fs: move file_remove_suid() to fs/inode.c

file_remove_suid() is a generic function operates on struct file,
it almost has no relations with file mapping, so move it to fs/inode.c.

Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

diff --git a/fs/inode.c b/fs/inode.c
index 183ddd6cda7115fda642e7b06a5414cbe25d4c77..a79555e492e0751989c1dacebf4a62910798fcc8 100644 (file)
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -1530,6 +1530,71 @@ void touch_atime(struct path *path)
 }
 EXPORT_SYMBOL(touch_atime);
 
+/*
+ * The logic we want is
+ *
+ *     if suid or (sgid and xgrp)
+ *             remove privs
+ */
+int should_remove_suid(struct dentry *dentry)
+{
+       umode_t mode = dentry->d_inode->i_mode;
+       int kill = 0;
+
+       /* suid always must be killed */
+       if (unlikely(mode & S_ISUID))
+               kill = ATTR_KILL_SUID;
+
+       /*
+        * sgid without any exec bits is just a mandatory locking mark; leave
+        * it alone.  If some exec bits are set, it's a real sgid; kill it.
+        */
+       if (unlikely((mode & S_ISGID) && (mode & S_IXGRP)))
+               kill |= ATTR_KILL_SGID;
+
+       if (unlikely(kill && !capable(CAP_FSETID) && S_ISREG(mode)))
+               return kill;
+
+       return 0;
+}
+EXPORT_SYMBOL(should_remove_suid);
+
+static int __remove_suid(struct dentry *dentry, int kill)
+{
+       struct iattr newattrs;
+
+       newattrs.ia_valid = ATTR_FORCE | kill;
+       return notify_change(dentry, &newattrs);
+}
+
+int file_remove_suid(struct file *file)
+{
+       struct dentry *dentry = file->f_path.dentry;
+       struct inode *inode = dentry->d_inode;
+       int killsuid;
+       int killpriv;
+       int error = 0;
+
+       /* Fast path for nothing security related */
+       if (IS_NOSEC(inode))
+               return 0;
+
+       killsuid = should_remove_suid(dentry);
+       killpriv = security_inode_need_killpriv(dentry);
+
+       if (killpriv < 0)
+               return killpriv;
+       if (killpriv)
+               error = security_inode_killpriv(dentry);
+       if (!error && killsuid)
+               error = __remove_suid(dentry, killsuid);
+       if (!error && (inode->i_sb->s_flags & MS_NOSEC))
+               inode->i_flags |= S_NOSEC;
+
+       return error;
+}
+EXPORT_SYMBOL(file_remove_suid);
+
 /**
  *     file_update_time        -       update mtime and ctime time
  *     @file: file accessed

diff --git a/mm/filemap.c b/mm/filemap.c
index 79c4b2b0b14eec1d05c93e3493dd02e0fd182829..21e5abfbcdf661ac3fbb4434d1058a8bec82baec 100644 (file)
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -1938,71 +1938,6 @@ struct page *read_cache_page(struct address_space *mapping,
 }
 EXPORT_SYMBOL(read_cache_page);
 
-/*
- * The logic we want is
- *
- *     if suid or (sgid and xgrp)
- *             remove privs
- */
-int should_remove_suid(struct dentry *dentry)
-{
-       umode_t mode = dentry->d_inode->i_mode;
-       int kill = 0;
-
-       /* suid always must be killed */
-       if (unlikely(mode & S_ISUID))
-               kill = ATTR_KILL_SUID;
-
-       /*
-        * sgid without any exec bits is just a mandatory locking mark; leave
-        * it alone.  If some exec bits are set, it's a real sgid; kill it.
-        */
-       if (unlikely((mode & S_ISGID) && (mode & S_IXGRP)))
-               kill |= ATTR_KILL_SGID;
-
-       if (unlikely(kill && !capable(CAP_FSETID) && S_ISREG(mode)))
-               return kill;
-
-       return 0;
-}
-EXPORT_SYMBOL(should_remove_suid);
-
-static int __remove_suid(struct dentry *dentry, int kill)
-{
-       struct iattr newattrs;
-
-       newattrs.ia_valid = ATTR_FORCE | kill;
-       return notify_change(dentry, &newattrs);
-}
-
-int file_remove_suid(struct file *file)
-{
-       struct dentry *dentry = file->f_path.dentry;
-       struct inode *inode = dentry->d_inode;
-       int killsuid;
-       int killpriv;
-       int error = 0;
-
-       /* Fast path for nothing security related */
-       if (IS_NOSEC(inode))
-               return 0;
-
-       killsuid = should_remove_suid(dentry);
-       killpriv = security_inode_need_killpriv(dentry);
-
-       if (killpriv < 0)
-               return killpriv;
-       if (killpriv)
-               error = security_inode_killpriv(dentry);
-       if (!error && killsuid)
-               error = __remove_suid(dentry, killsuid);
-       if (!error && (inode->i_sb->s_flags & MS_NOSEC))
-               inode->i_flags |= S_NOSEC;
-
-       return error;
-}
-EXPORT_SYMBOL(file_remove_suid);
-
 static size_t __iovec_copy_from_user_inatomic(char *vaddr,
                        const struct iovec *iov, size_t base, size_t bytes)
 {