Merge git://git.kernel.org/pub/scm/linux/kernel/git/hch/xfs-icache-races

* git://git.kernel.org/pub/scm/linux/kernel/git/hch/xfs-icache-races:
  xfs: fix freeing of inodes not yet added to the inode cache
  vfs: add __destroy_inode
  vfs: fix inode_init_always calling convention

4 files changed, 99 insertions, 103 deletions

diff --git a/fs/inode.c b/fs/inode.c
index 901bad1e5f1..ae7b67e4866 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -120,12 +120,11 @@ static void wake_up_inode(struct inode *inode)
  * These are initializations that need to be done on every inode
  * allocation as the fields are not initialised by slab allocation.
  */
-struct inode *inode_init_always(struct super_block *sb, struct inode *inode)
+int inode_init_always(struct super_block *sb, struct inode *inode)
 {
         static const struct address_space_operations empty_aops;
         static struct inode_operations empty_iops;
         static const struct file_operations empty_fops;
-
         struct address_space *const mapping = &inode->i_data;
 
         inode->i_sb = sb;
@@ -152,7 +151,7 @@ struct inode *inode_init_always(struct super_block *sb, struct inode *inode)
         inode->dirtied_when = 0;
 
         if (security_inode_alloc(inode))
-                goto out_free_inode;
+                goto out;
 
         /* allocate and initialize an i_integrity */
         if (ima_inode_alloc(inode))
@@ -198,16 +197,12 @@ struct inode *inode_init_always(struct super_block *sb, struct inode *inode)
         inode->i_fsnotify_mask = 0;
 #endif
 
-        return inode;
+        return 0;
 
 out_free_security:
         security_inode_free(inode);
-out_free_inode:
-        if (inode->i_sb->s_op->destroy_inode)
-                inode->i_sb->s_op->destroy_inode(inode);
-        else
-                kmem_cache_free(inode_cachep, (inode));
-        return NULL;
+out:
+        return -ENOMEM;
 }
 EXPORT_SYMBOL(inode_init_always);
 
@@ -220,12 +215,21 @@ static struct inode *alloc_inode(struct super_block *sb)
         else
                 inode = kmem_cache_alloc(inode_cachep, GFP_KERNEL);
 
-        if (inode)
-                return inode_init_always(sb, inode);
-        return NULL;
+        if (!inode)
+                return NULL;
+
+        if (unlikely(inode_init_always(sb, inode))) {
+                if (inode->i_sb->s_op->destroy_inode)
+                        inode->i_sb->s_op->destroy_inode(inode);
+                else
+                        kmem_cache_free(inode_cachep, inode);
+                return NULL;
+        }
+
+        return inode;
 }
 
-void destroy_inode(struct inode *inode)
+void __destroy_inode(struct inode *inode)
 {
         BUG_ON(inode_has_buffers(inode));
         ima_inode_free(inode);
@@ -237,13 +241,17 @@ void destroy_inode(struct inode *inode)
         if (inode->i_default_acl && inode->i_default_acl != ACL_NOT_CACHED)
                 posix_acl_release(inode->i_default_acl);
 #endif
+}
+EXPORT_SYMBOL(__destroy_inode);
+
+void destroy_inode(struct inode *inode)
+{
+        __destroy_inode(inode);
         if (inode->i_sb->s_op->destroy_inode)
                 inode->i_sb->s_op->destroy_inode(inode);
         else
                 kmem_cache_free(inode_cachep, (inode));
 }
-EXPORT_SYMBOL(destroy_inode);
-
 
 /*
  * These are initializations that only need to be done
diff --git a/fs/xfs/xfs_iget.c b/fs/xfs/xfs_iget.c
index 5fcec6f020a..34ec86923f7 100644
--- a/fs/xfs/xfs_iget.c
+++ b/fs/xfs/xfs_iget.c
@@ -64,6 +64,10 @@ xfs_inode_alloc(
         ip = kmem_zone_alloc(xfs_inode_zone, KM_SLEEP);
         if (!ip)
                 return NULL;
+        if (inode_init_always(mp->m_super, VFS_I(ip))) {
+                kmem_zone_free(xfs_inode_zone, ip);
+                return NULL;
+        }
 
