Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  autofs4: deal with autofs4_write/autofs4_write races
  autofs4: catatonic_mode vs. notify_daemon race
  autofs4: autofs4_wait() vs. autofs4_catatonic_mode() race
  hfsplus: creation of hidden dir on mount can fail
  block_dev: Suppress bdev_cache_init() kmemleak warninig
  fix shrink_dcache_parent() livelock
  coda: switch coda_cnode_make() to sane API as well, clean coda_lookup()
  coda: deal correctly with allocation failure from coda_cnode_makectl()
  securityfs: fix object creation races

12 files changed, 137 insertions, 214 deletions

diff --git a/fs/autofs4/autofs_i.h b/fs/autofs4/autofs_i.h
index 5869d4e974a9..d8d8e7ba6a1e 100644
--- a/fs/autofs4/autofs_i.h
+++ b/fs/autofs4/autofs_i.h
@@ -116,6 +116,7 @@ struct autofs_sb_info {
         int needs_reghost;
         struct super_block *sb;
         struct mutex wq_mutex;
+        struct mutex pipe_mutex;
         spinlock_t fs_lock;
         struct autofs_wait_queue *queues; /* Wait queue pointer */
         spinlock_t lookup_lock;
diff --git a/fs/autofs4/inode.c b/fs/autofs4/inode.c
index 2ba44c79d548..e16980b00b8d 100644
--- a/fs/autofs4/inode.c
+++ b/fs/autofs4/inode.c
@@ -225,6 +225,7 @@ int autofs4_fill_super(struct super_block *s, void *data, int silent)
         sbi->min_proto = 0;
         sbi->max_proto = 0;
         mutex_init(&sbi->wq_mutex);
+        mutex_init(&sbi->pipe_mutex);
         spin_lock_init(&sbi->fs_lock);
         sbi->queues = NULL;
         spin_lock_init(&sbi->lookup_lock);
diff --git a/fs/autofs4/waitq.c b/fs/autofs4/waitq.c
index e1fbdeef85db..9ef5b2914407 100644
--- a/fs/autofs4/waitq.c
+++ b/fs/autofs4/waitq.c
@@ -56,26 +56,27 @@ void autofs4_catatonic_mode(struct autofs_sb_info *sbi)
         mutex_unlock(&sbi->wq_mutex);
 }
 
-static int autofs4_write(struct file *file, const void *addr, int bytes)
+static int autofs4_write(struct autofs_sb_info *sbi,
+                         struct file *file, const void *addr, int bytes)
 {
         unsigned long sigpipe, flags;
         mm_segment_t fs;
         const char *data = (const char *)addr;
         ssize_t wr = 0;
 
-        /** WARNING: this is not safe for writing more than PIPE_BUF bytes! **/
-
         sigpipe = sigismember(&current->pending.signal, SIGPIPE);
 
         /* Save pointer to user space and point back to kernel space */
         fs = get_fs();
         set_fs(KERNEL_DS);
 
+        mutex_lock(&sbi->pipe_mutex);
         while (bytes &&
                (wr = file->f_op->write(file,data,bytes,&file->f_pos)) > 0) {
                 data += wr;
                 bytes -= wr;
         }
+        mutex_lock(&sbi->pipe_mutex);
 
         set_fs(fs);
 
@@ -110,6 +111,13 @@ static void autofs4_notify_daemon(struct autofs_sb_info *sbi,
 
         pkt.hdr.proto_version = sbi->version;
         pkt.hdr.type = type;
+        mutex_lock(&sbi->wq_mutex);
+
+        /* Check if we have become catatonic */
+        if (sbi->catatonic) {
+                mutex_unlock(&sbi->wq_mutex);
+                return;
+        }
         switch (type) {
         /* Kernel protocol v4 missing and expire packets */
         case autofs_ptype_missing:
@@ -163,22 +171,18 @@ static void autofs4_notify_daemon(struct autofs_sb_info *sbi,
         }
         default:
                 printk("autofs4_notify_daemon: bad type %d!\n", type);
+                mutex_unlock(&sbi->wq_mutex);
                 return;
         }
 
