![Linus Torvalds](/assets/img/avatar_default.png)
but instead the widening contributor base. It is good to see that interest is increasing in GFS2, and I'd like to thank all the contributors to this patch set. In addition to the usual set of bug fixes and clean ups, there are patches to improve inode creation performance when xattrs are required and some improvements to the transaction code which is intended to help improve scalability after further changes in due course. Journal extent mapping is also updated to make it more efficient and again, this is a foundation for future work in this area. The maximum number of ACLs has been increased to 300 (for a 4k block size) which means that even with a few additional xattrs from selinux, everything should fit within a single fs block. There is also a patch to bring GFS2's own copy of the writepages code up to the same level as the core VFS. Eventually we may be able to merge some of this code, since it is fairly similar. The other major change this time, is bringing consistency to the printing of messages via fs_<level>, pr_<level> macros. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.15 (GNU/Linux) iQIcBAABAgAGBQJTOn+JAAoJEMrg3m4a/8jSSoYQALctSOmyGW978JMAKiwuUeSr 367ho/I/WfZWybWH7iZ/hdEMNCUCnP3C1ZJhYKJ6J60h35p1hIK7DYp9tOy0RsTS JD3VamE/jboljXyZaaMCtly7HPQMV82rRmI3+bSoXpT4mPz+PB+kRCe2QkvyVAsh 5tojtLz6L/In/eo4UlqZjn1BITcYRL5AgMi+8h8h6Foi4MgnFISZbezC6U5eO46P DT/xwd0fw+o5ZTm/dTQmhCCH30y4cpKZnNhi+xhHrEm95gBZWcONHD0qyNZe3fBc WuGUU9hURHHkqT671T7sBGzfNrsKk1OgNzFNy1YrF5C+t6hpG9iAKRIHtuVqSqPx OblhKP0lebDY1L41NqZR4Up+pUjCMxOs3f+FAl2rlHRBIQdroOu82CZHdTBfM/HJ 1ZvkMrIkxMKb7RtSnTdXsPxcPPZNakHhDaNxHMmMlFlflbXGQqWZaMMhK181d7dn Y0WU2ayPmjjUdO5OnekMV5J/hNYNLobnV9OO75j4pyqlnHLIIycc/wgNULcU+OJ6 GooOQJNnnAo+2JUvS+Ejn88q2if05HOg4fCXRfu4bdA2zDehei1jr5xz5IWj0OAM AlmTgUYzK7osvA1XtNd6naCmes+fnm3+Jfh0+YtpeZKgCvaYYCoZCHJccb+a0AIq 7dTkyCQtgsKE+yjPKose =IWmZ -----END PGP SIGNATURE----- Merge tag 'gfs2-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-3.0-nmw Pull GFS2 updates from Steven Whitehouse: "One of the main highlights this time, is not the patches themselves but instead the widening contributor base. It is good to see that interest is increasing in GFS2, and I'd like to thank all the contributors to this patch set. In addition to the usual set of bug fixes and clean ups, there are patches to improve inode creation performance when xattrs are required and some improvements to the transaction code which is intended to help improve scalability after further changes in due course. Journal extent mapping is also updated to make it more efficient and again, this is a foundation for future work in this area. The maximum number of ACLs has been increased to 300 (for a 4k block size) which means that even with a few additional xattrs from selinux, everything should fit within a single fs block. There is also a patch to bring GFS2's own copy of the writepages code up to the same level as the core VFS. Eventually we may be able to merge some of this code, since it is fairly similar. The other major change this time, is bringing consistency to the printing of messages via fs_<level>, pr_<level> macros" * tag 'gfs2-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-3.0-nmw: (29 commits) GFS2: Fix address space from page function GFS2: Fix uninitialized VFS inode in gfs2_create_inode GFS2: Fix return value in slot_get() GFS2: inline function gfs2_set_mode GFS2: Remove extraneous function gfs2_security_init GFS2: Increase the max number of ACLs GFS2: Re-add a call to log_flush_wait when flushing the journal GFS2: Ensure workqueue is scheduled after noexp request GFS2: check NULL return value in gfs2_ok_to_move GFS2: Convert gfs2_lm_withdraw to use fs_err GFS2: Use fs_<level> more often GFS2: Use pr_<level> more consistently GFS2: Move recovery variables to journal structure in memory GFS2: global conversion to pr_foo() GFS2: return -E2BIG if hit the maximum limits of ACLs GFS2: Clean up journal extent mapping GFS2: replace kmalloc - __vmalloc / memset 0 GFS2: Remove extra "if" in gfs2_log_flush() fs: NULL dereference in posix_acl_to_xattr() GFS2: Move log buffer accounting to transaction ...
