diff options
| -rw-r--r-- | fs/fuse/Kconfig | 1 | ||||
| -rw-r--r-- | fs/fuse/Makefile | 2 | ||||
| -rw-r--r-- | fs/fuse/acl.c | 99 | ||||
| -rw-r--r-- | fs/fuse/dir.c | 16 | ||||
| -rw-r--r-- | fs/fuse/fuse_i.h | 14 | ||||
| -rw-r--r-- | fs/fuse/inode.c | 9 | ||||
| -rw-r--r-- | fs/fuse/xattr.c | 18 | ||||
| -rw-r--r-- | include/uapi/linux/fuse.h | 3 |
8 files changed, 155 insertions, 7 deletions
diff --git a/fs/fuse/Kconfig b/fs/fuse/Kconfig index 1b2f6c2c3aaf..76f09ce7e5b2 100644 --- a/fs/fuse/Kconfig +++ b/fs/fuse/Kconfig @@ -1,5 +1,6 @@ config FUSE_FS tristate "FUSE (Filesystem in Userspace) support" + select FS_POSIX_ACL help With FUSE it is possible to implement a fully functional filesystem in a userspace program. diff --git a/fs/fuse/Makefile b/fs/fuse/Makefile index 448aa27ada00..60da84a86dab 100644 --- a/fs/fuse/Makefile +++ b/fs/fuse/Makefile @@ -5,4 +5,4 @@ obj-$(CONFIG_FUSE_FS) += fuse.o obj-$(CONFIG_CUSE) += cuse.o -fuse-objs := dev.o dir.o file.o inode.o control.o xattr.o +fuse-objs := dev.o dir.o file.o inode.o control.o xattr.o acl.o diff --git a/fs/fuse/acl.c b/fs/fuse/acl.c new file mode 100644 index 000000000000..ec85765502f1 --- /dev/null +++ b/fs/fuse/acl.c @@ -0,0 +1,99 @@ +/* + * FUSE: Filesystem in Userspace + * Copyright (C) 2016 Canonical Ltd. <seth.forshee@canonical.com> + * + * This program can be distributed under the terms of the GNU GPL. + * See the file COPYING. + */ + +#include "fuse_i.h" + +#include <linux/posix_acl.h> +#include <linux/posix_acl_xattr.h> + +struct posix_acl *fuse_get_acl(struct inode *inode, int type) +{ + struct fuse_conn *fc = get_fuse_conn(inode); + int size; + const char *name; + void *value = NULL; + struct posix_acl *acl; + + if (!fc->posix_acl || fc->no_getxattr) + return NULL; + + if (type == ACL_TYPE_ACCESS) + name = XATTR_NAME_POSIX_ACL_ACCESS; + else if (type == ACL_TYPE_DEFAULT) + name = XATTR_NAME_POSIX_ACL_DEFAULT; + else + return ERR_PTR(-EOPNOTSUPP); + + value = kmalloc(PAGE_SIZE, GFP_KERNEL); + if (!value) + return ERR_PTR(-ENOMEM); + size = fuse_getxattr(inode, name, value, PAGE_SIZE); + if (size > 0) + acl = posix_acl_from_xattr(&init_user_ns, value, size); + else if ((size == 0) || (size == -ENODATA) || + (size == -EOPNOTSUPP && fc->no_getxattr)) + acl = NULL; + else if (size == -ERANGE) + acl = ERR_PTR(-E2BIG); + else + acl = ERR_PTR(size); + + kfree(value); + return acl; +} + +int fuse_set_acl(struct inode *inode, struct posix_acl *acl, int type) +{ + struct fuse_conn *fc = get_fuse_conn(inode); + const char *name; + int ret; + + if (!fc->posix_acl || fc->no_setxattr) + return -EOPNOTSUPP; + + if (type == ACL_TYPE_ACCESS) + name = XATTR_NAME_POSIX_ACL_ACCESS; + else if (type == ACL_TYPE_DEFAULT) + name = XATTR_NAME_POSIX_ACL_DEFAULT; + else + return -EINVAL; + + if (acl) { + /* + * Fuse userspace is responsible for updating access + * permissions in the inode, if needed. fuse_setxattr + * invalidates the inode attributes, which will force + * them to be refreshed the next time they are used, + * and it also updates i_ctime. + */ + size_t size = posix_acl_xattr_size(acl->a_count); + void *value; + + if (size > PAGE_SIZE) + return -E2BIG; + + value = kmalloc(size, GFP_KERNEL); + if (!value) + return -ENOMEM; + + ret = posix_acl_to_xattr(&init_user_ns, acl, value, size); + if (ret < 0) { + kfree(value); + return ret; + } + + ret = fuse_setxattr(inode, name, value, size, 0); + kfree(value); + } else { + ret = fuse_removexattr(inode, name); + } + forget_all_cached_acls(inode); + fuse_invalidate_attr(inode); + + return ret; +} diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c index 7cb68b18eb3f..3076f48d86a6 100644 --- a/fs/fuse/dir.c +++ b/fs/fuse/dir.c @@ -14,6 +14,7 @@ #include <linux/namei.h> #include <linux/slab.h> #include <linux/xattr.h> +#include <linux/posix_acl.h> static bool fuse_use_readdirplus(struct inode *dir, struct dir_context *ctx) { @@ -244,6 +245,7 @@ static int fuse_dentry_revalidate(struct dentry *entry, unsigned int flags) if (ret || (outarg.attr.mode ^ inode->i_mode) & S_IFMT) goto invalid; + forget_all_cached_acls(inode); fuse_change_attributes(inode, &outarg.attr, entry_attr_timeout(&outarg), attr_version); @@ -918,6 +920,7 @@ int fuse_update_attributes(struct inode *inode, struct kstat *stat, if (time_before64(fi->i_time, get_jiffies_64())) { r = true; + forget_all_cached_acls(inode); err = fuse_do_getattr(inode, stat, file); } else { r = false; @@ -1065,6 +1068,7 @@ static int fuse_perm_getattr(struct inode *inode, int mask) if (mask & MAY_NOT_BLOCK) return -ECHILD; + forget_all_cached_acls(inode); return fuse_do_getattr(inode, NULL, NULL); } @@ -1234,6 +1238,7 @@ retry: fi->nlookup++; spin_unlock(&fc->lock); + forget_all_cached_acls(inode); fuse_change_attributes(inode, &o->attr, entry_attr_timeout(o), attr_version); @@ -1748,6 +1753,13 @@ static int fuse_setattr(struct dentry *entry, struct iattr *attr) ret = fuse_do_setattr(inode, attr, file); if (!ret) { + /* + * If filesystem supports acls it may have updated acl xattrs in + * the filesystem, so forget cached acls for the inode. + */ + if (fc->posix_acl) + forget_all_cached_acls(inode); + /* Directory mode changed, may need to revalidate access */ if (d_is_dir(entry) && (attr->ia_valid & ATTR_MODE)) fuse_invalidate_entry_cache(entry); @@ -1785,6 +1797,8 @@ static const struct inode_operations fuse_dir_inode_operations = { .getxattr = generic_getxattr, .listxattr = fuse_listxattr, .removexattr = generic_removexattr, + .get_acl = fuse_get_acl, + .set_acl = fuse_set_acl, }; static const struct file_operations fuse_dir_operations = { @@ -1806,6 +1820,8 @@ static const struct inode_operations fuse_common_inode_operations = { .getxattr = generic_getxattr, .listxattr = fuse_listxattr, .removexattr = generic_removexattr, + .get_acl = fuse_get_acl, + .set_acl = fuse_set_acl, }; static const struct inode_operations fuse_symlink_inode_operations = { diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h index 9940a648c985..e8d96ec22533 100644 --- a/fs/fuse/fuse_i.h +++ b/fs/fuse/fuse_i.h @@ -23,6 +23,7 @@ #include <linux/poll.h> #include <linux/workqueue.h> #include <linux/kref.h> +#include <linux/xattr.h> /** Max number of pages that can be used in a single read request */ #define FUSE_MAX_PAGES_PER_REQ 32 @@ -627,6 +628,9 @@ struct fuse_conn { /** Is lseek not implemented by fs? */ unsigned no_lseek:1; + /** Does the filesystem support posix acls? */ + unsigned posix_acl:1; + /** The number of requests waiting for completion */ atomic_t num_waiting; @@ -971,7 +975,17 @@ void fuse_set_initialized(struct fuse_conn *fc); void fuse_unlock_inode(struct inode *inode); void fuse_lock_inode(struct inode *inode); +int fuse_setxattr(struct inode *inode, const char *name, const void *value, + size_t size, int flags); +ssize_t fuse_getxattr(struct inode *inode, const char *name, void *value, + size_t size); ssize_t fuse_listxattr(struct dentry *entry, char *list, size_t size); +int fuse_removexattr(struct inode *inode, const char *name); extern const struct xattr_handler *fuse_xattr_handlers[]; +extern const struct xattr_handler *fuse_acl_xattr_handlers[]; + +struct posix_acl; +struct posix_acl *fuse_get_acl(struct inode *inode, int type); +int fuse_set_acl(struct inode *inode, struct posix_acl *acl, int type); #endif /* _FS_FUSE_I_H */ diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c index b965934939cb..16ac9d86c507 