Re: [PATCH v10 2/9] proc: allow to mount many instances of proc in one pid namespace

Eric W. Biederman
2020-04-02T15:34:38Z

> diff --git a/include/linux/proc_fs.h b/include/linux/proc_fs.h
> index 40a7982b7285..5920a4ecd71b 100644
> --- a/include/linux/proc_fs.h
> +++ b/include/linux/proc_fs.h
> @@ -27,6 +27,17 @@ struct proc_ops {
> unsigned long (*proc_get_unmapped_area)(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
> };
>
> +struct proc_fs_info {
> + struct pid_namespace *pid_ns;
> + struct dentry *proc_self; /* For /proc/self */
> + struct dentry *proc_thread_self; /* For /proc/thread-self */
> +};

Minor nit.

I have not seen a patch where you remove proc_self and proc_thread_self
from struct pid_namepace.

Ideally it would have been in this patch. But as it won't break
anyone's bisection can you please have a follow up patch that removes
those fields?

Thank you,
Eric

> +
> +static inline struct proc_fs_info *proc_sb_info(struct super_block *sb)
> +{
> + return sb->s_fs_info;
> +}
> +
> #ifdef CONFIG_PROC_FS
>
> typedef int (*proc_write_t)(struct file *, char *, size_t);
> @@ -161,6 +172,7 @@ int open_related_ns(struct ns_common *ns,
> /* get the associated pid namespace for a file in procfs */
> static inline struct pid_namespace *proc_pid_ns(const struct inode *inode)
> {
> + return proc_sb_info(inode->i_sb)->pid_ns;
> return inode->i_sb->s_fs_info;
> }