xref: /linux/include/linux/moduleloader.h (revision 07f0148aafe8c95a3a76cd59e9e75b4d78d1d31d)
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 /* arch may override to do additional checking of ELF header architecture */
17 bool module_elf_check_arch(Elf_Ehdr *hdr);
18 
19 /* Adjust arch-specific sections.  Return 0 on success.  */
20 int module_frob_arch_sections(Elf_Ehdr *hdr,
21 			      Elf_Shdr *sechdrs,
22 			      char *secstrings,
23 			      struct module *mod);
24 
25 /* Additional bytes needed by arch in front of individual sections */
26 unsigned int arch_mod_section_prepend(struct module *mod, unsigned int section);
27 
28 /* Allocator used for allocating struct module, core sections and init
29    sections.  Returns NULL on failure. */
30 void *module_alloc(unsigned long size);
31 
32 /* Free memory returned from module_alloc. */
33 void module_memfree(void *module_region);
34 
35 /* Determines if the section name is an init section (that is only used during
36  * module loading).
37  */
38 bool module_init_section(const char *name);
39 
40 /* Determines if the section name is an exit section (that is only used during
41  * module unloading)
42  */
43 bool module_exit_section(const char *name);
44 
45 /*
46  * Apply the given relocation to the (simplified) ELF.  Return -error
47  * or 0.
48  */
49 #ifdef CONFIG_MODULES_USE_ELF_REL
50 int apply_relocate(Elf_Shdr *sechdrs,
51 		   const char *strtab,
52 		   unsigned int symindex,
53 		   unsigned int relsec,
54 		   struct module *mod);
55 #else
56 static inline int apply_relocate(Elf_Shdr *sechdrs,
57 				 const char *strtab,
58 				 unsigned int symindex,
59 				 unsigned int relsec,
60 				 struct module *me)
61 {
62 	printk(KERN_ERR "module %s: REL relocation unsupported\n",
63 	       module_name(me));
64 	return -ENOEXEC;
65 }
66 #endif
67 
68 /*
69  * Apply the given add relocation to the (simplified) ELF.  Return
70  * -error or 0
71  */
72 #ifdef CONFIG_MODULES_USE_ELF_RELA
73 int apply_relocate_add(Elf_Shdr *sechdrs,
74 		       const char *strtab,
75 		       unsigned int symindex,
76 		       unsigned int relsec,
77 		       struct module *mod);
78 #else
79 static inline int apply_relocate_add(Elf_Shdr *sechdrs,
80 				     const char *strtab,
81 				     unsigned int symindex,
82 				     unsigned int relsec,
83 				     struct module *me)
84 {
85 	printk(KERN_ERR "module %s: REL relocation unsupported\n",
86 	       module_name(me));
87 	return -ENOEXEC;
88 }
89 #endif
90 
91 /* Any final processing of module before access.  Return -error or 0. */
92 int module_finalize(const Elf_Ehdr *hdr,
93 		    const Elf_Shdr *sechdrs,
94 		    struct module *mod);
95 
96 /* Any cleanup needed when module leaves. */
97 void module_arch_cleanup(struct module *mod);
98 
99 /* Any cleanup before freeing mod->module_init */
100 void module_arch_freeing_init(struct module *mod);
101 
102 #if (defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)) && \
103 		!defined(CONFIG_KASAN_VMALLOC)
104 #include <linux/kasan.h>
105 #define MODULE_ALIGN (PAGE_SIZE << KASAN_SHADOW_SCALE_SHIFT)
106 #else
107 #define MODULE_ALIGN PAGE_SIZE
108 #endif
109 
110 #endif
111