896 lines
20 KiB
C
896 lines
20 KiB
C
/*
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* Copyright (C) 2002,2003 by Andreas Gruenbacher <a.gruenbacher@computer.org>
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*
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* Fixes from William Schumacher incorporated on 15 March 2001.
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* (Reported by Charles Bertsch, <CBertsch@microtest.com>).
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*/
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/*
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* This file contains generic functions for manipulating
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* POSIX 1003.1e draft standard 17 ACLs.
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*/
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#include <linux/kernel.h>
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#include <linux/slab.h>
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#include <linux/atomic.h>
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#include <linux/fs.h>
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#include <linux/sched.h>
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#include <linux/posix_acl.h>
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#include <linux/posix_acl_xattr.h>
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#include <linux/xattr.h>
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#include <linux/export.h>
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#include <linux/user_namespace.h>
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struct posix_acl **acl_by_type(struct inode *inode, int type)
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{
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switch (type) {
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case ACL_TYPE_ACCESS:
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return &inode->i_acl;
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case ACL_TYPE_DEFAULT:
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return &inode->i_default_acl;
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default:
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BUG();
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}
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}
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EXPORT_SYMBOL(acl_by_type);
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struct posix_acl *get_cached_acl(struct inode *inode, int type)
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{
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struct posix_acl **p = acl_by_type(inode, type);
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struct posix_acl *acl = ACCESS_ONCE(*p);
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if (acl) {
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spin_lock(&inode->i_lock);
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acl = *p;
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if (acl != ACL_NOT_CACHED)
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acl = posix_acl_dup(acl);
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spin_unlock(&inode->i_lock);
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}
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return acl;
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}
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EXPORT_SYMBOL(get_cached_acl);
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struct posix_acl *get_cached_acl_rcu(struct inode *inode, int type)
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{
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return rcu_dereference(*acl_by_type(inode, type));
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}
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EXPORT_SYMBOL(get_cached_acl_rcu);
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void set_cached_acl(struct inode *inode, int type, struct posix_acl *acl)
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{
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struct posix_acl **p = acl_by_type(inode, type);
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struct posix_acl *old;
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spin_lock(&inode->i_lock);
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old = *p;
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rcu_assign_pointer(*p, posix_acl_dup(acl));
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spin_unlock(&inode->i_lock);
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if (old != ACL_NOT_CACHED)
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posix_acl_release(old);
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}
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EXPORT_SYMBOL(set_cached_acl);
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void forget_cached_acl(struct inode *inode, int type)
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{
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struct posix_acl **p = acl_by_type(inode, type);
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struct posix_acl *old;
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spin_lock(&inode->i_lock);
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old = *p;
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*p = ACL_NOT_CACHED;
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spin_unlock(&inode->i_lock);
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if (old != ACL_NOT_CACHED)
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posix_acl_release(old);
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}
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EXPORT_SYMBOL(forget_cached_acl);
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void forget_all_cached_acls(struct inode *inode)
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{
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struct posix_acl *old_access, *old_default;
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spin_lock(&inode->i_lock);
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old_access = inode->i_acl;
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old_default = inode->i_default_acl;
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inode->i_acl = inode->i_default_acl = ACL_NOT_CACHED;
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spin_unlock(&inode->i_lock);
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if (old_access != ACL_NOT_CACHED)
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posix_acl_release(old_access);
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if (old_default != ACL_NOT_CACHED)
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posix_acl_release(old_default);
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}
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EXPORT_SYMBOL(forget_all_cached_acls);
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struct posix_acl *get_acl(struct inode *inode, int type)
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{
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struct posix_acl *acl;
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acl = get_cached_acl(inode, type);
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if (acl != ACL_NOT_CACHED)
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return acl;
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if (!IS_POSIXACL(inode))
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return NULL;
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/*
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* A filesystem can force a ACL callback by just never filling the
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* ACL cache. But normally you'd fill the cache either at inode
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* instantiation time, or on the first ->get_acl call.
