diff --git a/drivers/base/devtmpfs.c b/drivers/base/devtmpfs.c index 2e0c3cdb4184..653c8c6ac7a7 100644 --- a/drivers/base/devtmpfs.c +++ b/drivers/base/devtmpfs.c @@ -162,7 +162,7 @@ static int dev_mkdir(const char *name, umode_t mode) if (IS_ERR(dentry)) return PTR_ERR(dentry); - err = vfs_mkdir(d_inode(path.dentry), dentry, mode); + err = vfs_mkdir(&init_user_ns, d_inode(path.dentry), dentry, mode); if (!err) /* mark as kernel-created inode */ d_inode(dentry)->i_private = &thread; @@ -212,7 +212,8 @@ static int handle_create(const char *nodename, umode_t mode, kuid_t uid, if (IS_ERR(dentry)) return PTR_ERR(dentry); - err = vfs_mknod(d_inode(path.dentry), dentry, mode, dev->devt); + err = vfs_mknod(&init_user_ns, d_inode(path.dentry), dentry, mode, + dev->devt); if (!err) { struct iattr newattrs; @@ -242,7 +243,8 @@ static int dev_rmdir(const char *name) return PTR_ERR(dentry); if (d_really_is_positive(dentry)) { if (d_inode(dentry)->i_private == &thread) - err = vfs_rmdir(d_inode(parent.dentry), dentry); + err = vfs_rmdir(&init_user_ns, d_inode(parent.dentry), + dentry); else err = -EPERM; } else { @@ -330,7 +332,8 @@ static int handle_remove(const char *nodename, struct device *dev) inode_lock(d_inode(dentry)); notify_change(&init_user_ns, dentry, &newattrs, NULL); inode_unlock(d_inode(dentry)); - err = vfs_unlink(d_inode(parent.dentry), dentry, NULL); + err = vfs_unlink(&init_user_ns, d_inode(parent.dentry), + dentry, NULL); if (!err || err == -ENOENT) deleted = 1; } diff --git a/fs/cachefiles/namei.c b/fs/cachefiles/namei.c index 7b987de0babe..7bf0732ae25c 100644 --- a/fs/cachefiles/namei.c +++ b/fs/cachefiles/namei.c @@ -311,7 +311,8 @@ static int cachefiles_bury_object(struct cachefiles_cache *cache, cachefiles_io_error(cache, "Unlink security error"); } else { trace_cachefiles_unlink(object, rep, why); - ret = vfs_unlink(d_inode(dir), rep, NULL); + ret = vfs_unlink(&init_user_ns, d_inode(dir), rep, + NULL); if (preemptive) cachefiles_mark_object_buried(cache, rep, why); @@ -413,8 +414,10 @@ static int cachefiles_bury_object(struct cachefiles_cache *cache, cachefiles_io_error(cache, "Rename security error %d", ret); } else { struct renamedata rd = { + .old_mnt_userns = &init_user_ns, .old_dir = d_inode(dir), .old_dentry = rep, + .new_mnt_userns = &init_user_ns, .new_dir = d_inode(cache->graveyard), .new_dentry = grave, }; @@ -566,7 +569,7 @@ int cachefiles_walk_to_object(struct cachefiles_object *parent, if (ret < 0) goto create_error; start = jiffies; - ret = vfs_mkdir(d_inode(dir), next, 0); + ret = vfs_mkdir(&init_user_ns, d_inode(dir), next, 0); cachefiles_hist(cachefiles_mkdir_histogram, start); if (!key) trace_cachefiles_mkdir(object, next, ret); @@ -602,7 +605,8 @@ int cachefiles_walk_to_object(struct cachefiles_object *parent, if (ret < 0) goto create_error; start = jiffies; - ret = vfs_create(d_inode(dir), next, S_IFREG, true); + ret = vfs_create(&init_user_ns, d_inode(dir), next, + S_IFREG, true); cachefiles_hist(cachefiles_create_histogram, start); trace_cachefiles_create(object, next, ret); if (ret < 0) @@ -796,7 +800,7 @@ struct dentry *cachefiles_get_directory(struct cachefiles_cache *cache, ret = security_path_mkdir(&path, subdir, 0700); if (ret < 0) goto mkdir_error; - ret = vfs_mkdir(d_inode(dir), subdir, 0700); + ret = vfs_mkdir(&init_user_ns, d_inode(dir), subdir, 0700); if (ret < 0) goto mkdir_error; diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c index ff48abb09679..73e3d47e7b2d 100644 --- a/fs/ecryptfs/inode.c +++ b/fs/ecryptfs/inode.c @@ -141,7 +141,8 @@ static int ecryptfs_do_unlink(struct inode *dir, struct dentry *dentry, else if (d_unhashed(lower_dentry)) rc = -EINVAL; else - rc = vfs_unlink(lower_dir_inode, lower_dentry, NULL); + rc = vfs_unlink(&init_user_ns, lower_dir_inode, lower_dentry, + NULL); if (rc) { printk(KERN_ERR "Error in vfs_unlink; rc = [%d]\n", rc); goto out_unlock; @@ -180,7 +181,8 @@ ecryptfs_do_create(struct inode *directory_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 = vfs_create(&init_user_ns, d_inode(lower_dir_dentry), lower_dentry, + mode, true); if (rc) { printk(KERN_ERR "%s: Failure to create dentry in lower fs; " "rc = [%d]\n", __func__, rc); @@ -190,7 +192,8 @@ 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, d_inode(lower_dir_dentry), + lower_dentry, NULL); goto out_lock; } fsstack_copy_attr_times(directory_inode, d_inode(lower_dir_dentry)); @@ -436,8 +439,8 @@ static int ecryptfs_link(struct dentry *old_dentry, struct inode *dir, 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 = vfs_link(lower_old_dentry, &init_user_ns, + d_inode(lower_dir_dentry), 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); @@ -481,7 +484,7 @@ 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, d_inode(lower_dir_dentry), lower_dentry, encoded_symname); kfree(encoded_symname); if (rc || d_really_is_negative(lower_dentry)) @@ -507,7 +510,8 @@ static int ecryptfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode 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 = vfs_mkdir(&init_user_ns, d_inode(lower_dir_dentry), lower_dentry, + mode); if (rc || d_really_is_negative(lower_dentry)) goto out; rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb); @@ -541,7 +545,7 @@ static int ecryptfs_rmdir(struct inode *dir, struct dentry *dentry) else if (d_unhashed(lower_dentry)) rc = -EINVAL; else - rc = vfs_rmdir(lower_dir_inode, lower_dentry); + rc = vfs_rmdir(&init_user_ns, lower_dir_inode, lower_dentry); if (!rc) { clear_nlink(d_inode(dentry)); fsstack_copy_attr_times(dir, lower_dir_inode); @@ -563,7 +567,8 @@ ecryptfs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev 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 = vfs_mknod(&init_user_ns, d_inode(lower_dir_dentry), lower_dentry, + mode, dev); if (rc || d_really_is_negative(lower_dentry)) goto out; rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb); @@ -621,10 +626,12 @@ ecryptfs_rename(struct inode *old_dir, struct dentry *old_dentry, goto out_lock; } - rd.old_dir = d_inode(lower_old_dir_dentry); - rd.old_dentry = lower_old_dentry; - rd.new_dir = d_inode(lower_new_dir_dentry); - rd.new_dentry = lower_new_dentry; + 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; diff --git a/fs/init.c b/fs/init.c index 891284f8a443..e65452750fa5 100644 --- a/fs/init.c +++ b/fs/init.c @@ -157,8 +157,8 @@ int __init init_mknod(const char *filename, umode_t mode, unsigned int dev) mode &= ~current_umask(); error = security_path_mknod(&path, dentry, mode, dev); if (!error) - error = vfs_mknod(path.dentry->d_inode, dentry, mode, - new_decode_dev(dev)); + error = vfs_mknod(&init_user_ns, path.dentry->d_inode, dentry, + mode, new_decode_dev(dev)); done_path_create(&path, dentry); return error; } @@ -187,8 +187,8 @@ int __init init_link(const char *oldname, const char *newname) error = security_path_link(old_path.dentry, &new_path, new_dentry); if (error) goto out_dput; - error = vfs_link(old_path.dentry, new_path.dentry->d_inode, new_dentry, - NULL); + error = vfs_link(old_path.dentry, &init_user_ns, + new_path.dentry->d_inode, new_dentry, NULL); out_dput: done_path_create(&new_path, new_dentry); out: @@ -207,7 +207,8 @@ int __init init_symlink(const char *oldname, const char *newname) return PTR_ERR(dentry); error = security_path_symlink(&path, dentry, oldname); if (!error) - error = vfs_symlink(path.dentry->d_inode, dentry, oldname); + error = vfs_symlink(&init_user_ns, path.dentry->d_inode, dentry, + oldname); done_path_create(&path, dentry); return error; } @@ -230,7 +231,8 @@ int __init init_mkdir(const char *pathname, umode_t mode) mode &= ~current_umask(); error = security_path_mkdir(&path, dentry, mode); if (!error) - error = vfs_mkdir(path.dentry->d_inode, dentry, mode); + error = vfs_mkdir(&init_user_ns, path.dentry->d_inode, dentry, + mode); done_path_create(&path, dentry); return error; } diff --git a/fs/namei.c b/fs/namei.c index 38ab51881247..5c9f6f8e90c4 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -2874,10 +2874,26 @@ void unlock_rename(struct dentry *p1, struct dentry *p2) } EXPORT_SYMBOL(unlock_rename); -int vfs_create(struct inode *dir, struct dentry *dentry, umode_t mode, - bool want_excl) +/** + * vfs_create - create new file + * @mnt_userns: user namespace of the mount the inode was found from + * @dir: inode of @dentry + * @dentry: pointer to dentry of the base directory + * @mode: mode of the new file + * @want_excl: whether the file must not yet exist + * + * Create a new file. + * + * If the inode has been found through an idmapped mount the user namespace of + * the vfsmount must be passed through @mnt_userns. This function will then take + * care to map the inode according to @mnt_userns before checking permissions. + * On non-idmapped mounts or if permission checking is to be performed on the + * raw inode simply passs init_user_ns. + */ +int vfs_create(struct user_namespace *mnt_userns, struct inode *dir, + struct dentry *dentry, umode_t mode, bool want_excl) { - int error = may_create(&init_user_ns, dir, dentry); + int error = may_create(mnt_userns, dir, dentry); if (error) return error; @@ -3353,7 +3369,23 @@ static int do_open(struct