-        /* Check if we have become catatonic */
-        mutex_lock(&sbi->wq_mutex);
-        if (!sbi->catatonic) {
-                pipe = sbi->pipe;
-                get_file(pipe);
-        }
+        pipe = sbi->pipe;
+        get_file(pipe);
+
         mutex_unlock(&sbi->wq_mutex);
 
-        if (pipe) {
-                if (autofs4_write(pipe, &pkt, pktsz))
-                        autofs4_catatonic_mode(sbi);
-                fput(pipe);
-        }
+        if (autofs4_write(sbi, pipe, &pkt, pktsz))
+                autofs4_catatonic_mode(sbi);
+        fput(pipe);
 }
 
 static int autofs4_getpath(struct autofs_sb_info *sbi,
@@ -257,6 +261,9 @@ static int validate_request(struct autofs_wait_queue **wait,
         struct autofs_wait_queue *wq;
         struct autofs_info *ino;
 
+        if (sbi->catatonic)
+                return -ENOENT;
+
         /* Wait in progress, continue; */
         wq = autofs4_find_wait(sbi, qstr);
         if (wq) {
@@ -289,6 +296,9 @@ static int validate_request(struct autofs_wait_queue **wait,
                         if (mutex_lock_interruptible(&sbi->wq_mutex))
                                 return -EINTR;
 
+                        if (sbi->catatonic)
+                                return -ENOENT;
+
                         wq = autofs4_find_wait(sbi, qstr);
                         if (wq) {
                                 *wait = wq;
@@ -389,7 +399,7 @@ int autofs4_wait(struct autofs_sb_info *sbi, struct dentry *dentry,
 
         ret = validate_request(&wq, sbi, &qstr, dentry, notify);
         if (ret <= 0) {
-                if (ret == 0)
+                if (ret != -EINTR)
                         mutex_unlock(&sbi->wq_mutex);
                 kfree(qstr.name);
                 return ret;
diff --git a/fs/block_dev.c b/fs/block_dev.c
index 69a5b6fbee2b..afe74dda632b 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -25,7 +25,6 @@
 #include <linux/uio.h>
 #include <linux/namei.h>
 #include <linux/log2.h>
-#include <linux/kmemleak.h>
 #include <linux/cleancache.h>
 #include <asm/uaccess.h>
 #include "internal.h"
@@ -521,7 +520,7 @@ static struct super_block *blockdev_superblock __read_mostly;
 void __init bdev_cache_init(void)
 {
         int err;
-        struct vfsmount *bd_mnt;
+        static struct vfsmount *bd_mnt;
 
         bdev_cachep = kmem_cache_create("bdev_cache", sizeof(struct bdev_inode),
                         0, (SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT|
@@ -533,12 +532,7 @@ void __init bdev_cache_init(void)
         bd_mnt = kern_mount(&bd_type);
         if (IS_ERR(bd_mnt))
                 panic("Cannot create bdev pseudo-fs");
-        /*
-         * This vfsmount structure is only used to obtain the
-         * blockdev_superblock, so tell kmemleak not to report it.
-         */
-        kmemleak_not_leak(bd_mnt);
-        blockdev_superblock = bd_mnt->mnt_sb;   /* For writeback */
+        blockdev_superblock = bd_mnt->mnt_sb;   /* For writeback */
 }
 
 /*
diff --git a/fs/coda/cnode.c b/fs/coda/cnode.c
index 6475877b0763..911cf30d057d 100644
--- a/fs/coda/cnode.c
+++ b/fs/coda/cnode.c
@@ -88,24 +88,21 @@ struct inode * coda_iget(struct super_block * sb, struct CodaFid * fid,
    - link the two up if this is needed
    - fill in the attributes
 */
-int coda_cnode_make(struct inode **inode, struct CodaFid *fid, struct super_block *sb)
+struct inode *coda_cnode_make(struct CodaFid *fid, struct super_block *sb)
 {
         struct coda_vattr attr;
+        struct inode *inode;
         int error;
         