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*
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* If the filesystem doesn't have a get_acl() function at all, we'll
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* just create the negative cache entry.
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*/
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if (!inode->i_op->get_acl) {
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set_cached_acl(inode, type, NULL);
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return NULL;
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}
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return inode->i_op->get_acl(inode, type);
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}
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EXPORT_SYMBOL(get_acl);
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/*
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* Init a fresh posix_acl
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*/
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void
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posix_acl_init(struct posix_acl *acl, int count)
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{
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atomic_set(&acl->a_refcount, 1);
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acl->a_count = count;
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}
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EXPORT_SYMBOL(posix_acl_init);
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/*
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* Allocate a new ACL with the specified number of entries.
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*/
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struct posix_acl *
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posix_acl_alloc(int count, gfp_t flags)
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{
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const size_t size = sizeof(struct posix_acl) +
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count * sizeof(struct posix_acl_entry);
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struct posix_acl *acl = kmalloc(size, flags);
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if (acl)
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posix_acl_init(acl, count);
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return acl;
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}
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EXPORT_SYMBOL(posix_acl_alloc);
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/*
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* Clone an ACL.
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*/
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static struct posix_acl *
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posix_acl_clone(const struct posix_acl *acl, gfp_t flags)
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{
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struct posix_acl *clone = NULL;
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if (acl) {
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int size = sizeof(struct posix_acl) + acl->a_count *
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sizeof(struct posix_acl_entry);
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clone = kmemdup(acl, size, flags);
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if (clone)
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atomic_set(&clone->a_refcount, 1);
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}
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return clone;
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}
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/*
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* Check if an acl is valid. Returns 0 if it is, or -E... otherwise.
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*/
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int
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posix_acl_valid(const struct posix_acl *acl)
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{
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const struct posix_acl_entry *pa, *pe;
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int state = ACL_USER_OBJ;
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int needs_mask = 0;
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FOREACH_ACL_ENTRY(pa, acl, pe) {
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if (pa->e_perm & ~(ACL_READ|ACL_WRITE|ACL_EXECUTE))
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return -EINVAL;
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switch (pa->e_tag) {
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case ACL_USER_OBJ:
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if (state == ACL_USER_OBJ) {
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state = ACL_USER;
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break;
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}
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return -EINVAL;
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case ACL_USER:
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if (state != ACL_USER)
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return -EINVAL;
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if (!uid_valid(pa->e_uid))
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return -EINVAL;
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needs_mask = 1;
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break;
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case ACL_GROUP_OBJ:
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if (state == ACL_USER) {
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state = ACL_GROUP;
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break;
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}
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return -EINVAL;
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case ACL_GROUP:
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if (state != ACL_GROUP)
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return -EINVAL;
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if (!gid_valid(pa->e_gid))
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return -EINVAL;
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needs_mask = 1;
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break;
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case ACL_MASK:
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if (state != ACL_GROUP)
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return -EINVAL;
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state = ACL_OTHER;
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break;
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case ACL_OTHER:
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if (state == ACL_OTHER ||
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(state == ACL_GROUP && !needs_mask)) {
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state = 0;
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break;
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}
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return -EINVAL;
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default:
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return -EINVAL;
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}
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}
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if (state == 0)
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return 0;
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return -EINVAL;
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}
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EXPORT_SYMBOL(posix_acl_valid);
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/*
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* Returns 0 if the acl can be exactly represented in the traditional
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* file mode permission bits, or else 1. Returns -E... on error.
