diff options
Diffstat (limited to 'fs/fuse')
| -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/dev.c | 64 | ||||
| -rw-r--r-- | fs/fuse/dir.c | 288 | ||||
| -rw-r--r-- | fs/fuse/file.c | 68 | ||||
| -rw-r--r-- | fs/fuse/fuse_i.h | 40 | ||||
| -rw-r--r-- | fs/fuse/inode.c | 28 | ||||
| -rw-r--r-- | fs/fuse/xattr.c | 211 |
9 files changed, 498 insertions, 303 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 e95eeb445e58..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 +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/dev.c b/fs/fuse/dev.c index a94d2ed81ab4..70ea57c7b6bb 100644 --- a/fs/fuse/dev.c +++ b/fs/fuse/dev.c @@ -728,7 +728,7 @@ static int fuse_copy_fill(struct fuse_copy_state *cs) struct pipe_buffer *buf = cs->pipebufs; if (!cs->write) { - err = buf->ops->confirm(cs->pipe, buf); + err = pipe_buf_confirm(cs->pipe, buf); if (err) return err; @@ -767,7 +767,6 @@ static int fuse_copy_fill(struct fuse_copy_state *cs) cs->len = err; cs->offset = off; cs->pg = page; - cs->offset = off; iov_iter_advance(cs->iter, err); } @@ -828,7 +827,7 @@ static int fuse_try_move_page(struct fuse_copy_state *cs, struct page **pagep) fuse_copy_finish(cs); - err = buf->ops->confirm(cs->pipe, buf); + err = pipe_buf_confirm(cs->pipe, buf); if (err) return err; @@ -841,7 +840,7 @@ static int fuse_try_move_page(struct fuse_copy_state *cs, struct page **pagep) if (cs->len != PAGE_SIZE) goto out_fallback; - if (buf->ops->steal(cs->pipe, buf) != 0) + if (pipe_buf_steal(cs->pipe, buf) != 0) goto out_fallback; newpage = buf->page; @@ -1342,9 +1341,8 @@ static ssize_t fuse_dev_splice_read(struct file *in, loff_t *ppos, struct pipe_inode_info *pipe, size_t len, unsigned int flags) { - int ret; + int total, ret; int page_nr = 0; - int do_wakeup = 0; struct pipe_buffer *bufs; struct fuse_copy_state cs; struct fuse_dev *fud = fuse_get_dev(in); @@ -1363,52 +1361,23 @@ static ssize_t fuse_dev_splice_read(struct file *in, loff_t *ppos, if (ret < 0) goto out; - ret = 0; - pipe_lock(pipe); - - if (!pipe->readers) { - send_sig(SIGPIPE, current, 0); - if (!ret) - ret = -EPIPE; - goto out_unlock; - } - if (pipe->nrbufs + cs.nr_segs > pipe->buffers) { ret = -EIO; - goto out_unlock; + goto out; } - while (page_nr < cs.nr_segs) { - int newbuf = (pipe->curbuf + pipe->nrbufs) & (pipe->buffers - 1); - struct pipe_buffer *buf = pipe->bufs + newbuf; - - buf->page = bufs[page_nr].page; - buf->offset = bufs[page_nr].offset; - buf->len = bufs[page_nr].len; + for (ret = total = 0; page_nr < cs.nr_segs; total += ret) { /* * Need to be careful about this. Having buf->ops in module * code can Oops if the buffer persists after module unload. */ - buf->ops = &nosteal_pipe_buf_ops; - - pipe->nrbufs++; - page_nr++; - ret += buf->len; - - if (pipe->files) - do_wakeup = 1; - } - -out_unlock: - pipe_unlock(pipe); - - if (do_wakeup) { - smp_mb(); - if (waitqueue_active(&pipe->wait)) - wake_up_interruptible(&pipe->wait); - kill_fasync(&pipe->fasync_readers, SIGIO, POLL_IN); + bufs[page_nr].ops = &nosteal_pipe_buf_ops; + ret = add_to_pipe(pipe, &bufs[page_nr++]); + if (unlikely(ret < 0)) + break; } - + if (total) + ret = total; out: for (; page_nr < cs.nr_segs; page_nr++) put_page(bufs[page_nr].page); @@ -1993,7 +1962,7 @@ static ssize_t fuse_dev_splice_write(struct pipe_inode_info *pipe, pipe->curbuf = (pipe->curbuf + 1) & (pipe->buffers - 1); pipe->nrbufs--; } else { - ibuf->ops->get(pipe, ibuf); + pipe_buf_get(pipe, ibuf); *obuf = *ibuf; obuf->flags &= ~PIPE_BUF_FLAG_GIFT; obuf->len = rem; @@ -2015,10 +1984,9 @@ static ssize_t fuse_dev_splice_write(struct pipe_inode_info *pipe, ret = fuse_dev_do_write(fud, &cs, len); - for (idx = 0; idx < nbuf; idx++) { - struct pipe_buffer *buf = &bufs[idx]; - buf->ops->release(pipe, buf); - } + for (idx = 0; idx < nbuf; idx++) + pipe_buf_release(pipe, &bufs[idx]); + out: kfree(bufs); return ret; diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c index b23502174682..a430c19607f4 100644 --- a/fs/fuse/dir.c +++ b/fs/fuse/dir.c @@ -13,6 +13,8 @@ #include <linux/sched.h> #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) { @@ -37,47 +39,39 @@ static void fuse_advise_use_readdirplus(struct inode *dir) set_bit(FUSE_I_ADVISE_RDPLUS, &fi->state); } -#if BITS_PER_LONG >= 64 +union fuse_dentry { + u64 time; + struct rcu_head rcu; +}; + static inline void fuse_dentry_settime(struct dentry *entry, u64 time) { - entry->d_time = time; + ((union fuse_dentry *) entry->d_fsdata)->time = time; } static inline u64 fuse_dentry_time(struct dentry *entry) { - return entry->d_time; -} -#else -/* - * On 32 bit archs store the high 32 bits of time in d_fsdata - */ -static void fuse_dentry_settime(struct dentry *entry, u64 time) -{ - entry->d_time = time; - entry->d_fsdata = (void *) (unsigned long) (time >> 32); -} - -static u64 fuse_dentry_time(struct dentry *entry) -{ - return (u64) entry->d_time + - ((u64) (unsigned long) entry->d_fsdata << 32); + return ((union fuse_dentry *) entry->d_fsdata)->time; } -#endif /* * FUSE caches dentries and attributes with separate timeout. The * time in jiffies until the dentry/attributes are valid is stored in - * dentry->d_time and fuse_inode->i_time respectively. + * dentry->d_fsdata and fuse_inode->i_time respectively. */ /* * Calculate the time in jiffies until a dentry/attributes are valid */ -static u64 time_to_jiffies(unsigned long sec, unsigned long nsec) +static u64 time_to_jiffies(u64 sec, u32 nsec) { if (sec || nsec) { - struct timespec ts = {sec, nsec}; - return get_jiffies_64() + timespec_to_jiffies(&ts); + struct timespec64 ts = { + sec, + max_t(u32, nsec, NSEC_PER_SEC - 1) + }; + + return get_jiffies_64() + timespec64_to_jiffies(&ts); } else return 0; } @@ -243,6 +237,7 @@ 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); @@ -272,8 +267,23 @@ static int invalid_nodeid(u64 nodeid) return !nodeid || nodeid == FUSE_ROOT_ID; } +static int fuse_dentry_init(struct dentry *dentry) +{ + dentry->d_fsdata = kzalloc(sizeof(union fuse_dentry), GFP_KERNEL); + + return dentry->d_fsdata ? 0 : -ENOMEM; +} +static void fuse_dentry_release(struct dentry *dentry) +{ + union fuse_dentry *fd = dentry->d_fsdata; + + kfree_rcu(fd, rcu); +} + const struct dentry_operations fuse_dentry_operations = { .d_revalidate = fuse_dentry_revalidate, + .d_init = fuse_dentry_init, + .d_release = fuse_dentry_release, }; int fuse_valid_type(int m) @@ -634,7 +644,7 @@ static int fuse_symlink(struct inode *dir, struct dentry *entry, return create_new_entry(fc, &args, dir, entry, S_IFLNK); } -static inline void fuse_update_ctime(struct inode *inode) +void fuse_update_ctime(struct inode *inode) { if (!IS_NOCMTIME(inode)) { inode->i_ctime = current_fs_time(inode->i_sb); @@ -917,6 +927,7 @@ 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; @@ -1017,7 +1028,7 @@ int fuse_allow_current_process(struct fuse_conn *fc) { const struct cred *cred; - if (fc->flags & FUSE_ALLOW_OTHER) + if (fc->allow_other) return 1; cred = current_cred(); @@ -1064,6 +1075,7 @@ 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); } @@ -1092,7 +1104,7 @@ static int fuse_permission(struct inode *inode, int mask) /* * If attributes are needed, refresh them before proceeding */ - if ((fc->flags & FUSE_DEFAULT_PERMISSIONS) || + if (fc->default_permissions || ((mask & MAY_EXEC) && S_ISREG(inode->i_mode))) { struct fuse_inode *fi = get_fuse_inode(inode); @@ -1105,7 +1117,7 @@ static int fuse_permission(struct inode *inode, int mask) } } - if (fc->flags & FUSE_DEFAULT_PERMISSIONS) { + if (fc->default_permissions) { err = generic_permission(inode, mask); /* If permission is denied, try to refresh file @@ -1233,6 +1245,7 @@ retry: fi->nlookup++; spin_unlock(&fc->lock); + forget_all_cached_acls(inode); fuse_change_attributes(inode, &o->attr, entry_attr_timeout(o), attr_version); @@ -1606,7 +1619,7 @@ int fuse_do_setattr(struct dentry *dentry, struct iattr *attr, int err; bool trust_local_cmtime = is_wb && S_ISREG(inode->i_mode); - if (!(fc->flags & FUSE_DEFAULT_PERMISSIONS)) + if (!fc->default_permissions) attr->ia_valid |= ATTR_FORCE; err = setattr_prepare(dentry, attr); @@ -1703,172 +1716,75 @@ error: static int fuse_setattr(struct dentry *entry, struct iattr *attr) { struct inode *inode = d_inode(entry); - - if (!fuse_allow_current_process(get_fuse_conn(inode))) - return -EACCES; - - if (attr->ia_valid & ATTR_FILE) - return fuse_do_setattr(entry, attr, attr->ia_file); - else - return fuse_do_setattr(entry, attr, NULL); -} - -static int fuse_getattr(struct vfsmount *mnt, struct dentry *entry, - struct kstat *stat) -{ - struct inode *inode = d_inode(entry); struct fuse_conn *fc = get_fuse_conn(inode); + struct file *file = (attr->ia_valid & ATTR_FILE) ? attr->ia_file : NULL; + int ret; - if (!fuse_allow_current_process(fc)) + if (!fuse_allow_current_process(get_fuse_conn(inode))) return -EACCES; - return fuse_update_attributes(inode, stat, NULL, NULL); -} - -static int fuse_setxattr(struct dentry *unused, 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); - struct fuse_setxattr_in inarg; - int err; - - if (fc->no_setxattr) - return -EOPNOTSUPP; + if (attr->ia_valid & (ATTR_KILL_SUID | ATTR_KILL_SGID)) { + attr->ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | + ATTR_MODE); - memset(&inarg, 0, sizeof(inarg)); - inarg.size = size; - inarg.flags = flags; - args.in.h.opcode = FUSE_SETXATTR; - args.in.h.nodeid = get_node_id(inode); - args.in.numargs = 3; - args.in.args[0].size = sizeof(inarg); - args.in.args[0].value = &inarg; - args.in.args[1].size = strlen(name) + 1; - args.in.args[1].value = name; - args.in.args[2].size = size; - args.in.args[2].value = value; - err = fuse_simple_request(fc, &args); - if (err == -ENOSYS) { - fc->no_setxattr = 1; - err = -EOPNOTSUPP; - } - if (!err) { - fuse_invalidate_attr(inode); - fuse_update_ctime(inode); + /* + * The only sane way to reliably kill suid/sgid is to do it in + * the userspace filesystem + * + * This should be done on write(), truncate() and chown(). + */ + if (!fc->handle_killpriv) { + int kill; + + /* + * ia_mode calculation may have used stale i_mode. + * Refresh and recalculate. + */ + ret = fuse_do_getattr(inode, NULL, file); + if (ret) + return ret; + + attr->ia_mode = inode->i_mode; + kill = should_remove_suid(entry); + if (kill & ATTR_KILL_SUID) { + attr->ia_valid |= ATTR_MODE; + attr->ia_mode &= ~S_ISUID; + } + if (kill & ATTR_KILL_SGID) { + attr->ia_valid |= ATTR_MODE; + attr->ia_mode &= ~S_ISGID; + } + } } - return err; -} - -static ssize_t fuse_getxattr(struct dentry *entry, struct inode *inode, - const char *name, void *value, size_t size) -{ - struct fuse_conn *fc = get_fuse_conn(inode); - FUSE_ARGS(args); - struct fuse_getxattr_in inarg; - struct fuse_getxattr_out outarg; - ssize_t ret; + if (!attr->ia_valid) + return 0; - if (fc->no_getxattr) - return -EOPNOTSUPP; + ret = fuse_do_setattr(entry, 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); - memset(&inarg, 0, sizeof(inarg)); - inarg.size = size; - args.in.h.opcode = FUSE_GETXATTR; - args.in.h.nodeid = get_node_id(inode); - args.in.numargs = 2; - args.in.args[0].size = sizeof(inarg); - args.in.args[0].value = &inarg; - args.in.args[1].size = strlen(name) + 1; - args.in.args[1].value = name; - /* This is really two different operations rolled into one */ - args.out.numargs = 1; - if (size) { - args.out.argvar = 1; - args.out.args[0].size = size; - args.out.args[0].value = value; - } else { - args.out.args[0].size = sizeof(outarg); - args.out.args[0].value = &outarg; - } - ret = fuse_simple_request(fc, &args); - if (!ret && !size) - ret = outarg.size; - if (ret == -ENOSYS) { - fc->no_getxattr = 1; - ret = -EOPNOTSUPP; + /* Directory mode changed, may need to revalidate access */ + if (d_is_dir(entry) && (attr->ia_valid & ATTR_MODE)) + fuse_invalidate_entry_cache(entry); } return ret; } -static ssize_t fuse_listxattr(struct dentry *entry, char *list, size_t size) +static int fuse_getattr(struct vfsmount *mnt, struct dentry *entry, + struct kstat *stat) { struct inode *inode = d_inode(entry); struct fuse_conn *fc = get_fuse_conn(inode); - FUSE_ARGS(args); - struct fuse_getxattr_in inarg; - struct fuse_getxattr_out outarg; - ssize_t ret; if (!fuse_allow_current_process(fc)) return -EACCES; - if (fc->no_listxattr) - return -EOPNOTSUPP; - - memset(&inarg, 0, sizeof(inarg)); - inarg.size = size; - args.in.h.opcode = FUSE_LISTXATTR; - args.in.h.nodeid = get_node_id(inode); - args.in.numargs = 1; - args.in.args[0].size = sizeof(inarg); - args.in.args[0].value = &inarg; - /* This is really two different operations rolled into one */ - args.out.numargs = 1; - if (size) { - args.out.argvar = 1; - args.out.args[0].size = size; - args.out.args[0].value = list; - } else { - args.out.args[0].size = sizeof(outarg); - args.out.args[0].value = &outarg; - } - ret = fuse_simple_request(fc, &args); - if (!ret && !size) - ret = outarg.size; - if (ret == -ENOSYS) { - fc->no_listxattr = 1; - ret = -EOPNOTSUPP; - } - return ret; -} - -static int fuse_removexattr(struct dentry *entry, const char *name) -{ - struct inode *inode = d_inode(entry); - struct fuse_conn *fc = get_fuse_conn(inode); - FUSE_ARGS(args); - int err; - - if (fc->no_removexattr) - return -EOPNOTSUPP; - - args.in.h.opcode = FUSE_REMOVEXATTR; - args.in.h.nodeid = get_node_id(inode); - args.in.numargs = 1; - args.in.args[0].size = strlen(name) + 1; - args.in.args[0].value = name; - err = fuse_simple_request(fc, &args); - if (err == -ENOSYS) { - fc->no_removexattr = 1; - err = -EOPNOTSUPP; - } - if (!err) { - fuse_invalidate_attr(inode); - fuse_update_ctime(inode); - } - return err; + return fuse_update_attributes(inode, stat, NULL, NULL); } static const struct inode_operations fuse_dir_inode_operations = { @@ -1885,10 +1801,12 @@ static const struct inode_operations fuse_dir_inode_operations = { .mknod = fuse_mknod, .permission = fuse_permission, .getattr = fuse_getattr, - .setxattr = fuse_setxattr, - .getxattr = fuse_getxattr, + .setxattr = generic_setxattr, + .getxattr = generic_getxattr, .listxattr = fuse_listxattr, - .removexattr = fuse_removexattr, + .removexattr = generic_removexattr, + .get_acl = fuse_get_acl, + .set_acl = fuse_set_acl, }; static const struct file_operations fuse_dir_operations = { @@ -1906,10 +1824,12 @@ static const struct inode_operations fuse_common_inode_operations = { .setattr = fuse_setattr, .permission = fuse_permission, .getattr = fuse_getattr, - .setxattr = fuse_setxattr, - .getxattr = fuse_getxattr, + .setxattr = generic_setxattr, + .getxattr = generic_getxattr, .listxattr = fuse_listxattr, - .removexattr = fuse_removexattr, + .removexattr = generic_removexattr, + .get_acl = fuse_get_acl, + .set_acl = fuse_set_acl, }; static const struct inode_operations fuse_symlink_inode_operations = { @@ -1917,10 +1837,10 @@ static const struct inode_operations fuse_symlink_inode_operations = { .get_link = fuse_get_link, .readlink = generic_readlink, .getattr = fuse_getattr, - .setxattr = fuse_setxattr, - .getxattr = fuse_getxattr, + .setxattr = generic_setxattr, + .getxattr = generic_getxattr, .listxattr = fuse_listxattr, - .removexattr = fuse_removexattr, + .removexattr = generic_removexattr, }; void fuse_init_common(struct inode *inode) diff --git a/fs/fuse/file.c b/fs/fuse/file.c index 118bcb192a7b..abc66a6237fd 100644 --- a/fs/fuse/file.c +++ b/fs/fuse/file.c @@ -2326,49 +2326,6 @@ static loff_t fuse_file_llseek(struct file *file, loff_t offset, int whence) return retval; } -static int fuse_ioctl_copy_user(struct page **pages, struct iovec *iov, - unsigned int nr_segs, size_t bytes, bool to_user) -{ - struct iov_iter ii; - int page_idx = 0; - - if (!bytes) - return 0; - - iov_iter_init(&ii, to_user ? READ : WRITE, iov, nr_segs, bytes); - - while (iov_iter_count(&ii)) { - struct page *page = pages[page_idx++]; - size_t todo = min_t(size_t, PAGE_SIZE, iov_iter_count(&ii)); - void *kaddr; - - kaddr = kmap(page); - - while (todo) { - char __user *uaddr = ii.iov->iov_base + ii.iov_offset; - size_t iov_len = ii.iov->iov_len - ii.iov_offset; - size_t copy = min(todo, iov_len); - size_t left; - - if (!to_user) - left = copy_from_user(kaddr, uaddr, copy); - else - left = copy_to_user(uaddr, kaddr, copy); - - if (unlikely(left)) - return -EFAULT; - - iov_iter_advance(&ii, copy); - todo -= copy; - kaddr += copy; - } - - kunmap(page); - } - - return 0; -} - /* * CUSE servers compiled on 32bit broke on 64bit kernels because the * ABI was defined to be 'struct iovec' which is different on 32bit @@ -2520,8 +2477,9 @@ long fuse_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg, struct iovec *iov_page = NULL; struct iovec *in_iov = NULL, *out_iov = NULL; unsigned int in_iovs = 0, out_iovs = 0, num_pages = 0, max_pages; - size_t in_size, out_size, transferred; - int err; + size_t in_size, out_size, transferred, c; + int err, i; + struct iov_iter ii; #if BITS_PER_LONG == 32 inarg.flags |= FUSE_IOCTL_32BIT; @@ -2603,10 +2561,13 @@ long fuse_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg, req->in.args[1].size = in_size; req->in.argpages = 1; - err = fuse_ioctl_copy_user(pages, in_iov, in_iovs, in_size, - false); - if (err) - goto out; + err = -EFAULT; + iov_iter_init(&ii, WRITE, in_iov, in_iovs, in_size); + for (i = 0; iov_iter_count(&ii) && !WARN_ON(i >= num_pages); i++) { + c = copy_page_from_iter(pages[i], 