LXR linux/include/linux/binfmts.h

   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;
  11
  12#define CORENAME_MAX_SIZE 128
  13
  14/*
  15 * This structure is used to hold the arguments that are used when loading binaries.
  16 */
  17struct linux_binprm {
  18#ifdef CONFIG_MMU
  19        struct vm_area_struct *vma;
  20        unsigned long vma_pages;
  21#else
  22# define MAX_ARG_PAGES  32
  23        struct page *page[MAX_ARG_PAGES];
  24#endif
  25        struct mm_struct *mm;
  26        unsigned long p; /* current top of mem */
  27        unsigned long argmin; /* rlimit marker for copy_strings() */
  28        unsigned int
  29                /* Should an execfd be passed to userspace? */
  30                have_execfd:1,
  31
  32                /* Use the creds of a script (see binfmt_misc) */
  33                execfd_creds:1,
  34                /*
  35                 * Set by bprm_creds_for_exec hook to indicate a
  36                 * privilege-gaining exec has happened. Used to set
  37                 * AT_SECURE auxv for glibc.
  38                 */
  39                secureexec:1,
  40                /*
  41                 * Set when errors can no longer be returned to the
  42                 * original userspace.
  43                 */
  44                point_of_no_return:1;
  45#ifdef __alpha__
  46        unsigned int taso:1;
  47#endif
  48        struct file *executable; /* Executable to pass to the interpreter */
  49        struct file *interpreter;
  50        struct file *file;
  51        struct cred *cred;      /* new credentials */
  52        int unsafe;             /* how unsafe this exec is (mask of LSM_UNSAFE_*) */
  53        unsigned int per_clear; /* bits to clear in current->personality */
  54        int argc, envc;
  55        const char *filename;   /* Name of binary as seen by procps */
  56        const char *interp;     /* Name of the binary really executed. Most
  57                                   of the time same as filename, but could be
  58                                   different for binfmt_{misc,script} */
  59        const char *fdpath;     /* generated filename for execveat */
  60        unsigned interp_flags;
  61        int execfd;             /* File descriptor of the executable */
  62        unsigned long loader, exec;
  63
  64        struct rlimit rlim_stack; /* Saved RLIMIT_STACK used during exec. */
  65
  66        char buf[BINPRM_BUF_SIZE];
  67} __randomize_layout;
  68
  69#define BINPRM_FLAGS_ENFORCE_NONDUMP_BIT 0
  70#define BINPRM_FLAGS_ENFORCE_NONDUMP (1 << BINPRM_FLAGS_ENFORCE_NONDUMP_BIT)
  71
  72/* filename of the binary will be inaccessible after exec */
  73#define BINPRM_FLAGS_PATH_INACCESSIBLE_BIT 2
  74#define BINPRM_FLAGS_PATH_INACCESSIBLE (1 << BINPRM_FLAGS_PATH_INACCESSIBLE_BIT)
  75
  76/* Function parameter for binfmt->coredump */
  77struct coredump_params {
  78        const kernel_siginfo_t *siginfo;
  79        struct pt_regs *regs;
  80        struct file *file;
  81        unsigned long limit;
  82        unsigned long mm_flags;
  83        loff_t written;
  84        loff_t pos;
  85};
  86
  87/*
  88 * This structure defines the functions that are used to load the binary formats that
  89 * linux accepts.
  90 */
  91struct linux_binfmt {
  92        struct list_head lh;
  93        struct module *module;
  94        int (*load_binary)(struct linux_binprm *);
  95        int (*load_shlib)(struct file *);
  96        int (*core_dump)(struct coredump_params *cprm);
  97        unsigned long min_coredump;     /* minimal dump size */
  98} __randomize_layout;
  99
 100extern void __register_binfmt(struct linux_binfmt *fmt, int insert);
 101
 102/* Registration of default binfmt handlers */
 103static inline void register_binfmt(struct linux_binfmt *fmt)
 104{
 105        __register_binfmt(fmt, 0);
 106}
 107/* Same as above, but adds a new binfmt at the top of the list */
 108static inline void insert_binfmt(struct linux_binfmt *fmt)
 109{
 110        __register_binfmt(fmt, 1);
 111}
 112
 113extern void unregister_binfmt(struct linux_binfmt *);
 114
 115extern int __must_check remove_arg_zero(struct linux_binprm *);
 116extern int begin_new_exec(struct linux_binprm * bprm);
 117extern void setup_new_exec(struct linux_binprm * bprm);
 118extern void finalize_exec(struct linux_binprm *bprm);
 119extern void would_dump(struct linux_binprm *, struct file *);
 120
 121extern int suid_dumpable;
 122
 123/* Stack area protections */
 124#define EXSTACK_DEFAULT   0     /* Whatever the arch defaults to */
 125#define EXSTACK_DISABLE_X 1     /* Disable executable stacks */
 126#define EXSTACK_ENABLE_X  2     /* Enable executable stacks */
 127
 128extern int setup_arg_pages(struct linux_binprm * bprm,
 129                           unsigned long stack_top,
 130                           int executable_stack);
 131extern int transfer_args_to_stack(struct linux_binprm *bprm,
 132                                  unsigned long *sp_location);
 133extern int bprm_change_interp(const char *interp, struct linux_binprm *bprm);
 134int copy_string_kernel(const char *arg, struct linux_binprm *bprm);
 135extern void set_binfmt(struct linux_binfmt *new);
 136extern ssize_t read_code(struct file *, unsigned long, loff_t, size_t);
 137
 138int kernel_execve(const char *filename,
 139                  const char *const *argv, const char *const *envp);
 140
 141#endif /* _LINUX_BINFMTS_H */
 142