nameidata *nd, return error; } -struct dentry *vfs_tmpfile(struct dentry *dentry, umode_t mode, int open_flag) +/** + * vfs_tmpfile - create tmpfile + * @mnt_userns: user namespace of the mount the inode was found from + * @dentry: pointer to dentry of the base directory + * @mode: mode of the new tmpfile + * @open_flags: flags + * + * Create a temporary file. + * + * If the inode has been found through an idmapped mount the user namespace of + * the vfsmount must be passed through @mnt_userns. This function will then take + * care to map the inode according to @mnt_userns before checking permissions. + * On non-idmapped mounts or if permission checking is to be performed on the + * raw inode simply passs init_user_ns. + */ +struct dentry *vfs_tmpfile(struct user_namespace *mnt_userns, + struct dentry *dentry, umode_t mode, int open_flag) { struct dentry *child = NULL; struct inode *dir = dentry->d_inode; @@ -3361,7 +3393,7 @@ struct dentry *vfs_tmpfile(struct dentry *dentry, umode_t mode, int open_flag) int error; /* we want directory to be writable */ - error = inode_permission(&init_user_ns, dir, MAY_WRITE | MAY_EXEC); + error = inode_permission(mnt_userns, dir, MAY_WRITE | MAY_EXEC); if (error) goto out_err; error = -EOPNOTSUPP; @@ -3396,6 +3428,7 @@ static int do_tmpfile(struct nameidata *nd, unsigned flags, const struct open_flags *op, struct file *file) { + struct user_namespace *mnt_userns; struct dentry *child; struct path path; int error = path_lookupat(nd, flags | LOOKUP_DIRECTORY, &path); @@ -3404,7 +3437,8 @@ static int do_tmpfile(struct nameidata *nd, unsigned flags, error = mnt_want_write(path.mnt); if (unlikely(error)) goto out; - child = vfs_tmpfile(path.dentry, op->mode, op->open_flag); + mnt_userns = mnt_user_ns(path.mnt); + child = vfs_tmpfile(mnt_userns, path.dentry, op->mode, op->open_flag); error = PTR_ERR(child); if (IS_ERR(child)) goto out2; @@ -3616,10 +3650,27 @@ inline struct dentry *user_path_create(int dfd, const char __user *pathname, } EXPORT_SYMBOL(user_path_create); -int vfs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev) +/** + * vfs_mknod - create device node or file + * @mnt_userns: user namespace of the mount the inode was found from + * @dir: inode of @dentry + * @dentry: pointer to dentry of the base directory + * @mode: mode of the new device node or file + * @dev: device number of device to create + * + * Create a device node or file. + * + * If the inode has been found through an idmapped mount the user namespace of + * the vfsmount must be passed through @mnt_userns. This function will then take + * care to map the inode according to @mnt_userns before checking permissions. + * On non-idmapped mounts or if permission checking is to be performed on the + * raw inode simply passs init_user_ns. + */ +int vfs_mknod(struct user_namespace *mnt_userns, struct inode *dir, + struct dentry *dentry, umode_t mode, dev_t dev) { bool is_whiteout = S_ISCHR(mode) && dev == WHITEOUT_DEV; - int error = may_create(&init_user_ns, dir, dentry); + int error = may_create(mnt_userns, dir, dentry); if (error) return error; @@ -3666,6 +3717,7 @@ static int may_mknod(umode_t mode) static long do_mknodat(int dfd, const char __user *filename, umode_t mode, unsigned int dev) { + struct user_namespace *mnt_userns; struct dentry *dentry; struct path path; int error; @@ -3684,18 +3736,22 @@ static long do_mknodat(int dfd, const char __user *filename, umode_t mode, error = security_path_mknod(&path, dentry, mode, dev); if (error) goto out; + + mnt_userns = mnt_user_ns(path.mnt); switch (mode & S_IFMT) { case 0: case S_IFREG: - error = vfs_create(path.dentry->d_inode,dentry,mode,true); + error = vfs_create(mnt_userns, path.dentry->d_inode, + dentry, mode, true); if (!error) ima_post_path_mknod(dentry); break; case S_IFCHR: case S_IFBLK: - error = vfs_mknod(path.dentry->d_inode,dentry,mode, - new_decode_dev(dev)); + error = vfs_mknod(mnt_userns, path.dentry->d_inode, + dentry, mode, new_decode_dev(dev)); break; case S_IFIFO: case S_IFSOCK: - error = vfs_mknod(path.dentry->d_inode,dentry,mode,0); + error = vfs_mknod(mnt_userns, path.dentry->d_inode, + dentry, mode, 0); break; } out: @@ -3718,9 +3774,25 @@ SYSCALL_DEFINE3(mknod, const char __user *, filename, umode_t, mode, unsigned, d return do_mknodat(AT_FDCWD, filename, mode, dev); } -int vfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) +/** + * vfs_mkdir - create directory + * @mnt_userns: user namespace of the mount the inode was found from + * @dir: inode of @dentry + * @dentry: pointer to dentry of the base directory + * @mode: mode of the new directory + * + * Create a directory. + * + * If the inode has been found through an idmapped mount the user namespace of + * the vfsmount must be passed through @mnt_userns. This function will then take + * care to map the inode according to @mnt_userns before checking permissions. + * On non-idmapped mounts or if permission checking is to be performed on the + * raw inode simply passs init_user_ns. + */ +int vfs_mkdir(struct user_namespace *mnt_userns, struct inode *dir, + struct dentry *dentry, umode_t mode) { - int error = may_create(&init_user_ns, dir, dentry); + int error = may_create(mnt_userns, dir, dentry); unsigned max_links = dir->i_sb->s_max_links; if (error) @@ -3759,8 +3831,11 @@ static long do_mkdirat(int dfd, const char __user *pathname, umode_t mode) if (!IS_POSIXACL(path.dentry->d_inode)) mode &= ~current_umask(); error = security_path_mkdir(&path, dentry, mode); - if (!error) - error = vfs_mkdir(path.dentry->d_inode, dentry, mode); + if (!error) { + struct user_namespace *mnt_userns; + mnt_userns = mnt_user_ns(path.mnt); + error = vfs_mkdir(mnt_userns, path.dentry->d_inode, dentry, mode); + } done_path_create(&path, dentry); if (retry_estale(error, lookup_flags)) { lookup_flags |= LOOKUP_REVAL; @@ -3779,9 +3854,24 @@ SYSCALL_DEFINE2(mkdir, const char __user *, pathname, umode_t, mode) return do_mkdirat(AT_FDCWD, pathname, mode); } -int vfs_rmdir(struct inode *dir, struct dentry *dentry) +/** + * vfs_rmdir - remove directory + * @mnt_userns: user namespace of the mount the inode was found from + * @dir: inode of @dentry + * @dentry: pointer to dentry of the base directory + * + * Remove a directory. + * + * If the inode has been found through an idmapped mount the user namespace of + * the vfsmount must be passed through @mnt_userns. This function will then take + * care to map the inode according to @mnt_userns before checking permissions. + * On non-idmapped mounts or if permission checking is to be performed on the + * raw inode simply passs init_user_ns. + */ +int vfs_rmdir(struct user_namespace *mnt_userns, struct inode *dir, + struct dentry *dentry) { - int error = may_delete(&init_user_ns, dir, dentry, 1); + int error = may_delete(mnt_userns, dir, dentry, 1); if (error) return error; @@ -3821,6 +3911,7 @@ EXPORT_SYMBOL(vfs_rmdir); long do_rmdir(int dfd, struct filename *name) { + struct user_namespace *mnt_userns; int error = 0; struct dentry *dentry; struct path path; @@ -3861,7 +3952,8 @@ long do_rmdir(int dfd, struct filename *name) error = security_path_rmdir(&path, dentry); if (error) goto exit3; - error = vfs_rmdir(path.dentry->d_inode, dentry); + mnt_userns = mnt_user_ns(path.mnt); + error = vfs_rmdir(mnt_userns, path.dentry->d_inode, dentry); exit3: dput(dentry); exit2: @@ -3884,6 +3976,7 @@ SYSCALL_DEFINE1(rmdir, const char __user *, pathname) /** * vfs_unlink - unlink a filesystem object + * @mnt_userns: user namespace of the mount the inode was found from * @dir: parent directory * @dentry: victim * @delegated_inode: returns victim inode, if the inode is delegated. @@ -3899,11 +3992,18 @@ SYSCALL_DEFINE1(rmdir, const char __user *, pathname) * Alternatively, a caller may pass NULL for delegated_inode. This may * be appropriate for callers that expect the underlying filesystem not * to be NFS exported. + * + * If the inode has been found through an idmapped mount the user namespace of + * the vfsmount must be passed through @mnt_userns. This function will then take + * care to map the inode according to @mnt_userns before checking permissions. + * On non-idmapped mounts or if permission checking is to be performed on the + * raw inode simply passs init_user_ns. */ -int vfs_unlink(struct inode *dir, struct dentry *dentry, struct inode **delegated_inode) +int vfs_unlink(struct user_namespace *mnt_userns, struct inode *dir, + struct dentry *dentry, struct inode **delegated_inode) { struct inode *target = dentry->d_inode; - int error = may_delete(&init_user_ns, dir, dentry, 0); + int error = may_delete(mnt_userns, dir, dentry, 0); if (error) return error; @@ -3974,6 +4074,8 @@ long do_unlinkat(int dfd, struct filename *name) dentry = __lookup_hash(&last, path.dentry, lookup_flags); error = PTR_ERR(dentry); if (!IS_ERR(dentry)) { + struct user_namespace *mnt_userns; + /* Why not before? Because we want correct error value */ if (last.name[last.len]) goto slashes; @@ -3984,7 +4086,8 @@ long do_unlinkat(int dfd, struct filename *name) error = security_path_unlink(&path, dentry); if (error) goto exit2; - error = vfs_unlink(path.dentry->d_inode, dentry, &delegated_inode); + mnt_userns = mnt_user_ns(path.mnt); + error = vfs_unlink(mnt_userns, path.dentry->d_inode, dentry, &delegated_inode); exit2: dput(dentry); } @@ -4033,9 +4136,25 @@ SYSCALL_DEFINE1(unlink, const char __user *, pathname) return do_unlinkat(AT_FDCWD, getname(pathname)); } -int vfs_symlink(struct inode *dir, struct dentry *dentry, const char *oldname) +/** + * vfs_symlink - create symlink + * @mnt_userns: user namespace of the mount the inode was found from + * @dir: inode of @dentry + * @dentry: pointer to dentry of the base directory + * @oldname: name of the file to link to + * + * Create a symlink. + * + * If the inode has been found through an idmapped mount the user namespace of + * the vfsmount must be passed through @mnt_userns. This function will then take + * care to map the inode according to @mnt_userns before checking permissions. + * On non-idmapped mounts or if permission checking is to be performed on the + * raw inode simply passs init_user_ns. + */ +int vfs_symlink(struct user_namespace *mnt_userns, struct inode *dir, + struct dentry *dentry, const char *oldname) { - int error = may_create(&init_user_ns, dir, dentry); + int error = may_create(mnt_userns, dir, dentry); if (error) return error; @@ -4073,8 +4192,13 @@ static long do_symlinkat(const char __user *oldname, int newdfd, goto out_putname; error = security_path_symlink(&path, dentry, from->name); - if (!error) - error = vfs_symlink(path.dentry->d_inode, dentry, from->name); + if (!error) { + struct user_namespace *mnt_userns; + + mnt_userns = mnt_user_ns(path.mnt); + error = vfs_symlink(mnt_userns, path.dentry->d_inode, dentry, + from->name); + } done_path_create(&path, dentry); if (retry_estale(error, lookup_flags)) { lookup_flags |= LOOKUP_REVAL; @@ -4099,6 +4223,7 @@ SYSCALL_DEFINE2(symlink, const char __user *, oldname, const char __user *, newn /** * vfs_link - create a new link * @old_dentry: object to be linked + * @mnt_userns: the user namespace of the mount * @dir: new parent * @new_dentry: where to create the new link * @delegated_inode: returns inode needing a delegation break @@ -4114,8 +4239,16 @@ SYSCALL_DEFINE2(symlink, const char __user *, oldname, const char __user *, newn * Alternatively, a caller may pass NULL for delegated_inode. This may * be appropriate for callers that expect the underlying filesystem not * to be NFS exported. + * + * If the inode has been found through an idmapped mount the user namespace of + * the vfsmount must be passed through @mnt_userns. This function will then take + * care to map the inode according to @mnt_userns before checking permissions. + * On non-idmapped mounts or if permission checking is to be performed on the + * raw inode simply passs init_user_ns. */ -int vfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry, struct inode **delegated_inode) +int vfs_link(struct dentry *old_dentry, struct user_namespace *mnt_userns, + struct inode *dir, struct dentry *new_dentry, + struct inode **delegated_inode) { struct inode *inode = old_dentry->d_inode; unsigned max_links = dir->i_sb->s_max_links; @@ -4124,7 +4257,7 @@ int vfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_de if (!inode) return -ENOENT; - error = may_create(&init_user_ns, dir, new_dentry); + error = may_create(mnt_userns, dir, new_dentry); if (error) return error; @@ -4141,7 +4274,7 @@ int vfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_de * be writen back improperly if their true value is unknown to * the vfs. */ - if (HAS_UNMAPPED_ID(&init_user_ns, inode)) + if (HAS_UNMAPPED_ID(mnt_userns, inode)) return -EPERM; if (!dir->i_op->link) return -EPERM; @@ -4188,6 +4321,7 @@ EXPORT_SYMBOL(vfs_link); static int do_linkat(int olddfd, const char __user *oldname, int newdfd, const char __user *newname, int flags) { + struct user_namespace *mnt_userns; struct dentry *new_dentry; struct path old_path, new_path; struct inode *delegated_inode = NULL; @@ -4229,7 +4363,9 @@ static int do_linkat(int olddfd, const char __user *oldname, int newdfd, error = security_path_link(old_path.dentry, &new_path, new_dentry); if (error) goto out_dput; - error = vfs_link(old_path.dentry, new_path.dentry->d_inode, new_dentry, &delegated_inode); + mnt_userns = mnt_user_ns(new_path.mnt); + error = vfs_link(old_path.dentry, mnt_userns, new_path.dentry->d_inode, + new_dentry, &delegated_inode); out_dput: done_path_create(&new_path, new_dentry); if (delegated_inode) { @@ -4263,12 +4399,14 @@ SYSCALL_DEFINE2(link, const char __user *, oldname, const char __user *, newname /** * vfs_rename - rename a