xref: /linux/include/linux/moduleloader.h (revision 71e2f4dd5a65bd8dbca0b77661e75eea471168f8)
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 exit section (that is only used during
33  * module unloading)
34  */
35 bool module_exit_section(const char *name);
36 
37 /*
38  * Apply the given relocation to the (simplified) ELF.  Return -error
39  * or 0.
40  */
41 #ifdef CONFIG_MODULES_USE_ELF_REL
42 int apply_relocate(Elf_Shdr *sechdrs,
43 		   const char *strtab,
44 		   unsigned int symindex,
45 		   unsigned int relsec,
46 		   struct module *mod);
47 #else
48 static inline int apply_relocate(Elf_Shdr *sechdrs,
49 				 const char *strtab,
50 				 unsigned int symindex,
51 				 unsigned int relsec,
52 				 struct module *me)
53 {
54 	printk(KERN_ERR "module %s: REL relocation unsupported\n",
55 	       module_name(me));
56 	return -ENOEXEC;
57 }
58 #endif
59 
60 /*
61  * Apply the given add relocation to the (simplified) ELF.  Return
62  * -error or 0
63  */
64 #ifdef CONFIG_MODULES_USE_ELF_RELA
65 int apply_relocate_add(Elf_Shdr *sechdrs,
66 		       const char *strtab,
67 		       unsigned int symindex,
68 		       unsigned int relsec,
69 		       struct module *mod);
70 #else
71 static inline int apply_relocate_add(Elf_Shdr *sechdrs,
72 				     const char *strtab,
73 				     unsigned int symindex,
74 				     unsigned int relsec,
75 				     struct module *me)
76 {
77 	printk(KERN_ERR "module %s: REL relocation unsupported\n",
78 	       module_name(me));
79 	return -ENOEXEC;
80 }
81 #endif
82 
83 /* Any final processing of module before access.  Return -error or 0. */
84 int module_finalize(const Elf_Ehdr *hdr,
85 		    const Elf_Shdr *sechdrs,
86 		    struct module *mod);
87 
88 /* Any cleanup needed when module leaves. */
89 void module_arch_cleanup(struct module *mod);
90 
91 /* Any cleanup before freeing mod->module_init */
92 void module_arch_freeing_init(struct module *mod);
93 
94 #ifdef CONFIG_KASAN
95 #include <linux/kasan.h>
96 #define MODULE_ALIGN (PAGE_SIZE << KASAN_SHADOW_SCALE_SHIFT)
97 #else
98 #define MODULE_ALIGN PAGE_SIZE
99 #endif
100 
101 #endif
102