         ASSERT(atomic_read(&ip->i_iocount) == 0);
         ASSERT(atomic_read(&ip->i_pincount) == 0);
@@ -105,17 +109,6 @@ xfs_inode_alloc(
 #ifdef XFS_DIR2_TRACE
         ip->i_dir_trace = ktrace_alloc(XFS_DIR2_KTRACE_SIZE, KM_NOFS);
 #endif
-        /*
-        * Now initialise the VFS inode. We do this after the xfs_inode
-        * initialisation as internal failures will result in ->destroy_inode
-        * being called and that will pass down through the reclaim path and
-        * free the XFS inode. This path requires the XFS inode to already be
-        * initialised. Hence if this call fails, the xfs_inode has already
-        * been freed and we should not reference it at all in the error
-        * handling.
-        */
-        if (!inode_init_always(mp->m_super, VFS_I(ip)))
-                return NULL;
 
         /* prevent anyone from using this yet */
         VFS_I(ip)->i_state = I_NEW|I_LOCK;
@@ -123,6 +116,71 @@ xfs_inode_alloc(
         return ip;
 }
 
+STATIC void
+xfs_inode_free(
+        struct xfs_inode        *ip)
+{
+        switch (ip->i_d.di_mode & S_IFMT) {
+        case S_IFREG:
+        case S_IFDIR:
+        case S_IFLNK:
+                xfs_idestroy_fork(ip, XFS_DATA_FORK);
+                break;
+        }
+
+        if (ip->i_afp)
+                xfs_idestroy_fork(ip, XFS_ATTR_FORK);
+
+#ifdef XFS_INODE_TRACE
+        ktrace_free(ip->i_trace);
+#endif
+#ifdef XFS_BMAP_TRACE
+        ktrace_free(ip->i_xtrace);
+#endif
+#ifdef XFS_BTREE_TRACE
+        ktrace_free(ip->i_btrace);
+#endif
+#ifdef XFS_RW_TRACE
+        ktrace_free(ip->i_rwtrace);
+#endif
+#ifdef XFS_ILOCK_TRACE
+        ktrace_free(ip->i_lock_trace);
+#endif
+#ifdef XFS_DIR2_TRACE
+        ktrace_free(ip->i_dir_trace);
+#endif
+
+        if (ip->i_itemp) {
+                /*
+                 * Only if we are shutting down the fs will we see an
+                 * inode still in the AIL. If it is there, we should remove
+                 * it to prevent a use-after-free from occurring.
+                 */
+                xfs_log_item_t  *lip = &ip->i_itemp->ili_item;
+                struct xfs_ail  *ailp = lip->li_ailp;
+
+                ASSERT(((lip->li_flags & XFS_LI_IN_AIL) == 0) ||
+                                       XFS_FORCED_SHUTDOWN(ip->i_mount));
+                if (lip->li_flags & XFS_LI_IN_AIL) {
+                        spin_lock(&ailp->xa_lock);
+                        if (lip->li_flags & XFS_LI_IN_AIL)
+                                xfs_trans_ail_delete(ailp, lip);
+                        else
+                                spin_unlock(&ailp->xa_lock);
+                }
+                xfs_inode_item_destroy(ip);
+                ip->i_itemp = NULL;
+        }
+
+        /* asserts to verify all state is correct here */
+        ASSERT(atomic_read(&ip->i_iocount) == 0);
+        ASSERT(atomic_read(&ip->i_pincount) == 0);
+        ASSERT(!spin_is_locked(&ip->i_flags_lock));
+        ASSERT(completion_done(&ip->i_flush));
+
+        kmem_zone_free(xfs_inode_zone, ip);
+}
+
 /*
  * Check the validity of the inode we just found it the cache
  */
@@ -167,7 +225,7 @@ xfs_iget_cache_hit(
                  * errors cleanly, then tag it so it can be set up correctly
                  * later.
                  */
-                if (!inode_init_always(mp->m_super, VFS_I(ip))) {
+                if (inode_init_always(mp->m_super, VFS_I(ip))) {
                         error = ENOMEM;
                         goto out_error;
                 }
@@ -299,7 +357,8 @@ out_preload_end:
         if (lock_flags)
                 xfs_iunlock(ip, lock_flags);
 out_destroy:
-        xfs_destroy_inode(ip);
+        __destroy_inode(VFS_I(ip));
+        xfs_inode_free(ip);
         return error;
 }
 
@@ -504,62 +563,7 @@ xfs_ireclaim(
         xfs_qm_dqdetach(ip);
         xfs_iunlock(ip, XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL);
 
