clk-bcm2835: Read max core clock from firmware

[mirror_ubuntu-zesty-kernel.git] / fs / proc / proc_sysctl.c

diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c
index d4e37acd48217dcb1090a1ee68bb4ec4cb7226e5..231d295a9df7876f9da587944631448799b6b848 100644 (file)
--- a/fs/proc/proc_sysctl.c
+++ b/fs/proc/proc_sysctl.c
@@ -755,11 +755,18 @@ static int proc_sys_permission(struct inode *inode, int mask)
 static int proc_sys_setattr(struct dentry *dentry, struct iattr *attr)
 {
        struct inode *inode = d_inode(dentry);
+       struct user_namespace *s_user_ns;
        int error;
 
        if (attr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID))
                return -EPERM;
 
+       /* Don't let anyone mess with weird proc files */
+       s_user_ns = inode->i_sb->s_user_ns;
+       if (!kuid_has_mapping(s_user_ns, inode->i_uid) ||
+           !kgid_has_mapping(s_user_ns, inode->i_gid))
+               return -EPERM;
+
        error = setattr_prepare(dentry, attr);
        if (error)
                return error;