From 5c8ebd57b6a51daf53f75b7a16c45090a98a91a4 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Fri, 20 Dec 2013 05:16:37 -0800 Subject: fs: merge xattr_acl.c into posix_acl.c Signed-off-by: Christoph Hellwig Signed-off-by: Al Viro --- fs/posix_acl.c | 180 ++++++++++++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 173 insertions(+), 7 deletions(-) (limited to 'fs/posix_acl.c') diff --git a/fs/posix_acl.c b/fs/posix_acl.c index 8bd2135b7f82..359d70b0e947 100644 --- a/fs/posix_acl.c +++ b/fs/posix_acl.c @@ -1,10 +1,8 @@ /* - * linux/fs/posix_acl.c + * Copyright (C) 2002,2003 by Andreas Gruenbacher * - * Copyright (C) 2002 by Andreas Gruenbacher - * - * Fixes from William Schumacher incorporated on 15 March 2001. - * (Reported by Charles Bertsch, ). + * Fixes from William Schumacher incorporated on 15 March 2001. + * (Reported by Charles Bertsch, ). */ /* @@ -18,9 +16,9 @@ #include #include #include +#include #include - -#include +#include EXPORT_SYMBOL(posix_acl_init); EXPORT_SYMBOL(posix_acl_alloc); @@ -418,3 +416,171 @@ posix_acl_chmod(struct posix_acl **acl, gfp_t gfp, umode_t mode) return err; } EXPORT_SYMBOL(posix_acl_chmod); + +/* + * Fix up the uids and gids in posix acl extended attributes in place. + */ +static void posix_acl_fix_xattr_userns( + struct user_namespace *to, struct user_namespace *from, + void *value, size_t size) +{ + posix_acl_xattr_header *header = (posix_acl_xattr_header *)value; + posix_acl_xattr_entry *entry = (posix_acl_xattr_entry *)(header+1), *end; + int count; + kuid_t uid; + kgid_t gid; + + if (!value) + return; + if (size < sizeof(posix_acl_xattr_header)) + return; + if (header->a_version != cpu_to_le32(POSIX_ACL_XATTR_VERSION)) + return; + + count = posix_acl_xattr_count(size); + if (count < 0) + return; + if (count == 0) + return; + + for (end = entry + count; entry != end; entry++) { + switch(le16_to_cpu(entry->e_tag)) { + case ACL_USER: + uid = make_kuid(from, le32_to_cpu(entry->e_id)); + entry->e_id = cpu_to_le32(from_kuid(to, uid)); + break; + case ACL_GROUP: + gid = make_kgid(from, le32_to_cpu(entry->e_id)); + entry->e_id = cpu_to_le32(from_kgid(to, gid)); + break; + default: + break; + } + } +} + +void posix_acl_fix_xattr_from_user(void *value, size_t size) +{ + struct user_namespace *user_ns = current_user_ns(); + if (user_ns == &init_user_ns) + return; + posix_acl_fix_xattr_userns(&init_user_ns, user_ns, value, size); +} + +void posix_acl_fix_xattr_to_user(void *value, size_t size) +{ + struct user_namespace *user_ns = current_user_ns(); + if (user_ns == &init_user_ns) + return; + posix_acl_fix_xattr_userns(user_ns, &init_user_ns, value, size); +} + +/* + * Convert from extended attribute to in-memory representation. + */ +struct posix_acl * +posix_acl_from_xattr(struct user_namespace *user_ns, + const void *value, size_t size) +{ + posix_acl_xattr_header *header = (posix_acl_xattr_header *)value; + posix_acl_xattr_entry *entry = (posix_acl_xattr_entry *)(header+1), *end; + int count; + struct posix_acl *acl; + struct posix_acl_entry *acl_e; + + if (!value) + return NULL; + if (size < sizeof(posix_acl_xattr_header)) + return ERR_PTR(-EINVAL); + if (header->a_version != cpu_to_le32(POSIX_ACL_XATTR_VERSION)) + return ERR_PTR(-EOPNOTSUPP); + + count = posix_acl_xattr_count(size); + if (count < 0) + return ERR_PTR(-EINVAL); + 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); + + switch(acl_e->e_tag) { + case ACL_USER_OBJ: + case ACL_GROUP_OBJ: + case ACL_MASK: + case ACL_OTHER: + break; + + case ACL_USER: + acl_e->e_uid = + make_kuid(user_ns, + le32_to_cpu(entry->e_id)); + if (!uid_valid(acl_e->e_uid)) + goto fail; + break; + case ACL_GROUP: + acl_e->e_gid = + make_kgid(user_ns, + le32_to_cpu(entry->e_id)); + if (!gid_valid(acl_e->e_gid)) + goto fail; + break; + + default: + goto fail; + } + } + return acl; + +fail: + posix_acl_release(acl); + return ERR_PTR(-EINVAL); +} +EXPORT_SYMBOL (posix_acl_from_xattr); + +/* + * Convert from in-memory to extended attribute representation. + */ +int +posix_acl_to_xattr(struct user_namespace *user_ns, const struct posix_acl *acl, + void *buffer, size_t size) +{ + posix_acl_xattr_header *ext_acl = (posix_acl_xattr_header *)buffer; + posix_acl_xattr_entry *ext_entry = ext_acl->a_entries; + int real_size, n; + + real_size = posix_acl_xattr_size(acl->a_count); + if (!buffer) + return real_size; + if (real_size > size) + return -ERANGE; + + ext_acl->a_version = cpu_to_le32(POSIX_ACL_XATTR_VERSION); + + 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: + ext_entry->e_id = + cpu_to_le32(from_kuid(user_ns, acl_e->e_uid)); + break; + case ACL_GROUP: + ext_entry->e_id = + cpu_to_le32(from_kgid(user_ns, acl_e->e_gid)); + break; + default: + ext_entry->e_id = cpu_to_le32(ACL_UNDEFINED_ID); + break; + } + } + return real_size; +} +EXPORT_SYMBOL (posix_acl_to_xattr); -- cgit