         /* We get inode numbers from Venus -- see venus source */
         error = venus_getattr(sb, fid, &attr);
-        if ( error ) {
-            *inode = NULL;
-            return error;
-        } 
+        if (error)
+                return ERR_PTR(error);
 
-        *inode = coda_iget(sb, fid, &attr);
-        if ( IS_ERR(*inode) ) {
+        inode = coda_iget(sb, fid, &attr);
+        if (IS_ERR(inode))
                 printk("coda_cnode_make: coda_iget failed\n");
-                return PTR_ERR(*inode);
-        }
-        return 0;
+        return inode;
 }
 
 
@@ -156,19 +153,16 @@ struct inode *coda_fid_to_inode(struct CodaFid *fid, struct super_block *sb)
 }
 
 /* the CONTROL inode is made without asking attributes from Venus */
-int coda_cnode_makectl(struct inode **inode, struct super_block *sb)
+struct inode *coda_cnode_makectl(struct super_block *sb)
 {
-        int error = -ENOMEM;
-
-        *inode = new_inode(sb);
-        if (*inode) {
-                (*inode)->i_ino = CTL_INO;
-                (*inode)->i_op = &coda_ioctl_inode_operations;
-                (*inode)->i_fop = &coda_ioctl_operations;
-                (*inode)->i_mode = 0444;
-                error = 0;
+        struct inode *inode = new_inode(sb);
+        if (inode) {
+                inode->i_ino = CTL_INO;
+                inode->i_op = &coda_ioctl_inode_operations;
+                inode->i_fop = &coda_ioctl_operations;
+                inode->i_mode = 0444;
+                return inode;
         }
-
-        return error;
+        return ERR_PTR(-ENOMEM);
 }
 
diff --git a/fs/coda/coda_fs_i.h b/fs/coda/coda_fs_i.h
index e35071b1de0e..b24fdfd8a3f0 100644
--- a/fs/coda/coda_fs_i.h
+++ b/fs/coda/coda_fs_i.h
@@ -49,9 +49,9 @@ struct coda_file_info {
 #define C_DYING       0x4   /* from venus (which died) */
 #define C_PURGE       0x8
 
-int coda_cnode_make(struct inode **, struct CodaFid *, struct super_block *);
+struct inode *coda_cnode_make(struct CodaFid *, struct super_block *);
 struct inode *coda_iget(struct super_block *sb, struct CodaFid *fid, struct coda_vattr *attr);
-int coda_cnode_makectl(struct inode **inode, struct super_block *sb);
+struct inode *coda_cnode_makectl(struct super_block *sb);
 struct inode *coda_fid_to_inode(struct CodaFid *fid, struct super_block *sb);
 void coda_replace_fid(struct inode *, struct CodaFid *, struct CodaFid *);
 
diff --git a/fs/coda/dir.c b/fs/coda/dir.c
index 83d2fd8ec24b..177515829062 100644
--- a/fs/coda/dir.c
+++ b/fs/coda/dir.c
@@ -96,12 +96,11 @@ const struct file_operations coda_dir_operations = {
 /* access routines: lookup, readlink, permission */
 static struct dentry *coda_lookup(struct inode *dir, struct dentry *entry, struct nameidata *nd)
 {
-        struct inode *inode = NULL;
-        struct CodaFid resfid = { { 0, } };
-        int type = 0;
-        int error = 0;
+        struct super_block *sb = dir->i_sb;
         const char *name = entry->d_name.name;
         size_t length = entry->d_name.len;
+        struct inode *inode;
+        int type = 0;
 
         if (length > CODA_MAXNAMLEN) {
                 printk(KERN_ERR "name too long: lookup, %s (%*s)\n",
@@ -111,23 +110,21 @@ static struct dentry *coda_lookup(struct inode *dir, struct dentry *entry, struc
 
         /* control object, create inode on the fly */
         if (coda_isroot(dir) && coda_iscontrol(name, length)) {
-                error = coda_cnode_makectl(&inode, dir->i_sb);
+                inode = coda_cnode_makectl(sb);
                 type = CODA_NOCACHE;
-                goto exit;
+        } else {
+                struct CodaFid fid = { { 0, } };
+                int error = venus_lookup(sb, coda_i2f(dir), name, length,
+                                     &type, &fid);
+                inode = !error ? coda_cnode_make(&fid, sb) : ERR_PTR(error);
         }
 