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*/
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int
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posix_acl_equiv_mode(const struct posix_acl *acl, umode_t *mode_p)
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{
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const struct posix_acl_entry *pa, *pe;
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umode_t mode = 0;
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int not_equiv = 0;
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FOREACH_ACL_ENTRY(pa, acl, pe) {
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switch (pa->e_tag) {
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case ACL_USER_OBJ:
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mode |= (pa->e_perm & S_IRWXO) << 6;
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break;
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case ACL_GROUP_OBJ:
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mode |= (pa->e_perm & S_IRWXO) << 3;
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break;
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case ACL_OTHER:
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mode |= pa->e_perm & S_IRWXO;
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break;
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case ACL_MASK:
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mode = (mode & ~S_IRWXG) |
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((pa->e_perm & S_IRWXO) << 3);
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not_equiv = 1;
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break;
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case ACL_USER:
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case ACL_GROUP:
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not_equiv = 1;
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break;
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default:
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return -EINVAL;
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}
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}
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if (mode_p)
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*mode_p = (*mode_p & ~S_IRWXUGO) | mode;
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return not_equiv;
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}
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EXPORT_SYMBOL(posix_acl_equiv_mode);
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/*
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* Create an ACL representing the file mode permission bits of an inode.
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*/
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struct posix_acl *
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posix_acl_from_mode(umode_t mode, gfp_t flags)
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{
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struct posix_acl *acl = posix_acl_alloc(3, flags);
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if (!acl)
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return ERR_PTR(-ENOMEM);
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acl->a_entries[0].e_tag = ACL_USER_OBJ;
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acl->a_entries[0].e_perm = (mode & S_IRWXU) >> 6;
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acl->a_entries[1].e_tag = ACL_GROUP_OBJ;
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acl->a_entries[1].e_perm = (mode & S_IRWXG) >> 3;
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acl->a_entries[2].e_tag = ACL_OTHER;
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acl->a_entries[2].e_perm = (mode & S_IRWXO);
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return acl;
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}
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EXPORT_SYMBOL(posix_acl_from_mode);
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/*
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* Return 0 if current is granted want access to the inode
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* by the acl. Returns -E... otherwise.
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*/
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int
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posix_acl_permission(struct inode *inode, const struct posix_acl *acl, int want)
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{
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const struct posix_acl_entry *pa, *pe, *mask_obj;
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int found = 0;
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want &= MAY_READ | MAY_WRITE | MAY_EXEC | MAY_NOT_BLOCK;
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FOREACH_ACL_ENTRY(pa, acl, pe) {
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switch(pa->e_tag) {
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case ACL_USER_OBJ:
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/* (May have been checked already) */
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if (uid_eq(inode->i_uid, current_fsuid()))
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goto check_perm;
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break;
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case ACL_USER:
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if (uid_eq(pa->e_uid, current_fsuid()))
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goto mask;
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break;
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case ACL_GROUP_OBJ:
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if (in_group_p(inode->i_gid)) {
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found = 1;
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if ((pa->e_perm & want) == want)
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goto mask;
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}
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break;
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case ACL_GROUP:
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if (in_group_p(pa->e_gid)) {
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found = 1;
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if ((pa->e_perm & want) == want)
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goto mask;
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}
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break;
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case ACL_MASK:
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break;
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case ACL_OTHER:
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if (found)
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return -EACCES;
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else
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goto check_perm;
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default:
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return -EIO;
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}
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}
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return -EIO;
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mask:
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for (mask_obj = pa+1; mask_obj != pe; mask_obj++) {
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if (mask_obj->e_tag == ACL_MASK) {
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if ((pa->e_perm & mask_obj->e_perm & want) == want)
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return 0;
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return -EACCES;
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}
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}
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check_perm:
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if ((pa->e_perm & want) == want)
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return 0;
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return -EACCES;
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}
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/*
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* Modify acl when creating a new inode. The caller must ensure the acl is
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* only referenced once.
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*
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* mode_p initially must contain the mode parameter to the open() / creat()
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* system calls. All permissions that are not granted by the acl are removed.
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* The permissions in the acl are changed to reflect the mode_p parameter.