100644 --- a/fs/fuse/inode.c +++ b/fs/fuse/inode.c @@ -20,6 +20,7 @@ #include <linux/random.h> #include <linux/sched.h> #include <linux/exportfs.h> +#include <linux/posix_acl.h> MODULE_AUTHOR("Miklos Szeredi <miklos@szeredi.hu>"); MODULE_DESCRIPTION("Filesystem in Userspace"); @@ -340,6 +341,7 @@ int fuse_reverse_inval_inode(struct super_block *sb, u64 nodeid, return -ENOENT; fuse_invalidate_attr(inode); + forget_all_cached_acls(inode); if (offset >= 0) { pg_start = offset >> PAGE_SHIFT; if (len <= 0) @@ -914,6 +916,11 @@ static void process_init_reply(struct fuse_conn *fc, struct fuse_req *req) fc->handle_killpriv = 1; if (arg->time_gran && arg->time_gran <= 1000000000) fc->sb->s_time_gran = arg->time_gran; + if ((arg->flags & FUSE_POSIX_ACL)) { + fc->flags |= FUSE_DEFAULT_PERMISSIONS; + fc->posix_acl = 1; + fc->sb->s_xattr = fuse_acl_xattr_handlers; + } } else { ra_pages = fc->max_read / PAGE_SIZE; fc->no_lock = 1; @@ -943,7 +950,7 @@ static void fuse_send_init(struct fuse_conn *fc, struct fuse_req *req) FUSE_FLOCK_LOCKS | FUSE_HAS_IOCTL_DIR | FUSE_AUTO_INVAL_DATA | FUSE_DO_READDIRPLUS | FUSE_READDIRPLUS_AUTO | FUSE_ASYNC_DIO | FUSE_WRITEBACK_CACHE | FUSE_NO_OPEN_SUPPORT | - FUSE_PARALLEL_DIROPS | FUSE_HANDLE_KILLPRIV; + FUSE_PARALLEL_DIROPS | FUSE_HANDLE_KILLPRIV | FUSE_POSIX_ACL; req->in.h.opcode = FUSE_INIT; req->in.numargs = 1; req->in.args[0].size = sizeof(*arg); diff --git a/fs/fuse/xattr.c b/fs/fuse/xattr.c index e22980f0a9e2..04b097f29d8a 100644 --- a/fs/fuse/xattr.c +++ b/fs/fuse/xattr.c @@ -9,9 +9,10 @@ #include "fuse_i.h" #include <linux/xattr.h> +#include <linux/posix_acl_xattr.h> -static int fuse_setxattr(struct inode *inode, const char *name, - const void *value, size_t size, int flags) +int fuse_setxattr(struct inode *inode, const char *name, const void *value, + size_t size, int flags) { struct fuse_conn *fc = get_fuse_conn(inode); FUSE_ARGS(args); @@ -45,8 +46,8 @@ static int fuse_setxattr(struct inode *inode, const char *name, return err; } -static ssize_t fuse_getxattr(struct inode *inode, const char *name, - void *value, size_t size) +ssize_t fuse_getxattr(struct inode *inode, const char *name, void *value, + size_t size) { struct fuse_conn *fc = get_fuse_conn(inode); FUSE_ARGS(args); @@ -147,7 +148,7 @@ ssize_t fuse_listxattr(struct dentry *entry, char *list, size_t size) return ret; } -static int fuse_removexattr(struct inode *inode, const char *name) +int fuse_removexattr(struct inode *inode, const char *name) { struct fuse_conn *fc = get_fuse_conn(inode); FUSE_ARGS(args); @@ -201,3 +202,10 @@ const struct xattr_handler *fuse_xattr_handlers[] = { &fuse_xattr_handler, NULL }; + +const struct xattr_handler *fuse_acl_xattr_handlers[] = { + &posix_acl_access_xattr_handler, + &posix_acl_default_xattr_handler, + &fuse_xattr_handler, + NULL +}; diff --git a/include/uapi/linux/fuse.h b/include/uapi/linux/fuse.h index 14ca2f10d354..42fa977e3b14 100644 --- a/include/uapi/linux/fuse.h +++ b/include/uapi/linux/fuse.h @@ -111,6 +111,7 @@ * * 7.26 * - add FUSE_HANDLE_KILLPRIV + * - add FUSE_POSIX_ACL */ #ifndef _LINUX_FUSE_H @@ -242,6 +243,7 @@ struct fuse_file_lock { * FUSE_NO_OPEN_SUPPORT: kernel supports zero-message opens * FUSE_PARALLEL_DIROPS: allow parallel lookups and readdir * FUSE_HANDLE_KILLPRIV: fs handles killing suid/sgid/cap on write/chown/trunc + * FUSE_POSIX_ACL: filesystem supports posix acls */ #define FUSE_ASYNC_READ (1 << 0) #define FUSE_POSIX_LOCKS (1 << 1) @@ -263,6 +265,7 @@ struct fuse_file_lock { #define FUSE_NO_OPEN_SUPPORT (1 << 17) #define FUSE_PARALLEL_DIROPS (1 << 18) #define FUSE_HANDLE_KILLPRIV (1 << 19) +#define FUSE_POSIX_ACL (1 << 20) /** * CUSE INIT request/reply flags |