-        error = venus_lookup(dir->i_sb, coda_i2f(dir), name, length,
-                             &type, &resfid);
-        if (!error)
-                error = coda_cnode_make(&inode, &resfid, dir->i_sb);
-
-        if (error && error != -ENOENT)
-                return ERR_PTR(error);
-
-exit:
-        if (inode && (type & CODA_NOCACHE))
+        if (!IS_ERR(inode) && (type & CODA_NOCACHE))
                 coda_flag_inode(inode, C_VATTR | C_PURGE);
 
+        if (inode == ERR_PTR(-ENOENT))
+                inode = NULL;
+
         return d_splice_alias(inode, entry);
 }
 
diff --git a/fs/coda/inode.c b/fs/coda/inode.c
index 1c08a8cd673a..5e2e1b3f068d 100644
--- a/fs/coda/inode.c
+++ b/fs/coda/inode.c
@@ -204,10 +204,12 @@ static int coda_fill_super(struct super_block *sb, void *data, int silent)
         printk("coda_read_super: rootfid is %s\n", coda_f2s(&fid));
         
         /* make root inode */
-        error = coda_cnode_make(&root, &fid, sb);
-        if ( error || !root ) {
-            printk("Failure of coda_cnode_make for root: error %d\n", error);
-            goto error;
+        root = coda_cnode_make(&fid, sb);
+        if (IS_ERR(root)) {
+                error = PTR_ERR(root);
+                printk("Failure of coda_cnode_make for root: error %d\n", error);
+                root = NULL;
+                goto error;
         } 
 
         printk("coda_read_super: rootinode is %ld dev %s\n", 
diff --git a/fs/dcache.c b/fs/dcache.c
index 3c6d3113a255..616fedff011a 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -243,6 +243,7 @@ static void dentry_lru_add(struct dentry *dentry)
 static void __dentry_lru_del(struct dentry *dentry)
 {
         list_del_init(&dentry->d_lru);
+        dentry->d_flags &= ~DCACHE_SHRINK_LIST;
         dentry->d_sb->s_nr_dentry_unused--;
         dentry_stat.nr_unused--;
 }
@@ -806,6 +807,7 @@ relock:
                         spin_unlock(&dentry->d_lock);
                 } else {
                         list_move_tail(&dentry->d_lru, &tmp);
+                        dentry->d_flags |= DCACHE_SHRINK_LIST;
                         spin_unlock(&dentry->d_lock);
                         if (!--count)
                                 break;
@@ -1097,14 +1099,19 @@ resume:
 
                 /*
                  * move only zero ref count dentries to the dispose list.
+                 *
+                 * Those which are presently on the shrink list, being processed
+                 * by shrink_dentry_list(), shouldn't be moved.  Otherwise the
+                 * loop in shrink_dcache_parent() might not make any progress
+                 * and loop forever.
                  */
-                if (!dentry->d_count) {
+                if (dentry->d_count) {
+                        dentry_lru_del(dentry);
+                } else if (!(dentry->d_flags & DCACHE_SHRINK_LIST)) {
                         dentry_lru_move_list(dentry, dispose);
+                        dentry->d_flags |= DCACHE_SHRINK_LIST;
                         found++;
-                } else {
-                        dentry_lru_del(dentry);
                 }
-
                 /*
                  * We can return to the caller if we have found some (this
                  * ensures forward progress). We'll be coming back to find
diff --git a/fs/hfsplus/super.c b/fs/hfsplus/super.c
index edf0a801446b..427682ca9e48 100644
--- a/fs/hfsplus/super.c
+++ b/fs/hfsplus/super.c
@@ -499,9 +499,16 @@ static int hfsplus_fill_super(struct super_block *sb, void *data, int silent)
                 if (!sbi->hidden_dir) {
                         mutex_lock(&sbi->vh_mutex);
                         sbi->hidden_dir = hfsplus_new_inode(sb, S_IFDIR);
-                        hfsplus_create_cat(sbi->hidden_dir->i_ino, root, &str,
-                                           sbi->hidden_dir);
+                        if (!sbi->hidden_dir) {
+                                mutex_unlock(&sbi->vh_mutex);
+                                err = -ENOMEM;
+                                goto out_put_root;
+                        }
+                        err = hfsplus_create_cat(sbi->hidden_dir->i_ino, root,
+                                                 &str, sbi->hidden_dir);
                         mutex_unlock(&sbi->vh_mutex);
+                        if (err)
+                                goto out_put_hidden_dir;
 
