xref: /openbmc/linux/include/linux/binfmts.h (revision 6cb4f3b0)
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 		/* 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 	unsigned interp_flags;
60 	int execfd;		/* File descriptor of the executable */
61 	unsigned long loader, exec;
62 
63 	struct rlimit rlim_stack; /* Saved RLIMIT_STACK used during exec. */
64 
65 	char buf[BINPRM_BUF_SIZE];
66 } __randomize_layout;
67 
68 #define BINPRM_FLAGS_ENFORCE_NONDUMP_BIT 0
69 #define BINPRM_FLAGS_ENFORCE_NONDUMP (1 << BINPRM_FLAGS_ENFORCE_NONDUMP_BIT)
70 
71 /* filename of the binary will be inaccessible after exec */
72 #define BINPRM_FLAGS_PATH_INACCESSIBLE_BIT 2
73 #define BINPRM_FLAGS_PATH_INACCESSIBLE (1 << BINPRM_FLAGS_PATH_INACCESSIBLE_BIT)
74 
75 /* Function parameter for binfmt->coredump */
76 struct coredump_params {
77 	const kernel_siginfo_t *siginfo;
78 	struct pt_regs *regs;
79 	struct file *file;
80 	unsigned long limit;
81 	unsigned long mm_flags;
82 	loff_t written;
83 	loff_t pos;
84 };
85 
86 /*
87  * This structure defines the functions that are used to load the binary formats that
88  * linux accepts.
89  */
90 struct linux_binfmt {
91 	struct list_head lh;
92 	struct module *module;
93 	int (*load_binary)(struct linux_binprm *);
94 	int (*load_shlib)(struct file *);
95 	int (*core_dump)(struct coredump_params *cprm);
96 	unsigned long min_coredump;	/* minimal dump size */
97 } __randomize_layout;
98 
99 extern void __register_binfmt(struct linux_binfmt *fmt, int insert);
100 
101 /* Registration of default binfmt handlers */
102 static inline void register_binfmt(struct linux_binfmt *fmt)
103 {
104 	__register_binfmt(fmt, 0);
105 }
106 /* Same as above, but adds a new binfmt at the top of the list */
107 static inline void insert_binfmt(struct linux_binfmt *fmt)
108 {
109 	__register_binfmt(fmt, 1);
110 }
111 
112 extern void unregister_binfmt(struct linux_binfmt *);
113 
114 extern int __must_check remove_arg_zero(struct linux_binprm *);
115 extern int begin_new_exec(struct linux_binprm * bprm);
116 extern void setup_new_exec(struct linux_binprm * bprm);
117 extern void finalize_exec(struct linux_binprm *bprm);
118 extern void would_dump(struct linux_binprm *, struct file *);
119 
120 extern int suid_dumpable;
121 
122 /* Stack area protections */
123 #define EXSTACK_DEFAULT   0	/* Whatever the arch defaults to */
124 #define EXSTACK_DISABLE_X 1	/* Disable executable stacks */
125 #define EXSTACK_ENABLE_X  2	/* Enable executable stacks */
126 
127 extern int setup_arg_pages(struct linux_binprm * bprm,
128 			   unsigned long stack_top,
129 			   int executable_stack);
130 extern int transfer_args_to_stack(struct linux_binprm *bprm,
131 				  unsigned long *sp_location);
132 extern int bprm_change_interp(const char *interp, struct linux_binprm *bprm);
133 int copy_string_kernel(const char *arg, struct linux_binprm *bprm);
134 extern void set_binfmt(struct linux_binfmt *new);
135 extern ssize_t read_code(struct file *, unsigned long, loff_t, size_t);
136 
137 extern int do_execve(struct filename *,
138 		     const char __user * const __user *,
139 		     const char __user * const __user *);
140 extern int do_execveat(int, struct filename *,
141 		       const char __user * const __user *,
142 		       const char __user * const __user *,
143 		       int);
144 int do_execve_file(struct file *file, void *__argv, void *__envp);
145 
146 #endif /* _LINUX_BINFMTS_H */
147