1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _LINUX_BINFMTS_H
3#define _LINUX_BINFMTS_H
4
5#include <linux/sched.h>
6#include <linux/unistd.h>
7#include <asm/exec.h>
8#include <uapi/linux/binfmts.h>
9
10struct filename;
11struct coredump_params;
12
13#define CORENAME_MAX_SIZE 128
14
15/*
16 * This structure is used to hold the arguments that are used when loading binaries.
17 */
18struct linux_binprm {
19#ifdef CONFIG_MMU
20 struct vm_area_struct *vma;
21 unsigned long vma_pages;
22#else
23# define MAX_ARG_PAGES 32
24 struct page *page[MAX_ARG_PAGES];
25#endif
26 struct mm_struct *mm;
27 unsigned long p; /* current top of mem */
28 unsigned long argmin; /* rlimit marker for copy_strings() */
29 unsigned int
30 /* Should an execfd be passed to userspace? */
31 have_execfd:1,
32
33 /* Use the creds of a script (see binfmt_misc) */
34 execfd_creds:1,
35 /*
36 * Set by bprm_creds_for_exec hook to indicate a
37 * privilege-gaining exec has happened. Used to set
38 * AT_SECURE auxv for glibc.
39 */
40 secureexec:1,
41 /*
42 * Set when errors can no longer be returned to the
43 * original userspace.
44 */
45 point_of_no_return:1;
46#ifdef __alpha__
47 unsigned int taso:1;
48#endif
49 struct file *executable; /* Executable to pass to the interpreter */
50 struct file *interpreter;
51 struct file *file;
52 struct cred *cred; /* new credentials */
53 int unsafe; /* how unsafe this exec is (mask of LSM_UNSAFE_*) */
54 unsigned int per_clear; /* bits to clear in current->personality */
55 int argc, envc;
56 const char *filename; /* Name of binary as seen by procps */
57 const char *interp; /* Name of the binary really executed. Most
58 of the time same as filename, but could be
59 different for binfmt_{misc,script} */
60 const char *fdpath; /* generated filename for execveat */
61 unsigned interp_flags;
62 int execfd; /* File descriptor of the executable */
63 unsigned long loader, exec;
64
65 struct rlimit rlim_stack; /* Saved RLIMIT_STACK used during exec. */
66
67 char buf[BINPRM_BUF_SIZE];
68} __randomize_layout;
69
70#define BINPRM_FLAGS_ENFORCE_NONDUMP_BIT 0
71#define BINPRM_FLAGS_ENFORCE_NONDUMP (1 << BINPRM_FLAGS_ENFORCE_NONDUMP_BIT)
72
73/* filename of the binary will be inaccessible after exec */
74#define BINPRM_FLAGS_PATH_INACCESSIBLE_BIT 2
75#define BINPRM_FLAGS_PATH_INACCESSIBLE (1 << BINPRM_FLAGS_PATH_INACCESSIBLE_BIT)
76
77/* preserve argv0 for the interpreter */
78#define BINPRM_FLAGS_PRESERVE_ARGV0_BIT 3
79#define BINPRM_FLAGS_PRESERVE_ARGV0 (1 << BINPRM_FLAGS_PRESERVE_ARGV0_BIT)
80
81/*
82 * This structure defines the functions that are used to load the binary formats that
83 * linux accepts.
84 */
85struct linux_binfmt {
86 struct list_head lh;
87 struct module *module;
88 int (*load_binary)(struct linux_binprm *);
89 int (*load_shlib)(struct file *);
90#ifdef CONFIG_COREDUMP
91 int (*core_dump)(struct coredump_params *cprm);
92 unsigned long min_coredump; /* minimal dump size */
93#endif
94} __randomize_layout;
95
96extern void __register_binfmt(struct linux_binfmt *fmt, int insert);
97
98/* Registration of default binfmt handlers */
99static inline void register_binfmt(struct linux_binfmt *fmt)
100{
101 __register_binfmt(fmt, 0);
102}
103/* Same as above, but adds a new binfmt at the top of the list */
104static inline void insert_binfmt(struct linux_binfmt *fmt)
105{
106 __register_binfmt(fmt, 1);
107}
108
109extern void unregister_binfmt(struct linux_binfmt *);
110
111extern int __must_check remove_arg_zero(struct linux_binprm *);
112extern int begin_new_exec(struct linux_binprm * bprm);
113extern void setup_new_exec(struct linux_binprm * bprm);
114extern void finalize_exec(struct linux_binprm *bprm);
115extern void would_dump(struct linux_binprm *, struct file *);
116
117extern int suid_dumpable;
118
119/* Stack area protections */
120#define EXSTACK_DEFAULT 0 /* Whatever the arch defaults to */
121#define EXSTACK_DISABLE_X 1 /* Disable executable stacks */
122#define EXSTACK_ENABLE_X 2 /* Enable executable stacks */
123
124extern int setup_arg_pages(struct linux_binprm * bprm,
125 unsigned long stack_top,
126 int executable_stack);
127extern int transfer_args_to_stack(struct linux_binprm *bprm,
128 unsigned long *sp_location);
129extern int bprm_change_interp(const char *interp, struct linux_binprm *bprm);
130int copy_string_kernel(const char *arg, struct linux_binprm *bprm);
131extern void set_binfmt(struct linux_binfmt *new);
132extern ssize_t read_code(struct file *, unsigned long, loff_t, size_t);
133
134int kernel_execve(const char *filename,
135 const char *const *argv, const char *const *envp);
136
137#endif /* _LINUX_BINFMTS_H */
138

source code of linux/include/linux/binfmts.h