filesystem object - * @old_dir: parent of source - * @old_dentry: source - * @new_dir: parent of destination - * @new_dentry: destination - * @delegated_inode: returns an inode needing a delegation break - * @flags: rename flags + * @old_mnt_userns: old user namespace of the mount the inode was found from + * @old_dir: parent of source + * @old_dentry: source + * @new_mnt_userns: new user namespace of the mount the inode was found from + * @new_dir: parent of destination + * @new_dentry: destination + * @delegated_inode: returns an inode needing a delegation break + * @flags: rename flags * * The caller must hold multiple mutexes--see lock_rename()). * @@ -4314,7 +4452,6 @@ SYSCALL_DEFINE2(link, const char __user *, oldname, const char __user *, newname int vfs_rename(struct renamedata *rd) { int error; - struct user_namespace *mnt_userns = &init_user_ns; struct inode *old_dir = rd->old_dir, *new_dir = rd->new_dir; struct dentry *old_dentry = rd->old_dentry; struct dentry *new_dentry = rd->new_dentry; @@ -4330,19 +4467,21 @@ int vfs_rename(struct renamedata *rd) if (source == target) return 0; - error = may_delete(mnt_userns, old_dir, old_dentry, is_dir); + error = may_delete(rd->old_mnt_userns, old_dir, old_dentry, is_dir); if (error) return error; if (!target) { - error = may_create(mnt_userns, new_dir, new_dentry); + error = may_create(rd->new_mnt_userns, new_dir, new_dentry); } else { new_is_dir = d_is_dir(new_dentry); if (!(flags & RENAME_EXCHANGE)) - error = may_delete(mnt_userns, new_dir, new_dentry, is_dir); + error = may_delete(rd->new_mnt_userns, new_dir, + new_dentry, is_dir); else - error = may_delete(mnt_userns, new_dir, new_dentry, new_is_dir); + error = may_delete(rd->new_mnt_userns, new_dir, + new_dentry, new_is_dir); } if (error) return error; @@ -4356,13 +4495,13 @@ int vfs_rename(struct renamedata *rd) */ if (new_dir != old_dir) { if (is_dir) { - error = inode_permission(&init_user_ns, source, + error = inode_permission(rd->old_mnt_userns, source, MAY_WRITE); if (error) return error; } if ((flags & RENAME_EXCHANGE) && new_is_dir) { - error = inode_permission(&init_user_ns, target, + error = inode_permission(rd->new_mnt_userns, target, MAY_WRITE); if (error) return error; @@ -4552,8 +4691,10 @@ int do_renameat2(int olddfd, struct filename *from, int newdfd, rd.old_dir = old_path.dentry->d_inode; rd.old_dentry = old_dentry; + rd.old_mnt_userns = mnt_user_ns(old_path.mnt); rd.new_dir = new_path.dentry->d_inode; rd.new_dentry = new_dentry; + rd.new_mnt_userns = mnt_user_ns(new_path.mnt); rd.delegated_inode = &delegated_inode; rd.flags = flags; error = vfs_rename(&rd); diff --git a/fs/nfsd/nfs4recover.c b/fs/nfsd/nfs4recover.c index 186fa2c2c6ba..891395c6c7d3 100644 --- a/fs/nfsd/nfs4recover.c +++ b/fs/nfsd/nfs4recover.c @@ -233,7 +233,7 @@ nfsd4_create_clid_dir(struct nfs4_client *clp) * as well be forgiving and just succeed silently. */ goto out_put; - status = vfs_mkdir(d_inode(dir), dentry, S_IRWXU); + status = vfs_mkdir(&init_user_ns, d_inode(dir), dentry, S_IRWXU); out_put: dput(dentry); out_unlock: @@ -353,7 +353,7 @@ nfsd4_unlink_clid_dir(char *name, int namlen, struct nfsd_net *nn) status = -ENOENT; if (d_really_is_negative(dentry)) goto out; - status = vfs_rmdir(d_inode(dir), dentry); + status = vfs_rmdir(&init_user_ns, d_inode(dir), dentry); out: dput(dentry); out_unlock: @@ -443,7 +443,7 @@ purge_old(struct dentry *parent, struct dentry *child, struct nfsd_net *nn) if (nfs4_has_reclaimed_state(name, nn)) goto out_free; - status = vfs_rmdir(d_inode(parent), child); + status = vfs_rmdir(&init_user_ns, d_inode(parent), child); if (status) printk("failed to remove client recovery directory %pd\n", child); diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index f7d83ff2b44e..fab873178140 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -1255,12 +1255,12 @@ nfsd_create_locked(struct svc_rqst *rqstp, struct svc_fh *fhp, host_err = 0; switch (type) { case S_IFREG: - host_err = vfs_create(dirp, dchild, iap->ia_mode, true); + host_err = vfs_create(&init_user_ns, dirp, dchild, iap->ia_mode, true); if (!host_err) nfsd_check_ignore_resizing(iap); break; case S_IFDIR: - host_err = vfs_mkdir(dirp, dchild, iap->ia_mode); + host_err = vfs_mkdir(&init_user_ns, dirp, dchild, iap->ia_mode); if (!host_err && unlikely(d_unhashed(dchild))) { struct dentry *d; d = lookup_one_len(dchild->d_name.name, @@ -1288,7 +1288,8 @@ nfsd_create_locked(struct svc_rqst *rqstp, struct svc_fh *fhp, case S_IFBLK: case S_IFIFO: case S_IFSOCK: - host_err = vfs_mknod(dirp, dchild, iap->ia_mode, rdev); + host_err = vfs_mknod(&init_user_ns, dirp, dchild, + iap->ia_mode, rdev); break; default: printk(KERN_WARNING "nfsd: bad file type %o in nfsd_create\n", @@ -1486,7 +1487,7 @@ do_nfsd_create(struct svc_rqst *rqstp, struct svc_fh *fhp, if (!IS_POSIXACL(dirp)) iap->ia_mode &= ~current_umask(); - host_err = vfs_create(dirp, dchild, iap->ia_mode, true); + host_err = vfs_create(&init_user_ns, dirp, dchild, iap->ia_mode, true); if (host_err < 0) { fh_drop_write(fhp); goto out_nfserr; @@ -1610,7 +1611,7 @@ nfsd_symlink(struct svc_rqst *rqstp, struct svc_fh *fhp, if (IS_ERR(dnew)) goto out_nfserr; - host_err = vfs_symlink(d_inode(dentry), dnew, path); + host_err = vfs_symlink(&init_user_ns, d_inode(dentry), dnew, path); err = nfserrno(host_err); if (!err) err = nfserrno(commit_metadata(fhp)); @@ -1678,7 +1679,7 @@ nfsd_link(struct svc_rqst *rqstp, struct svc_fh *ffhp, err = nfserr_noent; if (d_really_is_negative(dold)) goto out_dput; - host_err = vfs_link(dold, dirp, dnew, NULL); + host_err = vfs_link(dold, &init_user_ns, dirp, dnew, NULL); if (!host_err) { err = nfserrno(commit_metadata(ffhp)); if (!err) @@ -1799,8 +1800,10 @@ nfsd_rename(struct svc_rqst *rqstp, struct svc_fh *ffhp, char *fname, int flen, goto out_dput_old; } else { struct renamedata rd = { + .old_mnt_userns = &init_user_ns, .old_dir = fdir, .old_dentry = odentry, + .new_mnt_userns = &init_user_ns, .new_dir = tdir, .new_dentry = ndentry, }; @@ -1891,9 +1894,9 @@ nfsd_unlink(struct svc_rqst *rqstp, struct svc_fh *fhp, int type, if (type != S_IFDIR) { if (rdentry->d_sb->s_export_op->flags & EXPORT_OP_CLOSE_BEFORE_UNLINK) nfsd_close_cached_files(rdentry); - host_err = vfs_unlink(dirp, rdentry, NULL); + host_err = vfs_unlink(&init_user_ns, dirp, rdentry, NULL); } else { - host_err = vfs_rmdir(dirp, rdentry); + host_err = vfs_rmdir(&init_user_ns, dirp, rdentry); } if (!host_err) diff --git a/fs/overlayfs/dir.c b/fs/overlayfs/dir.c index d75c96cb18c3..6904cc2ed7bb 100644 --- a/fs/overlayfs/dir.c +++ b/fs/overlayfs/dir.c @@ -821,9 +821,9 @@ static int ovl_remove_upper(struct dentry *dentry, bool is_dir, goto out_dput_upper; if (is_dir) - err = vfs_rmdir(dir, upper); + err = vfs_rmdir(&init_user_ns, dir, upper); else - err = vfs_unlink(dir, upper, NULL); + err = vfs_unlink(&init_user_ns, dir, upper, NULL); ovl_dir_modified(dentry->d_parent, ovl_type_origin(dentry)); /* diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h index 426899681df7..5e9eb46e741a 100644 --- a/fs/overlayfs/overlayfs.h +++ b/fs/overlayfs/overlayfs.h @@ -123,7 +123,7 @@ static inline const char *ovl_xattr(struct ovl_fs *ofs, enum ovl_xattr ox) static inline int ovl_do_rmdir(struct inode *dir, struct dentry *dentry) { - int err = vfs_rmdir(dir, dentry); + int err = vfs_rmdir(&init_user_ns, dir, dentry); pr_debug("rmdir(%pd2) = %i\n", dentry, err); return err; @@ -131,7 +131,7 @@ static inline int ovl_do_rmdir(struct inode *dir, struct dentry *dentry) static inline int ovl_do_unlink(struct inode *dir, struct dentry *dentry) { - int err = vfs_unlink(dir, dentry, NULL); + int err = vfs_unlink(&init_user_ns, dir, dentry, NULL); pr_debug("unlink(%pd2) = %i\n", dentry, err); return err; @@ -140,7 +140,7 @@ static inline int ovl_do_unlink(struct inode *dir, struct dentry *dentry) static inline int ovl_do_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) { - int err = vfs_link(old_dentry, dir, new_dentry, NULL); + int err = vfs_link(old_dentry, &init_user_ns, dir, new_dentry, NULL); pr_debug("link(%pd2, %pd2) = %i\n", old_dentry, new_dentry, err); return err; @@ -149,7 +149,7 @@ static inline int ovl_do_link(struct dentry *old_dentry, struct inode *dir, static inline int ovl_do_create(struct inode *dir, struct dentry *dentry, umode_t mode) { - int err = vfs_create(dir, dentry, mode, true); + int err = vfs_create(&init_user_ns, dir, dentry, mode, true); pr_debug("create(%pd2, 0%o) = %i\n", dentry, mode, err); return err; @@ -158,7 +158,7 @@ static inline int ovl_do_create(struct inode *dir, struct dentry *dentry, static inline int ovl_do_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) { - int err = vfs_mkdir(dir, dentry, mode); + int err = vfs_mkdir(&init_user_ns, dir, dentry, mode); pr_debug("mkdir(%pd2, 0%o) = %i\n", dentry, mode, err); return err; } @@ -166,7 +166,7 @@ static inline int ovl_do_mkdir(struct inode *dir, struct dentry *dentry, static inline int ovl_do_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev) { - int err = vfs_mknod(dir, dentry, mode, dev); + int err = vfs_mknod(&init_user_ns, dir, dentry, mode, dev); pr_debug("mknod(%pd2, 0%o, 0%o) = %i\n", dentry, mode, dev, err); return