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*/
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static int posix_acl_create_masq(struct posix_acl *acl, umode_t *mode_p)
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{
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struct posix_acl_entry *pa, *pe;
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struct posix_acl_entry *group_obj = NULL, *mask_obj = NULL;
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umode_t mode = *mode_p;
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int not_equiv = 0;
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/* assert(atomic_read(acl->a_refcount) == 1); */
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FOREACH_ACL_ENTRY(pa, acl, pe) {
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switch(pa->e_tag) {
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case ACL_USER_OBJ:
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pa->e_perm &= (mode >> 6) | ~S_IRWXO;
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mode &= (pa->e_perm << 6) | ~S_IRWXU;
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break;
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case ACL_USER:
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case ACL_GROUP:
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not_equiv = 1;
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break;
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case ACL_GROUP_OBJ:
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group_obj = pa;
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break;
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case ACL_OTHER:
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pa->e_perm &= mode | ~S_IRWXO;
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mode &= pa->e_perm | ~S_IRWXO;
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break;
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case ACL_MASK:
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mask_obj = pa;
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not_equiv = 1;
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break;
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default:
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return -EIO;
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}
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}
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if (mask_obj) {
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mask_obj->e_perm &= (mode >> 3) | ~S_IRWXO;
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mode &= (mask_obj->e_perm << 3) | ~S_IRWXG;
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} else {
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if (!group_obj)
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return -EIO;
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group_obj->e_perm &= (mode >> 3) | ~S_IRWXO;
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mode &= (group_obj->e_perm << 3) | ~S_IRWXG;
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}
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*mode_p = (*mode_p & ~S_IRWXUGO) | mode;
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return not_equiv;
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}
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/*
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* Modify the ACL for the chmod syscall.
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*/
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static int __posix_acl_chmod_masq(struct posix_acl *acl, umode_t mode)