                         hfsplus_mark_inode_dirty(sbi->hidden_dir,
                                                  HFSPLUS_I_CAT_DIRTY);
diff --git a/include/linux/dcache.h b/include/linux/dcache.h
index a47bda5f76db..31f73220e7d7 100644
--- a/include/linux/dcache.h
+++ b/include/linux/dcache.h
@@ -203,6 +203,7 @@ struct dentry_operations {
 
 #define DCACHE_CANT_MOUNT       0x0100
 #define DCACHE_GENOCIDE         0x0200
+#define DCACHE_SHRINK_LIST      0x0400
 
 #define DCACHE_NFSFS_RENAMED    0x1000
      /* this dentry has been "silly renamed" and has to be deleted on the last
diff --git a/security/inode.c b/security/inode.c
index 90a70a67d835..43ce6e19015f 100644
--- a/security/inode.c
+++ b/security/inode.c
@@ -25,100 +25,6 @@
 static struct vfsmount *mount;
 static int mount_count;
 
-/*
- * TODO:
- *   I think I can get rid of these default_file_ops, but not quite sure...
- */
-static ssize_t default_read_file(struct file *file, char __user *buf,
-                                 size_t count, loff_t *ppos)
-{
-        return 0;
-}
-
-static ssize_t default_write_file(struct file *file, const char __user *buf,
-                                   size_t count, loff_t *ppos)
-{
-        return count;
-}
-
-static int default_open(struct inode *inode, struct file *file)
-{
-        if (inode->i_private)
-                file->private_data = inode->i_private;
-
-        return 0;
-}
-
-static const struct file_operations default_file_ops = {
-        .read =         default_read_file,
-        .write =        default_write_file,
-        .open =         default_open,
-        .llseek =       noop_llseek,
-};
-
-static struct inode *get_inode(struct super_block *sb, umode_t mode, dev_t dev)
-{
-        struct inode *inode = new_inode(sb);
-
-        if (inode) {
-                inode->i_ino = get_next_ino();
-                inode->i_mode = mode;
-                inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
-                switch (mode & S_IFMT) {
-                default:
-                        init_special_inode(inode, mode, dev);
-                        break;
-                case S_IFREG:
-                        inode->i_fop = &default_file_ops;
-                        break;
-                case S_IFDIR:
-                        inode->i_op = &simple_dir_inode_operations;
-                        inode->i_fop = &simple_dir_operations;
-
-                        /* directory inodes start off with i_nlink == 2 (for "." entry) */
-                        inc_nlink(inode);
-                        break;
-                }
-        }
-        return inode;
-}
-
-/* SMP-safe */
-static int mknod(struct inode *dir, struct dentry *dentry,
-                         umode_t mode, dev_t dev)
-{
-        struct inode *inode;
-        int error = -ENOMEM;
-
-        if (dentry->d_inode)
-                return -EEXIST;
-
-        inode = get_inode(dir->i_sb, mode, dev);
-        if (inode) {
-                d_instantiate(dentry, inode);
-                dget(dentry);
-                error = 0;
-        }
-        return error;
-}
-
-static int mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
-{
-        int res;
-
-        mode = (mode & (S_IRWXUGO | S_ISVTX)) | S_IFDIR;
-        res = mknod(dir, dentry, mode, 0);
-        if (!res)
-                inc_nlink(dir);
-        return res;
-}
-
-static int create(struct inode *dir, struct dentry *dentry, umode_t mode)
-{
-        mode = (mode & S_IALLUGO) | S_IFREG;
-        return mknod(dir, dentry, mode, 0);
-}
-
 static inline int positive(struct dentry *dentry)
 {
         return dentry->d_inode && !d_unhashed(dentry);
@@ -145,38 +51,6 @@ static struct file_system_type fs_type = {
         .kill_sb =      kill_litter_super,
 };
 
