From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Fri, 25 Dec 2020 18:54:29 +0000 (-0800)
Subject: Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
X-Git-Tag: microblaze-v5.12~18
X-Git-Url: http://git.monstr.eu/?p=linux-2.6-microblaze.git;a=commitdiff_plain;h=7bb5226c8a4bbf26a9ededc90532b0ad539d2017;hp=-c

Merge branch 'work.misc' of git://git./linux/kernel/git/viro/vfs

Pull misc vfs updates from Al Viro:
 "Assorted patches from previous cycle(s)..."

* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  fix hostfs_open() use of ->f_path.dentry
  Make sure that make_create_in_sticky() never sees uninitialized value of dir_mode
  fs: Kill DCACHE_DONTCACHE dentry even if DCACHE_REFERENCED is set
  fs: Handle I_DONTCACHE in iput_final() instead of generic_drop_inode()
  fs/namespace.c: WARN if mnt_count has become negative
---

7bb5226c8a4bbf26a9ededc90532b0ad539d2017
diff --combined fs/inode.c
index cb008acf0efd,5eea9912a0b9..6442d97d9a4a
--- a/fs/inode.c
+++ b/fs/inode.c
@@@ -155,6 -155,7 +155,6 @@@ int inode_init_always(struct super_bloc
  	inode->i_bytes = 0;
  	inode->i_generation = 0;
  	inode->i_pipe = NULL;
 -	inode->i_bdev = NULL;
  	inode->i_cdev = NULL;
  	inode->i_link = NULL;
  	inode->i_dir_seq = 0;
@@@ -579,6 -580,8 +579,6 @@@ static void evict(struct inode *inode
  		truncate_inode_pages_final(&inode->i_data);
  		clear_inode(inode);
  	}
 -	if (S_ISBLK(inode->i_mode) && inode->i_bdev)
 -		bd_forget(inode);
  	if (S_ISCHR(inode->i_mode) && inode->i_cdev)
  		cd_forget(inode);
  
@@@ -1624,7 -1627,9 +1624,9 @@@ static void iput_final(struct inode *in
  	else
  		drop = generic_drop_inode(inode);
  
- 	if (!drop && (sb->s_flags & SB_ACTIVE)) {
+ 	if (!drop &&
+ 	    !(inode->i_state & I_DONTCACHE) &&
+ 	    (sb->s_flags & SB_ACTIVE)) {
  		inode_add_lru(inode);
  		spin_unlock(&inode->i_lock);
  		return;
diff --combined fs/namei.c
index 03d0e11e4f36,fc193c684a57..78443a85480a
--- a/fs/namei.c
+++ b/fs/namei.c
@@@ -2114,8 -2114,10 +2114,10 @@@ static int link_path_walk(const char *n
  		return PTR_ERR(name);
  	while (*name=='/')
  		name++;
- 	if (!*name)
+ 	if (!*name) {
+ 		nd->dir_mode = 0; // short-circuit the 'hardening' idiocy
  		return 0;
+ 	}
  
  	/* At this point we know we have a real path component. */
  	for(;;) {
@@@ -4346,8 -4348,8 +4348,8 @@@ out
  }
  EXPORT_SYMBOL(vfs_rename);
  
 -static int do_renameat2(int olddfd, const char __user *oldname, int newdfd,
 -			const char __user *newname, unsigned int flags)
 +int do_renameat2(int olddfd, struct filename *from, int newdfd,
 +		 struct filename *to, unsigned int flags)
  {
  	struct dentry *old_dentry, *new_dentry;
  	struct dentry *trap;
@@@ -4355,30 -4357,32 +4357,30 @@@
  	struct qstr old_last, new_last;
  	int old_type, new_type;
  	struct inode *delegated_inode = NULL;
 -	struct filename *from;
 -	struct filename *to;
  	unsigned int lookup_flags = 0, target_flags = LOOKUP_RENAME_TARGET;
  	bool should_retry = false;
 -	int error;
 +	int error = -EINVAL;
  
  	if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE | RENAME_WHITEOUT))
 -		return -EINVAL;
 +		goto put_both;
  
  	if ((flags & (RENAME_NOREPLACE | RENAME_WHITEOUT)) &&
  	    (flags & RENAME_EXCHANGE))
 -		return -EINVAL;
 +		goto put_both;
  
  	if (flags & RENAME_EXCHANGE)
  		target_flags = 0;
  
  retry:
 -	from = filename_parentat(olddfd, getname(oldname), lookup_flags,
 -				&old_path, &old_last, &old_type);
 +	from = filename_parentat(olddfd, from, lookup_flags, &old_path,
 +					&old_last, &old_type);
  	if (IS_ERR(from)) {
  		error = PTR_ERR(from);
 -		goto exit;
 +		goto put_new;
  	}
  