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{
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struct posix_acl_entry *group_obj = NULL, *mask_obj = NULL;
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struct posix_acl_entry *pa, *pe;
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/* assert(atomic_read(acl->a_refcount) == 1); */
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FOREACH_ACL_ENTRY(pa, acl, pe) {
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switch(pa->e_tag) {
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case ACL_USER_OBJ:
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pa->e_perm = (mode & S_IRWXU) >> 6;
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break;
|
|
|
|
case ACL_USER:
|
|
case ACL_GROUP:
|
|
break;
|
|
|
|
case ACL_GROUP_OBJ:
|
|
group_obj = pa;
|
|
break;
|
|
|
|
case ACL_MASK:
|
|
mask_obj = pa;
|
|
break;
|
|
|
|
case ACL_OTHER:
|
|
pa->e_perm = (mode & S_IRWXO);
|
|
break;
|
|
|
|
default:
|
|
return -EIO;
|
|
}
|
|
}
|
|
|
|
if (mask_obj) {
|
|
mask_obj->e_perm = (mode & S_IRWXG) >> 3;
|
|
} else {
|
|
if (!group_obj)
|
|
return -EIO;
|
|
group_obj->e_perm = (mode & S_IRWXG) >> 3;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
int
|
|
__posix_acl_create(struct posix_acl **acl, gfp_t gfp, umode_t *mode_p)
|
|
{
|
|
struct posix_acl *clone = posix_acl_clone(*acl, gfp);
|
|
int err = -ENOMEM;
|
|
if (clone) {
|
|
err = posix_acl_create_masq(clone, mode_p);
|
|
if (err < 0) {
|
|
posix_acl_release(clone);
|
|
clone = NULL;
|
|
}
|
|
}
|
|
posix_acl_release(*acl);
|
|
*acl = clone;
|
|
return err;
|
|
}
|
|
EXPORT_SYMBOL(__posix_acl_create);
|
|
|
|
int
|
|
__posix_acl_chmod(struct posix_acl **acl, gfp_t gfp, umode_t mode)
|
|
{
|
|
struct posix_acl *clone = posix_acl_clone(*acl, gfp);
|
|
int err = -ENOMEM;
|
|
if (clone) {
|
|
err = __posix_acl_chmod_masq(clone, mode);
|
|
if (err) {
|
|
posix_acl_release(clone);
|
|
clone = NULL;
|
|
}
|
|
}
|
|
posix_acl_release(*acl);
|
|
*acl = clone;
|
|
return err;
|
|
}
|
|
EXPORT_SYMBOL(__posix_acl_chmod);
|
|
|
|
int
|
|
posix_acl_chmod(struct inode *inode, umode_t mode)
|
|
{
|
|
struct posix_acl *acl;
|
|
int ret = 0;
|
|
|
|
if (!IS_POSIXACL(inode))
|
|
return 0;
|
|
if (!inode->i_op->set_acl)
|
|
return -EOPNOTSUPP;
|
|
|
|
acl = get_acl(inode, ACL_TYPE_ACCESS);
|
|
if (IS_ERR_OR_NULL(acl)) {
|
|
if (acl == ERR_PTR(-EOPNOTSUPP))
|
|
return 0;
|
|
return PTR_ERR(acl);
|
|
}
|
|
|
|
ret = __posix_acl_chmod(&acl, GFP_KERNEL, mode);
|
|
if (ret)
|
|
return ret;
|
|
ret = inode->i_op->set_acl(inode, acl, ACL_TYPE_ACCESS);
|
|
posix_acl_release(acl);
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL(posix_acl_chmod);
|
|
|
|
int
|
|
posix_acl_create(struct inode *dir, umode_t *mode,
|
|
struct posix_acl **default_acl, struct posix_acl **acl)
|
|
{
|
|
struct posix_acl *p;
|
|
int ret;
|
|
|
|
if (S_ISLNK(*mode) || !IS_POSIXACL(dir))
|
|
goto no_acl;
|
|
|
|
p = get_acl(dir, ACL_TYPE_DEFAULT);
|
|
if (IS_ERR(p)) {
|
|
if (p == ERR_PTR(-EOPNOTSUPP))
|
|
goto apply_umask;
|
|
return PTR_ERR(p);
|
|
}
|
|
|
|
if (!p)
|
|
goto apply_umask;
|
|
|
|
*acl = posix_acl_clone(p, GFP_NOFS);
|
|
if (!*acl)
|
|
return -ENOMEM;
|
|
|
|
ret = posix_acl_create_masq(*acl, mode);
|
|
if (ret < 0) {
|
|
posix_acl_release(*acl);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
if (ret == 0) {
|
|
posix_acl_release(*acl);
|
|
*acl = NULL;
|
|
}
|
|
|
|
if (!S_ISDIR(*mode)) {
|
|
posix_acl_release(p);
|
|
*default_acl = NULL;
|
|
} else {
|
|
*default_acl = p;
|
|
}
|
|
return 0;
|
|
|
|
apply_umask:
|
|
*mode &= ~current_umask();
|
|
no_acl:
|
|
*default_acl = NULL;
|
|
*acl = NULL;