err; @@ -175,7 +175,7 @@ static inline int ovl_do_mknod(struct inode *dir, struct dentry *dentry, static inline int ovl_do_symlink(struct inode *dir, struct dentry *dentry, const char *oldname) { - int err = vfs_symlink(dir, dentry, oldname); + int err = vfs_symlink(&init_user_ns, dir, dentry, oldname); pr_debug("symlink(\"%s\", %pd2) = %i\n", oldname, dentry, err); return err; @@ -215,8 +215,10 @@ static inline int ovl_do_rename(struct inode *olddir, struct dentry *olddentry, { int err; struct renamedata rd = { + .old_mnt_userns = &init_user_ns, .old_dir = olddir, .old_dentry = olddentry, + .new_mnt_userns = &init_user_ns, .new_dir = newdir, .new_dentry = newdentry, .flags = flags, @@ -233,14 +235,14 @@ static inline int ovl_do_rename(struct inode *olddir, struct dentry *olddentry, static inline int ovl_do_whiteout(struct inode *dir, struct dentry *dentry) { - int err = vfs_whiteout(dir, dentry); + int err = vfs_whiteout(&init_user_ns, dir, dentry); pr_debug("whiteout(%pd2) = %i\n", dentry, err); return err; } static inline struct dentry *ovl_do_tmpfile(struct dentry *dentry, umode_t mode) { - struct dentry *ret = vfs_tmpfile(dentry, mode, 0); + struct dentry *ret = vfs_tmpfile(&init_user_ns, dentry, mode, 0); int err = PTR_ERR_OR_ZERO(ret); pr_debug("tmpfile(%pd2, 0%o) = %i\n", dentry, mode, err); diff --git a/include/linux/fs.h b/include/linux/fs.h index 430e457f67f1..29d7b2fe7de4 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1768,17 +1768,25 @@ bool inode_owner_or_capable(struct user_namespace *mnt_userns, /* * VFS helper functions.. */ -extern int vfs_create(struct inode *, struct dentry *, umode_t, bool); -extern int vfs_mkdir(struct inode *, struct dentry *, umode_t); -extern int vfs_mknod(struct inode *, struct dentry *, umode_t, dev_t); -extern int vfs_symlink(struct inode *, struct dentry *, const char *); -extern int vfs_link(struct dentry *, struct inode *, struct dentry *, struct inode **); -extern int vfs_rmdir(struct inode *, struct dentry *); -extern int vfs_unlink(struct inode *, struct dentry *, struct inode **); +int vfs_create(struct user_namespace *, struct inode *, + struct dentry *, umode_t, bool); +int vfs_mkdir(struct user_namespace *, struct inode *, + struct dentry *, umode_t); +int vfs_mknod(struct user_namespace *, struct inode *, struct dentry *, + umode_t, dev_t); +int vfs_symlink(struct user_namespace *, struct inode *, + struct dentry *, const char *); +int vfs_link(struct dentry *, struct user_namespace *, struct inode *, + struct dentry *, struct inode **); +int vfs_rmdir(struct user_namespace *, struct inode *, struct dentry *); +int vfs_unlink(struct user_namespace *, struct inode *, struct dentry *, + struct inode **); struct renamedata { + struct user_namespace *old_mnt_userns; struct inode *old_dir; struct dentry *old_dentry; + struct user_namespace *new_mnt_userns; struct inode *new_dir; struct dentry *new_dentry; struct inode **delegated_inode; @@ -1787,13 +1795,15 @@ struct renamedata { int vfs_rename(struct renamedata *); -static inline int vfs_whiteout(struct inode *dir, struct dentry *dentry) +static inline int vfs_whiteout(struct user_namespace *mnt_userns, + struct inode *dir, struct dentry *dentry) { - return vfs_mknod(dir, dentry, S_IFCHR | WHITEOUT_MODE, WHITEOUT_DEV); + return vfs_mknod(mnt_userns, dir, dentry, S_IFCHR | WHITEOUT_MODE, + WHITEOUT_DEV); } -extern struct dentry *vfs_tmpfile(struct dentry *dentry, umode_t mode, - int open_flag); +struct dentry *vfs_tmpfile(struct user_namespace *mnt_userns, + struct dentry *dentry, umode_t mode, int open_flag); int vfs_mkobj(struct dentry *, umode_t, int (*f)(struct dentry *, umode_t, void *), diff --git a/ipc/mqueue.c b/ipc/mqueue.c index 693f01fe1216..fcd56e077733 100644 --- a/ipc/mqueue.c +++ b/ipc/mqueue.c @@ -965,7 +965,8 @@ SYSCALL_DEFINE1(mq_unlink, const char __user *, u_name) err = -ENOENT; } else { ihold(inode); - err = vfs_unlink(d_inode(dentry->d_parent), dentry, NULL); + err = vfs_unlink(&init_user_ns, d_inode(dentry->d_parent), + dentry, NULL); } dput(dentry); diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c index 18453d15dddf..9a1f3c04402e 100644 --- a/net/unix/af_unix.c +++ b/net/unix/af_unix.c @@ -996,7 +996,8 @@ static int unix_mknod(const char *sun_path, umode_t mode, struct path *res) */ err = security_path_mknod(&path, dentry, mode, 0); if (!err) { - err = vfs_mknod(d_inode(path.dentry), dentry, mode, 0); + err = vfs_mknod(&init_user_ns, d_inode(path.dentry), dentry, + mode, 0); if (!err) { res->mnt = mntget(path.mnt); res->dentry = dget(dentry);