[PATCH 2/5] fs: Rename file_remove_suid() to file_remove_privs()

From: Jan Kara <jack@suse.cz>
To: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
	linux-fsdevel@vger.kernel.org, dchinner@redhat.com,
	Serge Hallyn <serge.hallyn@canonical.com>,
	linux-security-module@vger.kernel.org, Jan Kara <jack@suse.cz>
Subject: [PATCH 2/5] fs: Rename file_remove_suid() to file_remove_privs()
Date: Tue, 19 May 2015 11:46:40 +0200	[thread overview]
Message-ID: <1432028803-32296-3-git-send-email-jack@suse.cz> (raw)
In-Reply-To: <1432028803-32296-1-git-send-email-jack@suse.cz>

file_remove_suid() is a misnomer since it removes also security related
xattrs and sets S_NOSEC flag. Also should_remove_suid() tells something
else than whether file_remove_suid() call is necessary which leads to
bugs.

Signed-off-by: Jan Kara <jack@suse.cz>
---
 fs/btrfs/file.c    |  2 +-
 fs/ceph/file.c     |  2 +-
 fs/fuse/file.c     |  2 +-
 fs/inode.c         | 13 ++++++++-----
 fs/ntfs/file.c     |  2 +-
 fs/xfs/xfs_file.c  |  2 +-
 include/linux/fs.h |  2 +-
 mm/filemap.c       |  2 +-
 8 files changed, 15 insertions(+), 12 deletions(-)

diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index b072e17479aa..86f97282779a 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -1748,7 +1748,7 @@ static ssize_t btrfs_file_write_iter(struct kiocb *iocb,
 	}
 
 	current->backing_dev_info = inode_to_bdi(inode);
-	err = file_remove_suid(file);
+	err = file_remove_privs(file);
 	if (err) {
 		mutex_unlock(&inode->i_mutex);
 		goto out;
diff --git a/fs/ceph/file.c b/fs/ceph/file.c
index 3b6b522b4b31..e55fe32c6224 100644
--- a/fs/ceph/file.c
+++ b/fs/ceph/file.c
@@ -959,7 +959,7 @@ static ssize_t ceph_write_iter(struct kiocb *iocb, struct iov_iter *from)
 
 	pos = iocb->ki_pos;
 	count = iov_iter_count(from);
-	err = file_remove_suid(file);
+	err = file_remove_privs(file);
 	if (err)
 		goto out;
 
diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index 5ef05b5c4cff..1344647965dc 100644
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -1169,7 +1169,7 @@ static ssize_t fuse_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
 	if (err <= 0)
 		goto out;
 
-	err = file_remove_suid(file);
+	err = file_remove_privs(file);
 	if (err)
 		goto out;
 
diff --git a/fs/inode.c b/fs/inode.c
index 6e342cadef81..aa140f7bf336 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -1672,7 +1672,11 @@ static int __remove_suid(struct dentry *dentry, int kill)
 	return notify_change(dentry, &newattrs, NULL);
 }
 
-int file_remove_suid(struct file *file)
+/*
+ * Remove special file priviledges (suid, security tags) when file is written
+ * to or truncated.
+ */
+int file_remove_privs(struct file *file)
 {
 	struct dentry *dentry = file->f_path.dentry;
 	struct inode *inode = d_inode(dentry);
@@ -1698,7 +1702,7 @@ int file_remove_suid(struct file *file)
 
 	return error;
 }
-EXPORT_SYMBOL(file_remove_suid);
+EXPORT_SYMBOL(file_remove_privs);
 
 /**
  *	file_update_time	-	update mtime and ctime time
@@ -1953,9 +1957,8 @@ EXPORT_SYMBOL(inode_dio_wait);
  * inode is being instantiated).  The reason for the cmpxchg() loop
  * --- which wouldn't be necessary if all code paths which modify
  * i_flags actually followed this rule, is that there is at least one
- * code path which doesn't today --- for example,
- * __generic_file_aio_write() calls file_remove_suid() without holding
- * i_mutex --- so we use cmpxchg() out of an abundance of caution.
+ * code path which doesn't today so we use cmpxchg() out of an abundance
+ * of caution.
  *
  * In the long run, i_mutex is overkill, and we should probably look
  * at using the i_lock spinlock to protect i_flags, and then make sure
diff --git a/fs/ntfs/file.c b/fs/ntfs/file.c
index 7bb487e663b4..182bb93aa79c 100644
--- a/fs/ntfs/file.c
+++ b/fs/ntfs/file.c
@@ -382,7 +382,7 @@ static ssize_t ntfs_prepare_file_for_write(struct kiocb *iocb,
 	base_ni = ni;
 	if (NInoAttr(ni))
 		base_ni = ni->ext.base_ntfs_ino;
-	err = file_remove_suid(file);
+	err = file_remove_privs(file);
 	if (unlikely(err))
 		goto out;
 	/*
diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index 8121e75352ee..f3e4fbb59985 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -623,7 +623,7 @@ restart:
 	 * setgid bits if the process is not being run by root.  This keeps
 	 * people from modifying setuid and setgid binaries.
 	 */
-	return file_remove_suid(file);
+	return file_remove_privs(file);
 }
 
 /*
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 35ec87e490b1..082f66274e63 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2552,7 +2552,7 @@ extern struct inode *new_inode_pseudo(struct super_block *sb);
 extern struct inode *new_inode(struct super_block *sb);
 extern void free_inode_nonrcu(struct inode *inode);
 extern int should_remove_suid(struct dentry *);
-extern int file_remove_suid(struct file *);
+extern int file_remove_privs(struct file *);
 
 extern void __insert_inode_hash(struct inode *, unsigned long hashval);
 static inline void insert_inode_hash(struct inode *inode)
diff --git a/mm/filemap.c b/mm/filemap.c
index 6bf5e42d560a..f851e36802d5 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -2536,7 +2536,7 @@ ssize_t __generic_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
 
 	/* We can write back this queue in page reclaim */
 	current->backing_dev_info = inode_to_bdi(inode);
-	err = file_remove_suid(file);
+	err = file_remove_privs(file);
 	if (err)
 		goto out;
 
-- 
2.1.4