0, PAGE_SIZE, &ii); + if (c != PAGE_SIZE && iov_iter_count(&ii)) + goto out; + } } req->out.numargs = 2; @@ -2672,7 +2633,14 @@ long fuse_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg, if (transferred > inarg.out_size) goto out; - err = fuse_ioctl_copy_user(pages, out_iov, out_iovs, transferred, true); + err = -EFAULT; + iov_iter_init(&ii, READ, out_iov, out_iovs, transferred); + for (i = 0; iov_iter_count(&ii) && !WARN_ON(i >= num_pages); i++) { + c = copy_page_to_iter(pages[i], 0, PAGE_SIZE, &ii); + if (c != PAGE_SIZE && iov_iter_count(&ii)) + goto out; + } + err = 0; out: if (req) fuse_put_request(fc, req); diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h index cace5526c6d6..0dfbb136e59a 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 @@ -36,15 +37,6 @@ /** Number of dentries for each connection in the control filesystem */ #define FUSE_CTL_NUM_DENTRIES 5 -/** If the FUSE_DEFAULT_PERMISSIONS flag is given, the filesystem - module will check permissions based on the file mode. Otherwise no - permission checking is done in the kernel */ -#define FUSE_DEFAULT_PERMISSIONS (1 << 0) - -/** If the FUSE_ALLOW_OTHER flag is given, then not only the user - doing the mount will be allowed to access the filesystem */ -#define FUSE_ALLOW_OTHER (1 << 1) - /** Number of page pointers embedded in fuse_req */ #define FUSE_REQ_INLINE_PAGES 1 @@ -469,9 +461,6 @@ struct fuse_conn { /** The group id for this mount */ kgid_t group_id; - /** The fuse mount flags for this mount */ - unsigned flags; - /** Maximum read size */ unsigned max_read; @@ -547,6 +536,9 @@ struct fuse_conn { /** allow parallel lookups and readdir (default is serialized) */ unsigned parallel_dirops:1; + /** handle fs handles killing suid/sgid/cap on write/chown/trunc */ + unsigned handle_killpriv:1; + /* * The following bitfields are only for optimization purposes * and hence races in setting them will not cause malfunction @@ -624,6 +616,15 @@ struct fuse_conn { /** Is lseek not implemented by fs? */ unsigned no_lseek:1; + /** Does the filesystem support posix acls? */ + unsigned posix_acl:1; + + /** Check permissions based on the file mode or not? */ + unsigned default_permissions:1; + + /** Allow other than the mounter user to access the filesystem ? */ + unsigned allow_other:1; + /** The number of requests waiting for completion */ atomic_t num_waiting; @@ -902,6 +903,8 @@ int fuse_allow_current_process(struct fuse_conn *fc); u64 fuse_lock_owner_id(struct fuse_conn *fc, fl_owner_t id); +void fuse_update_ctime(struct inode *inode); + int fuse_update_attributes(struct inode *inode, struct kstat *stat, struct file *file, bool *refreshed); @@ -966,4 +969,17 @@ 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 4e05b51120f4..17141099f2e7 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"); @@ -66,7 +67,8 @@ struct fuse_mount_data { unsigned rootmode_present:1; unsigned user_id_present:1; unsigned group_id_present:1; - unsigned flags; + unsigned default_permissions:1; + unsigned allow_other:1; unsigned max_read; unsigned blksize; }; @@ -192,7 +194,7 @@ void fuse_change_attributes_common(struct inode *inode, struct fuse_attr *attr, * check in may_delete(). */ fi->orig_i_mode = inode->i_mode; - if (!