-static int create_by_name(const char *name, umode_t mode,
-                          struct dentry *parent,
-                          struct dentry **dentry)
-{
-        int error = 0;
-
-        *dentry = NULL;
-
-        /* If the parent is not specified, we create it in the root.
-         * We need the root dentry to do this, which is in the super
-         * block. A pointer to that is in the struct vfsmount that we
-         * have around.
-         */
-        if (!parent)
-                parent = mount->mnt_root;
-
-        mutex_lock(&parent->d_inode->i_mutex);
-        *dentry = lookup_one_len(name, parent, strlen(name));
-        if (!IS_ERR(*dentry)) {
-                if (S_ISDIR(mode))
-                        error = mkdir(parent->d_inode, *dentry, mode);
-                else
-                        error = create(parent->d_inode, *dentry, mode);
-                if (error)
-                        dput(*dentry);
-        } else
-                error = PTR_ERR(*dentry);
-        mutex_unlock(&parent->d_inode->i_mutex);
-
-        return error;
-}
-
 /**
  * securityfs_create_file - create a file in the securityfs filesystem
  *
@@ -209,31 +83,66 @@ struct dentry *securityfs_create_file(const char *name, umode_t mode,
                                    struct dentry *parent, void *data,
                                    const struct file_operations *fops)
 {
-        struct dentry *dentry = NULL;
+        struct dentry *dentry;
+        int is_dir = S_ISDIR(mode);
+        struct inode *dir, *inode;
         int error;
 
+        if (!is_dir) {
+                BUG_ON(!fops);
+                mode = (mode & S_IALLUGO) | S_IFREG;
+        }
+
         pr_debug("securityfs: creating file '%s'\n",name);
 
         error = simple_pin_fs(&fs_type, &mount, &mount_count);
-        if (error) {
-                dentry = ERR_PTR(error);
-                goto exit;
+        if (error)
+                return ERR_PTR(error);
+
+        if (!parent)
+                parent = mount->mnt_root;
+
+        dir = parent->d_inode;
+
+        mutex_lock(&dir->i_mutex);
+        dentry = lookup_one_len(name, parent, strlen(name));
+        if (IS_ERR(dentry))
+                goto out;
+
+        if (dentry->d_inode) {
+                error = -EEXIST;
+                goto out1;
         }
 
-        error = create_by_name(name, mode, parent, &dentry);
-        if (error) {
-                dentry = ERR_PTR(error);
-                simple_release_fs(&mount, &mount_count);
-                goto exit;
+        inode = new_inode(dir->i_sb);
+        if (!inode) {
+                error = -ENOMEM;
+                goto out1;
         }
 
-        if (dentry->d_inode) {
-                if (fops)
-                        dentry->d_inode->i_fop = fops;
-                if (data)
-                        dentry->d_inode->i_private = data;
+        inode->i_ino = get_next_ino();
+        inode->i_mode = mode;
+        inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
+        inode->i_private = data;
+        if (is_dir) {
+                inode->i_op = &simple_dir_inode_operations;
+                inode->i_fop = &simple_dir_operations;
+                inc_nlink(inode);
+                inc_nlink(dir);
+        } else {
+                inode->i_fop = fops;
         }
-exit:
+        d_instantiate(dentry, inode);
+        dget(dentry);
+        mutex_unlock(&dir->i_mutex);
+        return dentry;
+
+out1:
+        dput(dentry);
+        dentry = ERR_PTR(error);
+out:
+        mutex_unlock(&dir->i_mutex);
+        simple_release_fs(&mount, &mount_count);
         return dentry;
 }
 EXPORT_SYMBOL_GPL(securityfs_create_file);