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 12 #define CORENAME_MAX_SIZE 128 13 14 /* 15 * This structure is used to hold the arguments that are used when loading binaries. 16 */ 17 struct 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 /* 30 * True after the bprm_set_creds hook has been called once 31 * (multiple calls can be made via prepare_binprm() for 32 * binfmt_script/misc). 33 */ 34 called_set_creds:1, 35 /* 36 * True if most recent call to the commoncaps bprm_set_creds 37 * hook (due to multiple prepare_binprm() calls from the 38 * binfmt_script/misc handlers) resulted in elevated 39 * privileges. 40 */ 41 cap_elevated:1, 42 /* 43 * Set by bprm_set_creds hook to indicate a privilege-gaining 44 * exec has happened. Used to sanitize execution environment 45 * and to set AT_SECURE auxv for glibc. 46 */ 47 secureexec:1, 48 /* 49 * Set by flush_old_exec, when exec_mmap has been called. 50 * This is past the point of no return, when the 51 * exec_update_mutex has been taken. 52 */ 53 called_exec_mmap:1; 54 #ifdef __alpha__ 55 unsigned int taso:1; 56 #endif 57 unsigned int recursion_depth; /* only for search_binary_handler() */ 58 struct file * file; 59 struct cred *cred; /* new credentials */ 60 int unsafe; /* how unsafe this exec is (mask of LSM_UNSAFE_*) */ 61 unsigned int per_clear; /* bits to clear in current->personality */ 62 int argc, envc; 63 const char * filename; /* Name of binary as seen by procps */ 64 const char * interp; /* Name of the binary really executed. Most 65 of the time same as filename, but could be 66 different for binfmt_{misc,script} */ 67 unsigned interp_flags; 68 unsigned interp_data; 69 unsigned long loader, exec; 70 71 struct rlimit rlim_stack; /* Saved RLIMIT_STACK used during exec. */ 72 73 char buf[BINPRM_BUF_SIZE]; 74 } __randomize_layout; 75 76 #define BINPRM_FLAGS_ENFORCE_NONDUMP_BIT 0 77 #define BINPRM_FLAGS_ENFORCE_NONDUMP (1 << BINPRM_FLAGS_ENFORCE_NONDUMP_BIT) 78 79 /* fd of the binary should be passed to the interpreter */ 80 #define BINPRM_FLAGS_EXECFD_BIT 1 81 #define BINPRM_FLAGS_EXECFD (1 << BINPRM_FLAGS_EXECFD_BIT) 82 83 /* filename of the binary will be inaccessible after exec */ 84 #define BINPRM_FLAGS_PATH_INACCESSIBLE_BIT 2 85 #define BINPRM_FLAGS_PATH_INACCESSIBLE (1 << BINPRM_FLAGS_PATH_INACCESSIBLE_BIT) 86 87 /* Function parameter for binfmt->coredump */ 88 struct coredump_params { 89 const kernel_siginfo_t *siginfo; 90 struct pt_regs *regs; 91 struct file *file; 92 unsigned long limit; 93 unsigned long mm_flags; 94 loff_t written; 95 loff_t pos; 96 }; 97 98 /* 99 * This structure defines the functions that are used to load the binary formats that 100 * linux accepts. 101 */ 102 struct linux_binfmt { 103 struct list_head lh; 104 struct module *module; 105 int (*load_binary)(struct linux_binprm *); 106 int (*load_shlib)(struct file *); 107 int (*core_dump)(struct coredump_params *cprm); 108 unsigned long min_coredump; /* minimal dump size */ 109 } __randomize_layout; 110 111 extern void __register_binfmt(struct linux_binfmt *fmt, int insert); 112 113 /* Registration of default binfmt handlers */ 114 static inline void register_binfmt(struct linux_binfmt *fmt) 115 { 116 __register_binfmt(fmt, 0); 117 } 118 /* Same as above, but adds a new binfmt at the top of the list */ 119 static inline void insert_binfmt(struct linux_binfmt *fmt) 120 { 121 __register_binfmt(fmt, 1); 122 } 123 124 extern void unregister_binfmt(struct linux_binfmt *); 125 126 extern int prepare_binprm(struct linux_binprm *); 127 extern int __must_check remove_arg_zero(struct linux_binprm *); 128 extern int search_binary_handler(struct linux_binprm *); 129 extern int flush_old_exec(struct linux_binprm * bprm); 130 extern void setup_new_exec(struct linux_binprm * bprm); 131 extern void finalize_exec(struct linux_binprm *bprm); 132 extern void would_dump(struct linux_binprm *, struct file *); 133 134 extern int suid_dumpable; 135 136 /* Stack area protections */ 137 #define EXSTACK_DEFAULT 0 /* Whatever the arch defaults to */ 138 #define EXSTACK_DISABLE_X 1 /* Disable executable stacks */ 139 #define EXSTACK_ENABLE_X 2 /* Enable executable stacks */ 140 141 extern int setup_arg_pages(struct linux_binprm * bprm, 142 unsigned long stack_top, 143 int executable_stack); 144 extern int transfer_args_to_stack(struct linux_binprm *bprm, 145 unsigned long *sp_location); 146 extern int bprm_change_interp(const char *interp, struct linux_binprm *bprm); 147 extern int copy_strings_kernel(int argc, const char *const *argv, 148 struct linux_binprm *bprm); 149 extern void install_exec_creds(struct linux_binprm *bprm); 150 extern void set_binfmt(struct linux_binfmt *new); 151 extern ssize_t read_code(struct file *, unsigned long, loff_t, size_t); 152 153 extern int do_execve(struct filename *, 154 const char __user * const __user *, 155 const char __user * const __user *); 156 extern int do_execveat(int, struct filename *, 157 const char __user * const __user *, 158 const char __user * const __user *, 159 int); 160 int do_execve_file(struct file *file, void *__argv, void *__envp); 161 162 #endif /* _LINUX_BINFMTS_H */ 163