(fc->flags & FUSE_DEFAULT_PERMISSIONS)) + if (!fc->default_permissions) inode->i_mode &= ~S_ISVTX; fi->orig_ino = attr->ino; @@ -340,6 +342,7 @@ 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) @@ -532,11 +535,11 @@ static int parse_fuse_opt(char *opt, struct fuse_mount_data *d, int is_bdev) break; case OPT_DEFAULT_PERMISSIONS: - d->flags |= FUSE_DEFAULT_PERMISSIONS; + d->default_permissions = 1; break; case OPT_ALLOW_OTHER: - d->flags |= FUSE_ALLOW_OTHER; + d->allow_other = 1; break; case OPT_MAX_READ: @@ -570,9 +573,9 @@ static int fuse_show_options(struct seq_file *m, struct dentry *root) seq_printf(m, ",user_id=%u", from_kuid_munged(&init_user_ns, fc->user_id)); seq_printf(m, ",group_id=%u", from_kgid_munged(&init_user_ns, fc->group_id)); - if (fc->flags & FUSE_DEFAULT_PERMISSIONS) + if (fc->default_permissions) seq_puts(m, ",default_permissions"); - if (fc->flags & FUSE_ALLOW_OTHER) + if (fc->allow_other) seq_puts(m, ",allow_other"); if (fc->max_read != ~0) seq_printf(m, ",max_read=%u", fc->max_read); @@ -910,8 +913,15 @@ static void process_init_reply(struct fuse_conn *fc, struct fuse_req *req) fc->writeback_cache = 1; if (arg->flags & FUSE_PARALLEL_DIROPS) fc->parallel_dirops = 1; + if (arg->flags & FUSE_HANDLE_KILLPRIV) + 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->default_permissions = 1; + fc->posix_acl = 1; + fc->sb->s_xattr = fuse_acl_xattr_handlers; + } } else { ra_pages = fc->max_read / PAGE_SIZE; fc->no_lock = 1; @@ -941,7 +951,7 @@ 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_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); @@ -1071,6 +1081,7 @@ static int fuse_fill_super(struct super_block *sb, void *data, int silent) } sb->s_magic = FUSE_SUPER_MAGIC; sb->s_op = &fuse_super_operations; + sb->s_xattr = fuse_xattr_handlers; sb->s_maxbytes = MAX_LFS_FILESIZE; sb->s_time_gran = 1; sb->s_export_op = &fuse_export_operations; @@ -1109,7 +1120,8 @@ static int fuse_fill_super(struct super_block *sb, void *data, int silent) fc->dont_mask = 1; sb->s_flags |= MS_POSIXACL; - fc->flags = d.flags; + fc->default_permissions = d.default_permissions; + fc->allow_other = d.allow_other; fc->user_id = d.user_id; fc->group_id = d.group_id; fc->max_read = max_t(unsigned, 4096, d.max_read); diff --git a/fs/fuse/xattr.c b/fs/fuse/xattr.c new file mode 100644 index 000000000000..3caac46b08b0 --- /dev/null +++ b/fs/fuse/xattr.c @@ -0,0 +1,211 @@ +/* + * FUSE: Filesystem in Userspace + * Copyright (C) 2001-2016 Miklos Szeredi <miklos@szeredi.hu> + * + * This program can be distributed under the terms of the GNU GPL. + * See the file COPYING. + */ + +#include "fuse_i.h" + +#include <linux/xattr.h> +#include <linux/posix_acl_xattr.h> + +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); + struct fuse_setxattr_in inarg; + int err; + + if (fc->no_setxattr) + return -EOPNOTSUPP; + + memset(&inarg, 0, sizeof(inarg)); + inarg.size = size; + inarg.flags = flags; + args.in.h.opcode = FUSE_SETXATTR; + args.in.h.nodeid = get_node_id(inode); + args.in.numargs = 3; + args.in.args[0].size = sizeof(inarg); + args.in.args[0].value = &inarg; + args.in.args[1].size = strlen(name) + 1; + args.in.args[1].value = name; + args.in.args[2].size = size; + args.in.args[2].value = value; + err = fuse_simple_request(fc, &args); + if (err == -ENOSYS) { + fc->no_setxattr = 1; + err = -EOPNOTSUPP; + } + if (!err) { + fuse_invalidate_attr(inode); + fuse_update_ctime(inode); + } + return err; +} + +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); + struct fuse_getxattr_in inarg; + struct fuse_getxattr_out outarg; + ssize_t ret; + + if (fc->no_getxattr) + return -EOPNOTSUPP; + + memset(&inarg, 0, sizeof(inarg)); + inarg.size = size; + args.in.h.opcode = FUSE_GETXATTR; + args.in.h.nodeid = get_node_id(inode); + args.in.numargs = 2; + args.in.args[0].size = sizeof(inarg); + args.in.args[0].value = &inarg; + args.in.args[1].size = strlen(name) + 1; + args.in.args[1].value = name; + /* This is really two different operations rolled into one */ + args.out.numargs = 1; + if (size) { + args.out.argvar = 1; + args.out.args[0].size = size; + args.out.args[0].value = value; + } else { + args.out.args[0].size = sizeof(outarg); + args.out.args[0].value = &outarg; + } + ret = fuse_simple_request(fc, &args); + if (!ret && !size) + ret = min_t(ssize_t, outarg.size, XATTR_SIZE_MAX); + if (ret == -ENOSYS) { + fc->no_getxattr = 1; + ret = -EOPNOTSUPP; + } + return ret; +} + +static int fuse_verify_xattr_list(char *list, size_t size) +{ + size_t origsize = size; + + while (size) { + size_t thislen = strnlen(list, size); + + if (!thislen || thislen == size) + return -EIO; + + size -= thislen + 1; + list += thislen + 1; + } + + return origsize; +} + +ssize_t fuse_listxattr(struct dentry *entry, char *list, size_t size) +{ + struct inode *inode = d_inode(entry); + struct fuse_conn *fc = get_fuse_conn(inode); + FUSE_ARGS(args); + struct fuse_getxattr_in inarg; + struct fuse_getxattr_out outarg; + ssize_t ret; + + if (!fuse_allow_current_process(fc)) + return -EACCES; + + if (fc->no_listxattr) + return -EOPNOTSUPP; + + memset(&inarg, 0, sizeof(inarg)); + inarg.size = size; + args.in.h.opcode = FUSE_LISTXATTR; + args.in.h.nodeid = get_node_id(inode); + args.in.numargs = 1; + args.in.args[0].size = sizeof(inarg); + args.in.args[0].value = &inarg; + /* This is really two different operations rolled into one */ + args.out.numargs = 1; + if (size) { + args.out.argvar = 1; + args.out.args[0].size = size; + args.out.args[0].value = list; + } else { + args.out.args[0].size = sizeof(outarg); + args.out.args[0].value = &outarg; + } + ret = fuse_simple_request(fc, &args); + if (!ret && !size) + ret = min_t(ssize_t, outarg.size, XATTR_LIST_MAX); + if (ret > 0 && size) + ret = fuse_verify_xattr_list(list, ret); + if (ret == -ENOSYS) { + fc->no_listxattr = 1; + ret = -EOPNOTSUPP; + } + return ret; +} + +int fuse_removexattr(struct inode *inode, const char *name) +{ + struct fuse_conn *fc = get_fuse_conn(inode); + FUSE_ARGS(args); + int err; + + if (fc->no_removexattr) + return -EOPNOTSUPP; + + args.in.h.opcode = FUSE_REMOVEXATTR; + args.in.h.nodeid = get_node_id(inode); + args.in.numargs = 1; + args.in.args[0].size = strlen(name) + 1; + args.in.args[0].value = name; + err = fuse_simple_request(fc, &args); + if (err == -ENOSYS) { + fc->no_removexattr = 1; + err = -EOPNOTSUPP; + } + if (!err) { + fuse_invalidate_attr(inode); + fuse_update_ctime(inode); + } + return err; +} + +static int fuse_xattr_get(const struct xattr_handler *handler, + struct dentry *dentry, struct inode *inode, + const char *name, void *value, size_t size) +{ + return fuse_getxattr(inode, name, value, size); +} + +static int fuse_xattr_set(const struct xattr_handler *handler, + struct dentry *dentry, struct inode *inode, + const char *name, const void *value, size_t size, + int flags) +{ + if (!value) + return fuse_removexattr(inode, name); + + return fuse_setxattr(inode, name, value, size, flags); +} + +static const struct xattr_handler fuse_xattr_handler = { + .prefix = "", + .get = fuse_xattr_get, + .set = fuse_xattr_set, +}; + +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 +}; |