 -	to = filename_parentat(newdfd, getname(newname), lookup_flags,
 -				&new_path, &new_last, &new_type);
 +	to = filename_parentat(newdfd, to, lookup_flags, &new_path, &new_last,
 +				&new_type);
  	if (IS_ERR(to)) {
  		error = PTR_ERR(to);
  		goto exit1;
@@@ -4471,40 -4475,34 +4473,40 @@@ exit2
  	if (retry_estale(error, lookup_flags))
  		should_retry = true;
  	path_put(&new_path);
 -	putname(to);
  exit1:
  	path_put(&old_path);
 -	putname(from);
  	if (should_retry) {
  		should_retry = false;
  		lookup_flags |= LOOKUP_REVAL;
  		goto retry;
  	}
 -exit:
 +put_both:
 +	if (!IS_ERR(from))
 +		putname(from);
 +put_new:
 +	if (!IS_ERR(to))
 +		putname(to);
  	return error;
  }
  
  SYSCALL_DEFINE5(renameat2, int, olddfd, const char __user *, oldname,
  		int, newdfd, const char __user *, newname, unsigned int, flags)
  {
 -	return do_renameat2(olddfd, oldname, newdfd, newname, flags);
 +	return do_renameat2(olddfd, getname(oldname), newdfd, getname(newname),
 +				flags);
  }
  
  SYSCALL_DEFINE4(renameat, int, olddfd, const char __user *, oldname,
  		int, newdfd, const char __user *, newname)
  {
 -	return do_renameat2(olddfd, oldname, newdfd, newname, 0);
 +	return do_renameat2(olddfd, getname(oldname), newdfd, getname(newname),
 +				0);
  }
  
  SYSCALL_DEFINE2(rename, const char __user *, oldname, const char __user *, newname)
  {
 -	return do_renameat2(AT_FDCWD, oldname, AT_FDCWD, newname, 0);
 +	return do_renameat2(AT_FDCWD, getname(oldname), AT_FDCWD,
 +				getname(newname), 0);
  }
  
  int readlink_copy(char __user *buffer, int buflen, const char *link)
diff --combined fs/namespace.c
index 2b681f65ca04,93006abe7946..d2db7dfe232b
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@@ -156,10 -156,10 +156,10 @@@ static inline void mnt_add_count(struc
  /*
   * vfsmount lock must be held for write
   */
- unsigned int mnt_get_count(struct mount *mnt)
+ int mnt_get_count(struct mount *mnt)
  {
  #ifdef CONFIG_SMP
- 	unsigned int count = 0;
+ 	int count = 0;
  	int cpu;
  
  	for_each_possible_cpu(cpu) {
@@@ -1139,6 -1139,7 +1139,7 @@@ static DECLARE_DELAYED_WORK(delayed_mnt
  static void mntput_no_expire(struct mount *mnt)
  {
  	LIST_HEAD(list);
+ 	int count;
  
  	rcu_read_lock();
  	if (likely(READ_ONCE(mnt->mnt_ns))) {
@@@ -1162,7 -1163,9 +1163,9 @@@
  	 */
  	smp_mb();
  	mnt_add_count(mnt, -1);
- 	if (mnt_get_count(mnt)) {
+ 	count = mnt_get_count(mnt);
+ 	if (count != 0) {
+ 		WARN_ON(count < 0);
  		rcu_read_unlock();
  		unlock_mount_hash();
  		return;
@@@ -3274,7 -3277,7 +3277,7 @@@ static struct mnt_namespace *alloc_mnt_
  	new_ns->ns.ops = &mntns_operations;
  	if (!anon)
  		new_ns->seq = atomic64_add_return(1, &mnt_ns_seq);
 -	atomic_set(&new_ns->count, 1);
 +	refcount_set(&new_ns->ns.count, 1);
  	INIT_LIST_HEAD(&new_ns->list);
  	init_waitqueue_head(&new_ns->poll);
  	spin_lock_init(&new_ns->ns_lock);
@@@ -3848,7 -3851,7 +3851,7 @@@ void __init mnt_init(void
  
