xref: /linux/include/linux/moduleloader.h (revision e999db587312e5b798421d803495f41d1283d7d7)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_MODULELOADER_H
3 #define _LINUX_MODULELOADER_H
4 /* The stuff needed for archs to support modules. */
5 
6 #include <linux/module.h>
7 #include <linux/elf.h>
8 
9 /* These may be implemented by architectures that need to hook into the
10  * module loader code.  Architectures that don't need to do anything special
11  * can just rely on the 'weak' default hooks defined in kernel/module.c.
12  * Note, however, that at least one of apply_relocate or apply_relocate_add
13  * must be implemented by each architecture.
14  */
15 
16 /* Adjust arch-specific sections.  Return 0 on success.  */
17 int module_frob_arch_sections(Elf_Ehdr *hdr,
18 			      Elf_Shdr *sechdrs,
19 			      char *secstrings,
20 			      struct module *mod);
21 
22 /* Additional bytes needed by arch in front of individual sections */
23 unsigned int arch_mod_section_prepend(struct module *mod, unsigned int section);
24 
25 /* Allocator used for allocating struct module, core sections and init
26    sections.  Returns NULL on failure. */
27 void *module_alloc(unsigned long size);
28 
29 /* Free memory returned from module_alloc. */
30 void module_memfree(void *module_region);
31 
32 /* Determines if the section name is an init section (that is only used during
33  * module loading).
34  */
35 bool module_init_section(const char *name);
36 
37 /* Determines if the section name is an exit section (that is only used during
38  * module unloading)
39  */
40 bool module_exit_section(const char *name);
41 
42 /*
43  * Apply the given relocation to the (simplified) ELF.  Return -error
44  * or 0.
45  */
46 #ifdef CONFIG_MODULES_USE_ELF_REL
47 int apply_relocate(Elf_Shdr *sechdrs,
48 		   const char *strtab,
49 		   unsigned int symindex,
50 		   unsigned int relsec,
51 		   struct module *mod);
52 #else
53 static inline int apply_relocate(Elf_Shdr *sechdrs,
54 				 const char *strtab,
55 				 unsigned int symindex,
56 				 unsigned int relsec,
57 				 struct module *me)
58 {
59 	printk(KERN_ERR "module %s: REL relocation unsupported\n",
60 	       module_name(me));
61 	return -ENOEXEC;
62 }
63 #endif
64 
65 /*
66  * Apply the given add relocation to the (simplified) ELF.  Return
67  * -error or 0
68  */
69 #ifdef CONFIG_MODULES_USE_ELF_RELA
70 int apply_relocate_add(Elf_Shdr *sechdrs,
71 		       const char *strtab,
72 		       unsigned int symindex,
73 		       unsigned int relsec,
74 		       struct module *mod);
75 #else
76 static inline int apply_relocate_add(Elf_Shdr *sechdrs,
77 				     const char *strtab,
78 				     unsigned int symindex,
79 				     unsigned int relsec,
80 				     struct module *me)
81 {
82 	printk(KERN_ERR "module %s: REL relocation unsupported\n",
83 	       module_name(me));
84 	return -ENOEXEC;
85 }
86 #endif
87 
88 /* Any final processing of module before access.  Return -error or 0. */
89 int module_finalize(const Elf_Ehdr *hdr,
90 		    const Elf_Shdr *sechdrs,
91 		    struct module *mod);
92 
93 /* Any cleanup needed when module leaves. */
94 void module_arch_cleanup(struct module *mod);
95 
96 /* Any cleanup before freeing mod->module_init */
97 void module_arch_freeing_init(struct module *mod);
98 
99 #if (defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)) && \
100 		!defined(CONFIG_KASAN_VMALLOC)
101 #include <linux/kasan.h>
102 #define MODULE_ALIGN (PAGE_SIZE << KASAN_SHADOW_SCALE_SHIFT)
103 #else
104 #define MODULE_ALIGN PAGE_SIZE
105 #endif
106 
107 #endif
108