xref: /linux-6.15/include/linux/binfmts.h (revision 17c324fa)
1 #ifndef _LINUX_BINFMTS_H
2 #define _LINUX_BINFMTS_H
3 
4 #include <linux/capability.h>
5 
6 struct pt_regs;
7 
8 /*
9  * These are the maximum length and maximum number of strings passed to the
10  * execve() system call.  MAX_ARG_STRLEN is essentially random but serves to
11  * prevent the kernel from being unduly impacted by misaddressed pointers.
12  * MAX_ARG_STRINGS is chosen to fit in a signed 32-bit integer.
13  */
14 #define MAX_ARG_STRLEN (PAGE_SIZE * 32)
15 #define MAX_ARG_STRINGS 0x7FFFFFFF
16 
17 /* sizeof(linux_binprm->buf) */
18 #define BINPRM_BUF_SIZE 128
19 
20 #ifdef __KERNEL__
21 
22 #define CORENAME_MAX_SIZE 128
23 
24 /*
25  * This structure is used to hold the arguments that are used when loading binaries.
26  */
27 struct linux_binprm{
28 	char buf[BINPRM_BUF_SIZE];
29 #ifdef CONFIG_MMU
30 	struct vm_area_struct *vma;
31 #else
32 # define MAX_ARG_PAGES	32
33 	struct page *page[MAX_ARG_PAGES];
34 #endif
35 	struct mm_struct *mm;
36 	unsigned long p; /* current top of mem */
37 	unsigned int sh_bang:1,
38 		     misc_bang:1;
39 #ifdef __alpha__
40 	unsigned int taso:1;
41 #endif
42 	unsigned int recursion_depth;
43 	struct file * file;
44 	int e_uid, e_gid;
45 	kernel_cap_t cap_post_exec_permitted;
46 	bool cap_effective;
47 	void *security;
48 	int argc, envc;
49 	char * filename;	/* Name of binary as seen by procps */
50 	char * interp;		/* Name of the binary really executed. Most
51 				   of the time same as filename, but could be
52 				   different for binfmt_{misc,script} */
53 	unsigned interp_flags;
54 	unsigned interp_data;
55 	unsigned long loader, exec;
56 };
57 
58 #define BINPRM_FLAGS_ENFORCE_NONDUMP_BIT 0
59 #define BINPRM_FLAGS_ENFORCE_NONDUMP (1 << BINPRM_FLAGS_ENFORCE_NONDUMP_BIT)
60 
61 /* fd of the binary should be passed to the interpreter */
62 #define BINPRM_FLAGS_EXECFD_BIT 1
63 #define BINPRM_FLAGS_EXECFD (1 << BINPRM_FLAGS_EXECFD_BIT)
64 
65 #define BINPRM_MAX_RECURSION 4
66 
67 /*
68  * This structure defines the functions that are used to load the binary formats that
69  * linux accepts.
70  */
71 struct linux_binfmt {
72 	struct list_head lh;
73 	struct module *module;
74 	int (*load_binary)(struct linux_binprm *, struct  pt_regs * regs);
75 	int (*load_shlib)(struct file *);
76 	int (*core_dump)(long signr, struct pt_regs *regs, struct file *file, unsigned long limit);
77 	unsigned long min_coredump;	/* minimal dump size */
78 	int hasvdso;
79 };
80 
81 extern int register_binfmt(struct linux_binfmt *);
82 extern void unregister_binfmt(struct linux_binfmt *);
83 
84 extern int prepare_binprm(struct linux_binprm *);
85 extern int __must_check remove_arg_zero(struct linux_binprm *);
86 extern int search_binary_handler(struct linux_binprm *,struct pt_regs *);
87 extern int flush_old_exec(struct linux_binprm * bprm);
88 
89 extern int suid_dumpable;
90 #define SUID_DUMP_DISABLE	0	/* No setuid dumping */
91 #define SUID_DUMP_USER		1	/* Dump as user of process */
92 #define SUID_DUMP_ROOT		2	/* Dump as root */
93 
94 /* Stack area protections */
95 #define EXSTACK_DEFAULT   0	/* Whatever the arch defaults to */
96 #define EXSTACK_DISABLE_X 1	/* Disable executable stacks */
97 #define EXSTACK_ENABLE_X  2	/* Enable executable stacks */
98 
99 extern int setup_arg_pages(struct linux_binprm * bprm,
100 			   unsigned long stack_top,
101 			   int executable_stack);
102 extern int bprm_mm_init(struct linux_binprm *bprm);
103 extern int copy_strings_kernel(int argc,char ** argv,struct linux_binprm *bprm);
104 extern void compute_creds(struct linux_binprm *binprm);
105 extern int do_coredump(long signr, int exit_code, struct pt_regs * regs);
106 extern int set_binfmt(struct linux_binfmt *new);
107 extern void free_bprm(struct linux_binprm *);
108 
109 #endif /* __KERNEL__ */
110 #endif /* _LINUX_BINFMTS_H */
111