  void put_mnt_ns(struct mnt_namespace *ns)
  {
 -	if (!atomic_dec_and_test(&ns->count))
 +	if (!refcount_dec_and_test(&ns->ns.count))
  		return;
  	drop_collected_mounts(&ns->root->mnt);
  	free_mnt_ns(ns);
diff --combined include/linux/fs.h
index ad4cf1bae586,8bde32cf9711..fd47deea7c17
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@@ -696,6 -696,7 +696,6 @@@ struct inode 
  	struct list_head	i_devices;
  	union {
  		struct pipe_inode_info	*i_pipe;
 -		struct block_device	*i_bdev;
  		struct cdev		*i_cdev;
  		char			*i_link;
  		unsigned		i_dir_seq;
@@@ -922,7 -923,7 +922,7 @@@ struct file 
  	const struct file_operations	*f_op;
  
  	/*
 -	 * Protects f_ep_links, f_flags.
 +	 * Protects f_ep, f_flags.
  	 * Must not be taken from IRQ context.
  	 */
  	spinlock_t		f_lock;
@@@ -945,7 -946,8 +945,7 @@@
  
  #ifdef CONFIG_EPOLL
  	/* Used by fs/eventpoll.c to link all the hooks to this file */
 -	struct list_head	f_ep_links;
 -	struct list_head	f_tfile_llink;
 +	struct hlist_head	*f_ep;
  #endif /* #ifdef CONFIG_EPOLL */
  	struct address_space	*f_mapping;
  	errseq_t		f_wb_err;
@@@ -1407,7 -1409,7 +1407,7 @@@ enum 
  
  struct sb_writers {
  	int				frozen;		/* Is sb frozen? */
 -	wait_queue_head_t		wait_unfrozen;	/* for get_super_thawed() */
 +	wait_queue_head_t		wait_unfrozen;	/* wait for thaw */
  	struct percpu_rw_semaphore	rw_sem[SB_FREEZE_LEVELS];
  };
  
@@@ -2876,8 -2878,7 +2876,7 @@@ extern int inode_needs_sync(struct inod
  extern int generic_delete_inode(struct inode *inode);
  static inline int generic_drop_inode(struct inode *inode)
  {
- 	return !inode->i_nlink || inode_unhashed(inode) ||
- 		(inode->i_state & I_DONTCACHE);
+ 	return !inode->i_nlink || inode_unhashed(inode);
  }
  extern void d_mark_dontcache(struct inode *inode);
  
@@@ -3130,6 -3131,8 +3129,6 @@@ extern struct file_system_type *get_fil
  extern void put_filesystem(struct file_system_type *fs);
  extern struct file_system_type *get_fs_type(const char *name);
  extern struct super_block *get_super(struct block_device *);
 -extern struct super_block *get_super_thawed(struct block_device *);
 -extern struct super_block *get_super_exclusive_thawed(struct block_device *bdev);
  extern struct super_block *get_active_super(struct block_device *bdev);
  extern void drop_super(struct super_block *sb);
  extern void drop_super_exclusive(struct super_block *sb);
@@@ -3198,7 -3201,6 +3197,7 @@@ extern int generic_ci_d_hash(const stru
  extern int generic_ci_d_compare(const struct dentry *dentry, unsigned int len,
  				const char *str, const struct qstr *name);
  #endif
 +extern void generic_set_encrypted_ci_d_ops(struct dentry *dentry);
  
  #ifdef CONFIG_MIGRATION
  extern int buffer_migrate_page(struct address_space *,
@@@ -3227,7 -3229,7 +3226,7 @@@ static inline bool vma_is_fsdax(struct 
  {
  	struct inode *inode;
  
 -	if (!vma->vm_file)
 +	if (!IS_ENABLED(CONFIG_FS_DAX) || !vma->vm_file)
  		return false;
  	if (!vma_is_dax(vma))
  		return false;