fs: Fix S_NOSEC handling
file_remove_suid() could mistakenly set S_NOSEC inode bit when root was
modifying the file. As a result following writes to the file by ordinary
user would avoid clearing suid or sgid bits.
Fix the bug by checking actual mode bits before setting S_NOSEC.
CC: stable@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/inode.c b/fs/inode.c
index e8d6268..07f4cb5 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -1706,8 +1706,8 @@
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;
+ if (!error)
+ inode_has_no_xattr(inode);
return error;
}