diff options
Diffstat (limited to 'fs/posix_acl.c')
| -rw-r--r-- | fs/posix_acl.c | 198 |
1 files changed, 114 insertions, 84 deletions
diff --git a/fs/posix_acl.c b/fs/posix_acl.c index d7bc81fc0840..768f027c1428 100644 --- a/fs/posix_acl.c +++ b/fs/posix_acl.c @@ -26,8 +26,8 @@ #include <linux/mnt_idmapping.h> #include <linux/iversion.h> #include <linux/security.h> -#include <linux/evm.h> #include <linux/fsnotify.h> +#include <linux/filelock.h> #include "internal.h" @@ -111,7 +111,7 @@ void forget_all_cached_acls(struct inode *inode) } EXPORT_SYMBOL(forget_all_cached_acls); -static struct posix_acl *__get_acl(struct user_namespace *mnt_userns, +static struct posix_acl *__get_acl(struct mnt_idmap *idmap, struct dentry *dentry, struct inode *inode, int type) { @@ -154,7 +154,7 @@ static struct posix_acl *__get_acl(struct user_namespace *mnt_userns, * we'll just create the negative cache entry. */ if (dentry && inode->i_op->get_acl) { - acl = inode->i_op->get_acl(mnt_userns, dentry, type); + acl = inode->i_op->get_acl(idmap, dentry, type); } else if (inode->i_op->get_inode_acl) { acl = inode->i_op->get_inode_acl(inode, type, false); } else { @@ -174,14 +174,14 @@ static struct posix_acl *__get_acl(struct user_namespace *mnt_userns, * Cache the result, but only if our sentinel is still in place. */ posix_acl_dup(acl); - if (unlikely(cmpxchg(p, sentinel, acl) != sentinel)) + if (unlikely(!try_cmpxchg(p, &sentinel, acl))) posix_acl_release(acl); return acl; } struct posix_acl *get_inode_acl(struct inode *inode, int type) { - return __get_acl(&init_user_ns, NULL, inode, type); + return __get_acl(&nop_mnt_idmap, NULL, inode, type); } EXPORT_SYMBOL(get_inode_acl); @@ -200,11 +200,11 @@ EXPORT_SYMBOL(posix_acl_init); * Allocate a new ACL with the specified number of entries. */ struct posix_acl * -posix_acl_alloc(int count, gfp_t flags) +posix_acl_alloc(unsigned int count, gfp_t flags) { - const size_t size = sizeof(struct posix_acl) + - count * sizeof(struct posix_acl_entry); - struct posix_acl *acl = kmalloc(size, flags); + struct posix_acl *acl; + + acl = kmalloc(struct_size(acl, a_entries, count), flags); if (acl) posix_acl_init(acl, count); return acl; @@ -220,9 +220,8 @@ posix_acl_clone(const struct posix_acl *acl, gfp_t flags) struct posix_acl *clone = NULL; if (acl) { - int size = sizeof(struct posix_acl) + acl->a_count * - sizeof(struct posix_acl_entry); - clone = kmemdup(acl, size, flags); + clone = kmemdup(acl, struct_size(acl, a_entries, acl->a_count), + flags); if (clone) refcount_set(&clone->a_refcount, 1); } @@ -372,7 +371,7 @@ EXPORT_SYMBOL(posix_acl_from_mode); * by the acl. Returns -E... otherwise. */ int -posix_acl_permission(struct user_namespace *mnt_userns, struct inode *inode, +posix_acl_permission(struct mnt_idmap *idmap, struct inode *inode, const struct posix_acl *acl, int want) { const struct posix_acl_entry *pa, *pe, *mask_obj; @@ -387,18 +386,18 @@ posix_acl_permission(struct user_namespace *mnt_userns, struct inode *inode, switch(pa->e_tag) { case ACL_USER_OBJ: /* (May have been checked already) */ - vfsuid = i_uid_into_vfsuid(mnt_userns, inode); + vfsuid = i_uid_into_vfsuid(idmap, inode); if (vfsuid_eq_kuid(vfsuid, current_fsuid())) goto check_perm; break; case ACL_USER: - vfsuid = make_vfsuid(mnt_userns, fs_userns, + vfsuid = make_vfsuid(idmap, fs_userns, pa->e_uid); if (vfsuid_eq_kuid(vfsuid, current_fsuid())) goto mask; break; case ACL_GROUP_OBJ: - vfsgid = i_gid_into_vfsgid(mnt_userns, inode); + vfsgid = i_gid_into_vfsgid(idmap, inode); if (vfsgid_in_group_p(vfsgid)) { found = 1; if ((pa->e_perm & want) == want) @@ -406,7 +405,7 @@ posix_acl_permission(struct