (*listxattr) (struct dentry *, char *, size_t);
- int (*removexattr) (struct dentry *, const char *);
int (*fiemap)(struct inode *, struct fiemap_extent_info *, u64 start,
u64 len);
int (*update_time)(struct inode *, struct timespec *, int);
S_VERSION = 8,
};
-extern bool atime_needs_update(const struct path *, struct inode *);
extern void touch_atime(const struct path *);
static inline void file_accessed(struct file *file)
{
int (*test)(struct super_block *,void *),
int (*set)(struct super_block *,void *),
int flags, void *data);
-extern struct dentry *mount_pseudo(struct file_system_type *, char *,
- const struct super_operations *ops,
- const struct dentry_operations *dops,
- unsigned long);
+extern struct dentry *mount_pseudo_xattr(struct file_system_type *, char *,
+ const struct super_operations *ops,
+ const struct xattr_handler **xattr,
+ const struct dentry_operations *dops,
+ unsigned long);
+
+static inline struct dentry *
+mount_pseudo(struct file_system_type *fs_type, char *name,
+ const struct super_operations *ops,
+ const struct dentry_operations *dops, unsigned long magic)
+{
+ return mount_pseudo_xattr(fs_type, name, ops, NULL, dops, magic);
+}
/* Alas, no aliases. Too much hassle with bringing module.h everywhere */
#define fops_get(fops) \
static inline int locks_verify_locked(struct file *file)
{
- if (mandatory_lock(file_inode(file)))
+ if (mandatory_lock(locks_inode(file)))
return locks_mandatory_locked(file);
return 0;
}
/* fs/splice.c */
extern ssize_t generic_file_splice_read(struct file *, loff_t *,
struct pipe_inode_info *, size_t, unsigned int);
-extern ssize_t default_file_splice_read(struct file *, loff_t *,
- struct pipe_inode_info *, size_t, unsigned int);
extern ssize_t iter_file_splice_write(struct pipe_inode_info *,
struct file *, loff_t *, size_t, unsigned int);
extern ssize_t generic_splice_sendpage(struct pipe_inode_info *pipe,
extern int vfs_lstat(const char __user *, struct kstat *);
extern int vfs_fstat(unsigned int, struct kstat *);
extern int vfs_fstatat(int , const char __user *, struct kstat *, int);
+ extern const char *vfs_get_link(struct dentry *, struct delayed_call *);
extern int __generic_block_fiemap(struct inode *inode,
struct fiemap_extent_info *fieinfo,
extern int simple_link(struct dentry *, struct inode *, struct dentry *);
extern int simple_unlink(struct inode *, struct dentry *);
extern int simple_rmdir(struct inode *, struct dentry *);
-extern int simple_rename(struct inode *, struct dentry *, struct inode *, struct dentry *);
+extern int simple_rename(struct inode *, struct dentry *,
+ struct inode *, struct dentry *, unsigned int);
extern int noop_fsync(struct file *, loff_t, loff_t, int);
extern int simple_empty(struct dentry *);
extern int simple_readpage(struct file *file, struct page *page);
#define buffer_migrate_page NULL
#endif
-extern int inode_change_ok(const struct inode *, struct iattr *);
+extern int setattr_prepare(struct dentry *, struct iattr *);
extern int inode_newsize_ok(const struct inode *, loff_t offset);
extern void setattr_copy(struct inode *inode, const struct iattr *attr);
projects / cascardo / linux.git / commitdiff