-        switch (ip->i_d.di_mode & S_IFMT) {
-        case S_IFREG:
-        case S_IFDIR:
-        case S_IFLNK:
-                xfs_idestroy_fork(ip, XFS_DATA_FORK);
-                break;
-        }
-
-        if (ip->i_afp)
-                xfs_idestroy_fork(ip, XFS_ATTR_FORK);
-
-#ifdef XFS_INODE_TRACE
-        ktrace_free(ip->i_trace);
-#endif
-#ifdef XFS_BMAP_TRACE
-        ktrace_free(ip->i_xtrace);
-#endif
-#ifdef XFS_BTREE_TRACE
-        ktrace_free(ip->i_btrace);
-#endif
-#ifdef XFS_RW_TRACE
-        ktrace_free(ip->i_rwtrace);
-#endif
-#ifdef XFS_ILOCK_TRACE
-        ktrace_free(ip->i_lock_trace);
-#endif
-#ifdef XFS_DIR2_TRACE
-        ktrace_free(ip->i_dir_trace);
-#endif
-        if (ip->i_itemp) {
-                /*
-                 * Only if we are shutting down the fs will we see an
-                 * inode still in the AIL. If it is there, we should remove
-                 * it to prevent a use-after-free from occurring.
-                 */
-                xfs_log_item_t  *lip = &ip->i_itemp->ili_item;
-                struct xfs_ail  *ailp = lip->li_ailp;
-
-                ASSERT(((lip->li_flags & XFS_LI_IN_AIL) == 0) ||
-                                       XFS_FORCED_SHUTDOWN(ip->i_mount));
-                if (lip->li_flags & XFS_LI_IN_AIL) {
-                        spin_lock(&ailp->xa_lock);
-                        if (lip->li_flags & XFS_LI_IN_AIL)
-                                xfs_trans_ail_delete(ailp, lip);
-                        else
-                                spin_unlock(&ailp->xa_lock);
-                }
-                xfs_inode_item_destroy(ip);
-                ip->i_itemp = NULL;
-        }
-        /* asserts to verify all state is correct here */
-        ASSERT(atomic_read(&ip->i_iocount) == 0);
-        ASSERT(atomic_read(&ip->i_pincount) == 0);
-        ASSERT(!spin_is_locked(&ip->i_flags_lock));
-        ASSERT(completion_done(&ip->i_flush));
-        kmem_zone_free(xfs_inode_zone, ip);
+        xfs_inode_free(ip);
 }
 
 /*
diff --git a/fs/xfs/xfs_inode.h b/fs/xfs/xfs_inode.h
index 1804f866a71..65f24a3cc99 100644
--- a/fs/xfs/xfs_inode.h
+++ b/fs/xfs/xfs_inode.h
@@ -310,23 +310,6 @@ static inline struct inode *VFS_I(struct xfs_inode *ip)
 }
 
 /*
- * Get rid of a partially initialized inode.
- *
- * We have to go through destroy_inode to make sure allocations
- * from init_inode_always like the security data are undone.
- *
- * We mark the inode bad so that it takes the short cut in
- * the reclaim path instead of going through the flush path
- * which doesn't make sense for an inode that has never seen the
- * light of day.
- */
-static inline void xfs_destroy_inode(struct xfs_inode *ip)
-{
-        make_bad_inode(VFS_I(ip));
-        return destroy_inode(VFS_I(ip));
-}
-
-/*
  * i_flags helper functions
  */
 static inline void
diff --git a/include/linux/fs.h b/include/linux/fs.h
index a36ffa5a77a..67888a9e065 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2137,7 +2137,7 @@ extern loff_t default_llseek(struct file *file, loff_t offset, int origin);
 
 extern loff_t vfs_llseek(struct file *file, loff_t offset, int origin);
 
-extern struct inode * inode_init_always(struct super_block *, struct inode *);
+extern int inode_init_always(struct super_block *, struct inode *);
 extern void inode_init_once(struct inode *);
 extern void inode_add_to_lists(struct super_block *, struct inode *);
 extern void iput(struct inode *);
@@ -2164,6 +2164,7 @@ extern void __iget(struct inode * inode);
 extern void iget_failed(struct inode *);
 extern void clear_inode(struct inode *);
 extern void destroy_inode(struct inode *);
+extern void __destroy_inode(struct inode *);
 extern struct inode *new_inode(struct super_block *);
 extern int should_remove_suid(struct dentry *);
 extern int file_remove_suid(struct file *);