user_namespace *mnt_userns, struct inode *inode, } break; case ACL_GROUP: - vfsgid = make_vfsgid(mnt_userns, fs_userns, + vfsgid = make_vfsgid(idmap, fs_userns, pa->e_gid); if (vfsgid_in_group_p(vfsgid)) { found = 1; @@ -591,18 +590,18 @@ EXPORT_SYMBOL(__posix_acl_chmod); /** * posix_acl_chmod - chmod a posix acl * - * @mnt_userns: user namespace of the mount @inode was found from + * @idmap: idmap of the mount @inode was found from * @dentry: dentry to check permissions on * @mode: the new mode of @inode * - * If the dentry 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 + * If the dentry has been found through an idmapped mount the idmap of + * the vfsmount must be passed through @idmap. This function will then + * take care to map the inode according to @idmap before checking * permissions. On non-idmapped mounts or if permission checking is to be - * performed on the raw inode simply passs init_user_ns. + * performed on the raw inode simply pass @nop_mnt_idmap. */ int - posix_acl_chmod(struct user_namespace *mnt_userns, struct dentry *dentry, + posix_acl_chmod(struct mnt_idmap *idmap, struct dentry *dentry, umode_t mode) { struct inode *inode = d_inode(dentry); @@ -624,7 +623,7 @@ int ret = __posix_acl_chmod(&acl, GFP_KERNEL, mode); if (ret) return ret; - ret = inode->i_op->set_acl(mnt_userns, dentry, acl, ACL_TYPE_ACCESS); + ret = inode->i_op->set_acl(idmap, dentry, acl, ACL_TYPE_ACCESS); posix_acl_release(acl); return ret; } @@ -683,7 +682,7 @@ EXPORT_SYMBOL_GPL(posix_acl_create); /** * posix_acl_update_mode - update mode in set_acl - * @mnt_userns: user namespace of the mount @inode was found from + * @idmap: idmap of the mount @inode was found from * @inode: target inode * @mode_p: mode (pointer) for update * @acl: acl pointer @@ -695,15 +694,15 @@ EXPORT_SYMBOL_GPL(posix_acl_create); * As with chmod, clear the setgid bit if the caller is not in the owning group * or capable of CAP_FSETID (see inode_change_ok). * - * 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 + * If the inode has been found through an idmapped mount the idmap of + * the vfsmount must be passed through @idmap. This function will then + * take care to map the inode according to @idmap before checking * permissions. On non-idmapped mounts or if permission checking is to be - * performed on the raw inode simply passs init_user_ns. + * performed on the raw inode simply pass @nop_mnt_idmap. * * Called from set_acl inode operations. */ -int posix_acl_update_mode(struct user_namespace *mnt_userns, +int posix_acl_update_mode(struct mnt_idmap *idmap, struct inode *inode, umode_t *mode_p, struct posix_acl **acl) { @@ -715,8 +714,8 @@ int posix_acl_update_mode(struct user_namespace *mnt_userns, return error; if (error == 0) *acl = NULL; - if (!vfsgid_in_group_p(i_gid_into_vfsgid(mnt_userns, inode)) && - !capable_wrt_inode_uidgid(mnt_userns, inode, CAP_FSETID)) + if (!in_group_or_capable(idmap, inode, + i_gid_into_vfsgid(idmap, inode))) mode &= ~S_ISGID; *mode_p = mode; return 0; @@ -785,12 +784,12 @@ struct posix_acl *posix_acl_from_xattr(struct user_namespace *userns, return ERR_PTR(count); if (count == 0) return NULL; - + acl = posix_acl_alloc(count, GFP_NOFS); if (!acl) return ERR_PTR(-ENOMEM); acl_e = acl->a_entries; - + for (end = entry + count; entry != end; acl_e++, entry++) { acl_e->e_tag = le16_to_cpu(entry->e_tag); acl_e->e_perm = le16_to_cpu(entry->e_perm); @@ -893,7 +892,6 @@ static ssize_t vfs_posix_acl_to_xattr(struct mnt_idmap *idmap, struct posix_acl_xattr_header *ext_acl = buffer; struct posix_acl_xattr_entry *ext_entry; struct user_namespace *fs_userns, *caller_userns; - struct