linux/fs/proc/fd.c

// SPDX-License-Identifier: GPL-2.0
#include <linux/sched/signal.h>
#include <linux/errno.h>
#include <linux/dcache.h>
#include <linux/path.h>
#include <linux/fdtable.h>
#include <linux/namei.h>
#include <linux/pid.h>
#include <linux/ptrace.h>
#include <linux/bitmap.h>
#include <linux/security.h>
#include <linux/file.h>
#include <linux/seq_file.h>
#include <linux/fs.h>
#include <linux/filelock.h>

#include <linux/proc_fs.h>

#include "../mount.h"
#include "internal.h"
#include "fd.h"

static int seq_show(struct seq_file *m, void *v)
{ … }

static int seq_fdinfo_open(struct inode *inode, struct file *file)
{ … }

/**
 * Shared /proc/pid/fdinfo and /proc/pid/fdinfo/fd permission helper to ensure
 * that the current task has PTRACE_MODE_READ in addition to the normal
 * POSIX-like checks.
 */
static int proc_fdinfo_permission(struct mnt_idmap *idmap, struct inode *inode,
				  int mask)
{ … }

static const struct inode_operations proc_fdinfo_file_inode_operations = …;

static const struct file_operations proc_fdinfo_file_operations = …;

static bool tid_fd_mode(struct task_struct *task, unsigned fd, fmode_t *mode)
{ … }

static void tid_fd_update_inode(struct task_struct *task, struct inode *inode,
				fmode_t f_mode)
{ … }

static int tid_fd_revalidate(struct dentry *dentry, unsigned int flags)
{ … }

static const struct dentry_operations tid_fd_dentry_operations = …;

static int proc_fd_link(struct dentry *dentry, struct path *path)
{ … }

struct fd_data { … };

static struct dentry *proc_fd_instantiate(struct dentry *dentry,
	struct task_struct *task, const void *ptr)
{ … }

static struct dentry *proc_lookupfd_common(struct inode *dir,
					   struct dentry *dentry,
					   instantiate_t instantiate)
{ … }

static int proc_readfd_common(struct file *file, struct dir_context *ctx,
			      instantiate_t instantiate)
{ … }

static int proc_readfd_count(struct inode *inode, loff_t *count)
{ … }

static int proc_readfd(struct file *file, struct dir_context *ctx)
{ … }

const struct file_operations proc_fd_operations = …;

static struct dentry *proc_lookupfd(struct inode *dir, struct dentry *dentry,
				    unsigned int flags)
{ … }

/*
 * /proc/pid/fd needs a special permission handler so that a process can still
 * access /proc/self/fd after it has executed a setuid().
 */
int proc_fd_permission(struct mnt_idmap *idmap,
		       struct inode *inode, int mask)
{ … }

static int proc_fd_getattr(struct mnt_idmap *idmap,
			const struct path *path, struct kstat *stat,
			u32 request_mask, unsigned int query_flags)
{ … }

const struct inode_operations proc_fd_inode_operations = …;

static struct dentry *proc_fdinfo_instantiate(struct dentry *dentry,
	struct task_struct *task, const void *ptr)
{ … }

static struct dentry *
proc_lookupfdinfo(struct inode *dir, struct dentry *dentry, unsigned int flags)
{ … }

static int proc_readfdinfo(struct file *file, struct dir_context *ctx)
{ … }

const struct inode_operations proc_fdinfo_inode_operations = …;

const struct file_operations proc_fdinfo_operations = …;