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 10 struct filename; 11 struct 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 */ 18 struct 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 struct file *executable; /* Executable to pass to the interpreter */ 47 struct file *interpreter; 48 struct file *file; 49 struct cred *cred; /* new credentials */ 50 int unsafe; /* how unsafe this exec is (mask of LSM_UNSAFE_*) */ 51 unsigned int per_clear; /* bits to clear in current->personality */ 52 int argc, envc; 53 const char *filename; /* Name of binary as seen by procps */ 54 const char *interp; /* Name of the binary really executed. Most 55 of the time same as filename, but could be 56 different for binfmt_{misc,script} */ 57 const char *fdpath; /* generated filename for execveat */ 58 unsigned interp_flags; 59 int execfd; /* File descriptor of the executable */ 60 unsigned long loader, exec; 61 62 struct rlimit rlim_stack; /* Saved RLIMIT_STACK used during exec. */ 63 64 char buf[BINPRM_BUF_SIZE]; 65 } __randomize_layout; 66 67 #define BINPRM_FLAGS_ENFORCE_NONDUMP_BIT 0 68 #define BINPRM_FLAGS_ENFORCE_NONDUMP (1 << BINPRM_FLAGS_ENFORCE_NONDUMP_BIT) 69 70 /* filename of the binary will be inaccessible after exec */ 71 #define BINPRM_FLAGS_PATH_INACCESSIBLE_BIT 2 72 #define BINPRM_FLAGS_PATH_INACCESSIBLE (1 << BINPRM_FLAGS_PATH_INACCESSIBLE_BIT) 73 74 /* preserve argv0 for the interpreter */ 75 #define BINPRM_FLAGS_PRESERVE_ARGV0_BIT 3 76 #define BINPRM_FLAGS_PRESERVE_ARGV0 (1 << BINPRM_FLAGS_PRESERVE_ARGV0_BIT) 77 78 /* 79 * This structure defines the functions that are used to load the binary formats that 80 * linux accepts. 81 */ 82 struct linux_binfmt { 83 struct list_head lh; 84 struct module *module; 85 int (*load_binary)(struct linux_binprm *); 86 int (*load_shlib)(struct file *); 87 #ifdef CONFIG_COREDUMP 88 int (*core_dump)(struct coredump_params *cprm); 89 unsigned long min_coredump; /* minimal dump size */ 90 #endif 91 } __randomize_layout; 92 93 extern void __register_binfmt(struct linux_binfmt *fmt, int insert); 94 95 /* Registration of default binfmt handlers */ register_binfmt(struct linux_binfmt * fmt)96 static inline void register_binfmt(struct linux_binfmt *fmt) 97 { 98 __register_binfmt(fmt, 0); 99 } 100 /* Same as above, but adds a new binfmt at the top of the list */ insert_binfmt(struct linux_binfmt * fmt)101 static inline void insert_binfmt(struct linux_binfmt *fmt) 102 { 103 __register_binfmt(fmt, 1); 104 } 105 106 extern void unregister_binfmt(struct linux_binfmt *); 107 108 extern int __must_check remove_arg_zero(struct linux_binprm *); 109 extern int begin_new_exec(struct linux_binprm * bprm); 110 extern void setup_new_exec(struct linux_binprm * bprm); 111 extern void finalize_exec(struct linux_binprm *bprm); 112 extern void would_dump(struct linux_binprm *, struct file *); 113 114 extern int suid_dumpable; 115 116 /* Stack area protections */ 117 #define EXSTACK_DEFAULT 0 /* Whatever the arch defaults to */ 118 #define EXSTACK_DISABLE_X 1 /* Disable executable stacks */ 119 #define EXSTACK_ENABLE_X 2 /* Enable executable stacks */ 120 121 extern int setup_arg_pages(struct linux_binprm * bprm, 122 unsigned long stack_top, 123 int executable_stack); 124 extern int transfer_args_to_stack(struct linux_binprm *bprm, 125 unsigned long *sp_location); 126 extern int bprm_change_interp(const char *interp, struct linux_binprm *bprm); 127 int copy_string_kernel(const char *arg, struct linux_binprm *bprm); 128 extern void set_binfmt(struct linux_binfmt *new); 129 extern ssize_t read_code(struct file *, unsigned long, loff_t, size_t); 130 131 int kernel_execve(const char *filename, 132 const char *const *argv, const char *const *envp); 133 134 #endif /* _LINUX_BINFMTS_H */ 135