user_namespace *mnt_userns; ssize_t real_size, n; vfsuid_t vfsuid; vfsgid_t vfsgid; @@ -909,19 +907,18 @@ static ssize_t vfs_posix_acl_to_xattr(struct mnt_idmap *idmap, fs_userns = i_user_ns(inode); caller_userns = current_user_ns(); - mnt_userns = mnt_idmap_owner(idmap); for (n=0; n < acl->a_count; n++, ext_entry++) { const struct posix_acl_entry *acl_e = &acl->a_entries[n]; ext_entry->e_tag = cpu_to_le16(acl_e->e_tag); ext_entry->e_perm = cpu_to_le16(acl_e->e_perm); switch(acl_e->e_tag) { case ACL_USER: - vfsuid = make_vfsuid(mnt_userns, fs_userns, acl_e->e_uid); + vfsuid = make_vfsuid(idmap, fs_userns, acl_e->e_uid); ext_entry->e_id = cpu_to_le32(from_kuid( caller_userns, vfsuid_into_kuid(vfsuid))); break; case ACL_GROUP: - vfsgid = make_vfsgid(mnt_userns, fs_userns, acl_e->e_gid); + vfsgid = make_vfsgid(idmap, fs_userns, acl_e->e_gid); ext_entry->e_id = cpu_to_le32(from_kgid( caller_userns, vfsgid_into_kgid(vfsgid))); break; @@ -934,7 +931,7 @@ static ssize_t vfs_posix_acl_to_xattr(struct mnt_idmap *idmap, } int -set_posix_acl(struct user_namespace *mnt_userns, struct dentry *dentry, +set_posix_acl(struct mnt_idmap *idmap, struct dentry *dentry, int type, struct posix_acl *acl) { struct inode *inode = d_inode(dentry); @@ -946,7 +943,7 @@ set_posix_acl(struct user_namespace *mnt_userns, struct dentry *dentry, if (type == ACL_TYPE_DEFAULT && !S_ISDIR(inode->i_mode)) return acl ? -EACCES : 0; - if (!inode_owner_or_capable(mnt_userns, inode)) + if (!inode_owner_or_capable(idmap, inode)) return -EPERM; if (acl) { @@ -954,44 +951,81 @@ set_posix_acl(struct user_namespace *mnt_userns, struct dentry *dentry, if (ret) return ret; } - return inode->i_op->set_acl(mnt_userns, dentry, acl, type); + return inode->i_op->set_acl(idmap, dentry, acl, type); } EXPORT_SYMBOL(set_posix_acl); +int posix_acl_listxattr(struct inode *inode, char **buffer, + ssize_t *remaining_size) +{ + int err; + + if (!IS_POSIXACL(inode)) + return 0; + + if (inode->i_acl) { + err = xattr_list_one(buffer, remaining_size, + XATTR_NAME_POSIX_ACL_ACCESS); + if (err) + return err; + } + + if (inode->i_default_acl) { + err = xattr_list_one(buffer, remaining_size, + XATTR_NAME_POSIX_ACL_DEFAULT); + if (err) + return err; + } + + return 0; +} + static bool posix_acl_xattr_list(struct dentry *dentry) { return IS_POSIXACL(d_backing_inode(dentry)); } -const struct xattr_handler posix_acl_access_xattr_handler = { +/* + * nop_posix_acl_access - legacy xattr handler for access POSIX ACLs + * + * This is the legacy POSIX ACL access xattr handler. It is used by some + * filesystems to implement their ->listxattr() inode operation. New code + * should never use them. + */ +const struct xattr_handler nop_posix_acl_access = { .name = XATTR_NAME_POSIX_ACL_ACCESS, - .flags = ACL_TYPE_ACCESS, .list = posix_acl_xattr_list, }; -EXPORT_SYMBOL_GPL(posix_acl_access_xattr_handler); +EXPORT_SYMBOL_GPL(nop_posix_acl_access); -const struct xattr_handler posix_acl_default_xattr_handler = { +/* + * nop_posix_acl_default - legacy xattr handler for default POSIX ACLs + * + * This is the legacy POSIX ACL default xattr handler. It is used by some + * filesystems to implement their ->listxattr() inode operation. New code + * should never use them. + */ +const struct xattr_handler nop_posix_acl_default = { .name = XATTR_NAME_POSIX_ACL_DEFAULT, - .flags = ACL_TYPE_DEFAULT, .list = posix_acl_xattr_list, }; -EXPORT_SYMBOL_GPL(posix_acl_default_xattr_handler); +EXPORT_SYMBOL_GPL(nop_posix_acl_default); -int simple_set_acl(struct user_namespace *mnt_userns, struct dentry *dentry, +int simple_set_acl(struct mnt_idmap *idmap, struct dentry *dentry, struct