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(posix_acl_create);
|
|
|
|
/*
|
|
* 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;
|
|
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_entry = ext_acl->a_entries;
|
|
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);
|
|
|
|
static int
|
|
posix_acl_xattr_get(struct dentry *dentry, const char *name,
|
|
void *value, size_t size, int type)
|
|
{
|
|
struct posix_acl *acl;
|
|
int error;
|
|
|
|
if (!IS_POSIXACL(dentry->d_inode))
|
|
return -EOPNOTSUPP;
|
|
if (S_ISLNK(dentry->d_inode->i_mode))
|
|
return -EOPNOTSUPP;
|
|
|
|
acl = get_acl(dentry->d_inode, type);
|
|
if (IS_ERR(acl))
|
|
return PTR_ERR(acl);
|
|
if (acl == NULL)
|
|
return -ENODATA;
|
|
|
|
error = posix_acl_to_xattr(&init_user_ns, acl, value, size);
|
|
posix_acl_release(acl);
|
|
|
|
return error;
|
|
}
|
|
|
|
static int
|
|
posix_acl_xattr_set(struct dentry *dentry, const char *name,
|
|
const void *value, size_t size, int flags, int type)
|
|
{
|
|
struct inode *inode = dentry->d_inode;
|
|
struct posix_acl *acl = NULL;
|
|
int ret;
|
|
|
|
if (!IS_POSIXACL(inode))
|
|
return -EOPNOTSUPP;
|
|
if (!inode->i_op->set_acl)
|
|
return -EOPNOTSUPP;
|
|
|
|
if (type == ACL_TYPE_DEFAULT && !S_ISDIR(inode->i_mode))
|
|
return value ? -EACCES : 0;
|
|
if (!inode_owner_or_capable(inode))
|
|
return -EPERM;
|
|
|
|
if (value) {
|
|
acl = posix_acl_from_xattr(&init_user_ns, value, size);
|
|
if (IS_ERR(acl))
|
|
return PTR_ERR(acl);
|
|
|
|
if (acl) {
|
|
ret = posix_acl_valid(acl);
|
|
if (ret)
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
ret = inode->i_op->set_acl(inode, acl, type);
|
|
out:
|
|
posix_acl_release(acl);
|
|
return ret;
|
|
}
|
|
|
|
static size_t
|
|
posix_acl_xattr_list(struct dentry *dentry, char *list, size_t list_size,
|
|
const char *name, size_t name_len, int type)
|
|
{
|
|
const char *xname;
|
|
size_t size;
|
|
|
|
if (!IS_POSIXACL(dentry->d_inode))
|
|
return -EOPNOTSUPP;
|
|
if (S_ISLNK(dentry->d_inode->i_mode))
|
|
return -EOPNOTSUPP;
|
|
|
|
if (type == ACL_TYPE_ACCESS)
|
|
xname = POSIX_ACL_XATTR_ACCESS;
|
|
else
|
|
xname = POSIX_ACL_XATTR_DEFAULT;
|
|
|
|
size = strlen(xname) + 1;
|
|
if (list && size <= list_size)
|
|
memcpy(list, xname, size);
|
|
return size;
|
|
}
|
|
|
|
const struct xattr_handler posix_acl_access_xattr_handler = {
|
|
.prefix = POSIX_ACL_XATTR_ACCESS,
|
|
.flags = ACL_TYPE_ACCESS,
|
|
.list = posix_acl_xattr_list,
|
|
.get = posix_acl_xattr_get,
|
|
.set = posix_acl_xattr_set,
|
|
};
|
|
EXPORT_SYMBOL_GPL(posix_acl_access_xattr_handler);
|
|
|
|
const struct xattr_handler posix_acl_default_xattr_handler = {
|
|
.prefix = POSIX_ACL_XATTR_DEFAULT,
|
|
.flags = ACL_TYPE_DEFAULT,
|
|
.list = posix_acl_xattr_list,
|
|
.get = posix_acl_xattr_get,
|
|
.set = posix_acl_xattr_set,
|
|
};
|
|
EXPORT_SYMBOL_GPL(posix_acl_default_xattr_handler);
|
|
|
|
int simple_set_acl(struct inode *inode, struct posix_acl *acl, int type)
|
|
{
|
|
int error;
|
|
|
|
if (type == ACL_TYPE_ACCESS) {
|
|
error = posix_acl_equiv_mode(acl, &inode->i_mode);
|
|
if (error < 0)
|
|
return 0;
|
|
if (error == 0)
|
|
acl = NULL;
|
|
}
|
|
|
|
inode->i_ctime = CURRENT_TIME;
|
|
set_cached_acl(inode, type, acl);
|
|
return 0;
|
|
}
|
|
|
|
int simple_acl_create(struct inode *dir, struct inode *inode)
|
|
{
|
|
struct posix_acl *default_acl, *acl;
|
|
int error;
|
|
|
|
error = posix_acl_create(dir, &inode->i_mode, &default_acl, &acl);
|
|
if (error)
|
|
return error;
|
|
|
|
set_cached_acl(inode, ACL_TYPE_DEFAULT, default_acl);
|
|
set_cached_acl(inode, ACL_TYPE_ACCESS, acl);
|
|
|
|
if (default_acl)
|
|
posix_acl_release(default_acl);
|
|
if (acl)
|
|
posix_acl_release(acl);
|
|
return 0;
|
|
}
|