posix_acl *acl, int type) { int error; struct inode *inode = d_inode(dentry); if (type == ACL_TYPE_ACCESS) { - error = posix_acl_update_mode(mnt_userns, inode, + error = posix_acl_update_mode(idmap, inode, &inode->i_mode, &acl); if (error) return error; } - inode->i_ctime = current_time(inode); + inode_set_ctime_current(inode); if (IS_I_VERSION(inode)) inode_inc_iversion(inode); set_cached_acl(inode, type, acl); @@ -1017,7 +1051,7 @@ int simple_acl_create(struct inode *dir, struct inode *inode) return 0; } -static int vfs_set_acl_idmapped_mnt(struct user_namespace *mnt_userns, +static int vfs_set_acl_idmapped_mnt(struct mnt_idmap *idmap, struct user_namespace *fs_userns, struct posix_acl *acl) { @@ -1026,11 +1060,11 @@ static int vfs_set_acl_idmapped_mnt(struct user_namespace *mnt_userns, switch (acl_e->e_tag) { case ACL_USER: - acl_e->e_uid = from_vfsuid(mnt_userns, fs_userns, + acl_e->e_uid = from_vfsuid(idmap, fs_userns, VFSUIDT_INIT(acl_e->e_uid)); break; case ACL_GROUP: - acl_e->e_gid = from_vfsgid(mnt_userns, fs_userns, + acl_e->e_gid = from_vfsgid(idmap, fs_userns, VFSGIDT_INIT(acl_e->e_gid)); break; } @@ -1041,7 +1075,7 @@ static int vfs_set_acl_idmapped_mnt(struct user_namespace *mnt_userns, /** * vfs_set_acl - set posix acls - * @mnt_userns: user namespace of the mount + * @idmap: idmap of the mount * @dentry: the dentry based on which to set the posix acls * @acl_name: the name of the posix acl * @kacl: the posix acls in the appropriate VFS format @@ -1051,13 +1085,13 @@ static int vfs_set_acl_idmapped_mnt(struct user_namespace *mnt_userns, * * Return: On success 0, on error negative errno. */ -int vfs_set_acl(struct user_namespace *mnt_userns, struct dentry *dentry, +int vfs_set_acl(struct mnt_idmap *idmap, struct dentry *dentry, const char *acl_name, struct posix_acl *kacl) { int acl_type; int error; struct inode *inode = d_inode(dentry); - struct inode *delegated_inode = NULL; + struct delegated_inode delegated_inode = { }; acl_type = posix_acl_type(acl_name); if (acl_type < 0) @@ -1071,7 +1105,7 @@ int vfs_set_acl(struct user_namespace *mnt_userns, struct dentry *dentry, * if this is a filesystem with a backing store - ultimately * translate them to backing store values. */ - error = vfs_set_acl_idmapped_mnt(mnt_userns, i_user_ns(inode), kacl); + error = vfs_set_acl_idmapped_mnt(idmap, i_user_ns(inode), kacl); if (error) return error; } @@ -1083,11 +1117,11 @@ retry_deleg: * We only care about restrictions the inode struct itself places upon * us otherwise POSIX ACLs aren't subject to any VFS restrictions. */ - error = may_write_xattr(mnt_userns, inode); + error = may_write_xattr(idmap, inode); if (error) goto out_inode_unlock; - error = security_inode_set_acl(mnt_userns, dentry, acl_name, kacl); + error = security_inode_set_acl(idmap, dentry, acl_name, kacl); if (error) goto out_inode_unlock; @@ -1095,21 +1129,19 @@ retry_deleg: if (error) goto out_inode_unlock; - if (inode->i_opflags & IOP_XATTR) - error = set_posix_acl(mnt_userns, dentry, acl_type, kacl); - else if (unlikely(is_bad_inode(inode))) - error = -EIO; + if (likely(!is_bad_inode(inode))) + error = set_posix_acl(idmap, dentry, acl_type, kacl); else - error = -EOPNOTSUPP; + error = -EIO; if (!error) { fsnotify_xattr(dentry); - evm_inode_post_set_acl(dentry, acl_name, kacl); + security_inode_post_set_acl(dentry, acl_name, kacl); } out_inode_unlock: inode_unlock(inode); - if (delegated_inode) { + if (is_delegated(&delegated_inode)) { error = break_deleg_wait(&delegated_inode); if (!error) goto retry_deleg; @@ -1121,7 +1153,7 @@ EXPORT_SYMBOL_GPL(vfs_set_acl); /** * vfs_get_acl - get posix acls - * @mnt_userns: user namespace of the mount + * @idmap: idmap of the mount * @dentry: the dentry based on which to retrieve the posix acls * @acl_name: the name of the posix acl * @@ -1130,7 +1162,7 @@ EXPORT_SYMBOL_GPL(vfs_set_acl); * * Return: On success POSIX ACLs in VFS format, on error negative errno. */ -struct posix_acl *vfs_get_acl(struct user_namespace *mnt_userns, +struct posix_acl *vfs_get_acl(struct mnt_idmap *idmap, struct dentry *dentry, const char *acl_name) { struct inode *inode = d_inode(dentry); @@ -1145,7 +1177,7 @@ struct posix_acl *vfs_get_acl(struct user_namespace *mnt_userns, * The VFS has no restrictions on reading POSIX ACLs so calling * something like xattr_permission() isn't needed. Only LSMs get a say. */ - error = security_inode_get_acl(mnt_userns, dentry, acl_name); + error = security_inode_get_acl(idmap, dentry, acl_name); if (error) return ERR_PTR(error); @@ -1154,7 +1186,7 @@ struct posix_acl *vfs_get_acl(struct user_namespace *mnt_userns, if (S_ISLNK(inode->i_mode)) return ERR_PTR(-EOPNOTSUPP); - acl = __get_acl(mnt_userns, dentry, inode, acl_type); + acl = __get_acl(idmap, dentry, inode, acl_type); if (IS_ERR(acl)) return acl; if (!acl) @@ -1166,7 +1198,7 @@ EXPORT_SYMBOL_GPL(vfs_get_acl); /** * vfs_remove_acl - remove posix acls - * @mnt_userns: user namespace of the mount + * @idmap: idmap of the mount * @dentry: the dentry based on which to retrieve the posix acls * @acl_name: the name of the posix acl * @@ -1174,13 +1206,13 @@ EXPORT_SYMBOL_GPL(vfs_get_acl); * * Return: On success 0, on error negative errno. */ -int vfs_remove_acl(struct user_namespace *mnt_userns, struct dentry *dentry, +int vfs_remove_acl(struct mnt_idmap *idmap, struct dentry *dentry, const char *acl_name) { int acl_type; int error; struct inode *inode = d_inode(dentry); - struct inode *delegated_inode = NULL; + struct delegated_inode delegated_inode = { }; acl_type = posix_acl_type(acl_name); if (acl_type < 0) @@ -1193,11 +1225,11 @@ retry_deleg: * We only care about restrictions the inode struct itself places upon * us otherwise POSIX ACLs aren't subject to any VFS restrictions. */ - error = may_write_xattr(mnt_userns, inode); + error = may_write_xattr(idmap, inode); if (error) goto out_inode_unlock; - error = security_inode_remove_acl(mnt_userns, dentry, acl_name); + error = security_inode_remove_acl(idmap, dentry, acl_name); if (error) goto out_inode_unlock; @@ -1205,21 +1237,19 @@ retry_deleg: if (error) goto out_inode_unlock; - if (inode->i_opflags & IOP_XATTR) - error = set_posix_acl(mnt_userns, dentry, acl_type, NULL); - else if (unlikely(is_bad_inode(inode))) - error = -EIO; + if (likely(!is_bad_inode(inode))) + error = set_posix_acl(idmap, dentry, acl_type, NULL); else - error = -EOPNOTSUPP; + error = -EIO; if (!error) { fsnotify_xattr(dentry); - evm_inode_post_remove_acl(mnt_userns, dentry, acl_name); + security_inode_post_remove_acl(idmap, dentry, acl_name); } out_inode_unlock: inode_unlock(inode); - if (delegated_inode) { + if (is_delegated(&delegated_inode)) { error = break_deleg_wait(&delegated_inode); if (!error) goto retry_deleg; @@ -1245,7 +1275,7 @@ int do_set_acl(struct mnt_idmap *idmap, struct dentry *dentry, return PTR_ERR(acl); } - error = vfs_set_acl(mnt_idmap_owner(idmap), dentry, acl_name, acl); + error = vfs_set_acl(idmap, dentry, acl_name, acl); posix_acl_release(acl); return error; } @@ -1256,7 +1286,7 @@ ssize_t do_get_acl(struct mnt_idmap *idmap, struct dentry *dentry, ssize_t error; struct posix_acl *acl; - acl = vfs_get_acl(mnt_idmap_owner(idmap), dentry, acl_name); + acl = vfs_get_acl(idmap, dentry, acl_name); if (IS_ERR(acl)) return PTR_ERR(acl); |
