// SPDX-License-Identifier: GPL-2.0-only/* *  linux/arch/arm/kernel/module.c * *  Copyright (C) 2002 Russell King. *  Modified for nommu by Hyok S. Choi * * Module allocation method suggested by Andi Kleen. */#include <linux/module.h>#include <linux/moduleloader.h>#include <linux/kernel.h>#include <linux/mm.h>#include <linux/elf.h>#include <linux/vmalloc.h>#include <linux/fs.h>#include <linux/string.h>#include <linux/gfp.h> #include <asm/pgtable.h>#include <asm/sections.h>#include <asm/smp_plat.h>#include <asm/unwind.h>#include <asm/opcodes.h> #ifdef CONFIG_XIP_KERNEL/* * The XIP kernel text is mapped in the module area for modules and * some other stuff to work without any indirect relocations. * MODULES_VADDR is redefined here and not in asm/memory.h to avoid * recompiling the whole kernel when CONFIG_XIP_KERNEL is turned on/off. */#undef MODULES_VADDR#define MODULES_VADDR	(((unsigned long)_exiprom + ~PMD_MASK) & PMD_MASK)#endif #ifdef CONFIG_MMUvoid *module_alloc(unsigned long size){	gfp_t gfp_mask = GFP_KERNEL;	void *p; 	/* Silence the initial allocation */	if (IS_ENABLED(CONFIG_ARM_MODULE_PLTS))		gfp_mask |= __GFP_NOWARN; 	p = __vmalloc_node_range(size, 1, MODULES_VADDR, MODULES_END,				gfp_mask, PAGE_KERNEL_EXEC, 0, NUMA_NO_NODE,				__builtin_return_address(0));	if (!IS_ENABLED(CONFIG_ARM_MODULE_PLTS) || p)		return p;	return __vmalloc_node_range(size, 1,  VMALLOC_START, VMALLOC_END,				GFP_KERNEL, PAGE_KERNEL_EXEC, 0, NUMA_NO_NODE,				__builtin_return_address(0));}#endif bool module_exit_section(const char *name){	return strstarts(name, ".exit") ||		strstarts(name, ".ARM.extab.exit") ||		strstarts(name, ".ARM.exidx.exit");} intapply_relocate(Elf32_Shdr *sechdrs, const char *strtab, unsigned int symindex,	       unsigned int relindex, struct module *module){	Elf32_Shdr *symsec = sechdrs + symindex;	Elf32_Shdr *relsec = sechdrs + relindex;	Elf32_Shdr *dstsec = sechdrs + relsec->sh_info;	Elf32_Rel *rel = (void *)relsec->sh_addr;	unsigned int i; 	for (i = 0; i < relsec->sh_size / sizeof(Elf32_Rel); i++, rel++) {		unsigned long loc;		Elf32_Sym *sym;		const char *symname;		s32 offset;		u32 tmp;#ifdef CONFIG_THUMB2_KERNEL		u32 upper, lower, sign, j1, j2;#endif 		offset = ELF32_R_SYM(rel->r_info);		if (offset < 0 || offset > (symsec->sh_size / sizeof(Elf32_Sym))) {			pr_err("%s: section %u reloc %u: bad relocation sym offset\n",				module->name, relindex, i);			return -ENOEXEC;		} 		sym = ((Elf32_Sym *)symsec->sh_addr) + offset;		symname = strtab + sym->st_name; 		if (rel->r_offset < 0 || rel->r_offset > dstsec->sh_size - sizeof(u32)) {			pr_err("%s: section %u reloc %u sym '%s': out of bounds relocation, offset %d size %u\n",			       module->name, relindex, i, symname,			       rel->r_offset, dstsec->sh_size);			return -ENOEXEC;		} 		loc = dstsec->sh_addr + rel->r_offset; 		switch (ELF32_R_TYPE(rel->r_info)) {		case R_ARM_NONE:			/* ignore */			break; 		case R_ARM_ABS32:		case R_ARM_TARGET1:			*(u32 *)loc += sym->st_value;			break; 		case R_ARM_PC24:		case R_ARM_CALL:		case R_ARM_JUMP24:			if (sym->st_value & 3) {				pr_err("%s: section %u reloc %u sym '%s': unsupported interworking call (ARM -> Thumb)\n",				       module->name, relindex, i, symname);				return -ENOEXEC;			} 			offset = __mem_to_opcode_arm(*(u32 *)loc);			offset = (offset & 0x00ffffff) << 2;			if (offset & 0x02000000)				offset -= 0x04000000; 			offset += sym->st_value - loc; 			/*			 * Route through a PLT entry if 'offset' exceeds the			 * supported range. Note that 'offset + loc + 8'			 * contains the absolute jump target, i.e.,			 * @sym + addend, corrected for the +8 PC bias.			 */			if (IS_ENABLED(CONFIG_ARM_MODULE_PLTS) &&			    (offset <= (s32)0xfe000000 ||			     offset >= (s32)0x02000000))				offset = get_module_plt(module, loc,							offset + loc + 8)					 - loc - 8; 			if (offset <= (s32)0xfe000000 ||			    offset >= (s32)0x02000000) {				pr_err("%s: section %u reloc %u sym '%s': relocation %u out of range (%#lx -> %#x)\n",				       module->name, relindex, i, symname,				       ELF32_R_TYPE(rel->r_info), loc,				       sym->st_value);				return -ENOEXEC;			} 			offset >>= 2;			offset &= 0x00ffffff; 			*(u32 *)loc &= __opcode_to_mem_arm(0xff000000);			*(u32 *)loc |= __opcode_to_mem_arm(offset);			break; 	       case R_ARM_V4BX:		       /* Preserve Rm and the condition code. Alter			* other bits to re-code instruction as			* MOV PC,Rm.			*/		       *(u32 *)loc &= __opcode_to_mem_arm(0xf000000f);		       *(u32 *)loc |= __opcode_to_mem_arm(0x01a0f000);		       break; 		case R_ARM_PREL31:			offset = (*(s32 *)loc << 1) >> 1; /* sign extend */			offset += sym->st_value - loc;			if (offset >= 0x40000000 || offset < -0x40000000) {				pr_err("%s: section %u reloc %u sym '%s': relocation %u out of range (%#lx -> %#x)\n",				       module->name, relindex, i, symname,				       ELF32_R_TYPE(rel->r_info), loc,				       sym->st_value);				return -ENOEXEC;			}			*(u32 *)loc &= 0x80000000;			*(u32 *)loc |= offset & 0x7fffffff;			break; 		case R_ARM_MOVW_ABS_NC:		case R_ARM_MOVT_ABS:			offset = tmp = __mem_to_opcode_arm(*(u32 *)loc);			offset = ((offset & 0xf0000) >> 4) | (offset & 0xfff);			offset = (offset ^ 0x8000) - 0x8000; 			offset += sym->st_value;			if (ELF32_R_TYPE(rel->r_info) == R_ARM_MOVT_ABS)				offset >>= 16; 			tmp &= 0xfff0f000;			tmp |= ((offset & 0xf000) << 4) |				(offset & 0x0fff); 			*(u32 *)loc = __opcode_to_mem_arm(tmp);			break; #ifdef CONFIG_THUMB2_KERNEL		case R_ARM_THM_CALL:		case R_ARM_THM_JUMP24:			/*			 * For function symbols, only Thumb addresses are			 * allowed (no interworking).			 *			 * For non-function symbols, the destination			 * has no specific ARM/Thumb disposition, so			 * the branch is resolved under the assumption			 * that interworking is not required.			 */			if (ELF32_ST_TYPE(sym->st_info) == STT_FUNC &&			    !(sym->st_value & 1)) {				pr_err("%s: section %u reloc %u sym '%s': unsupported interworking call (Thumb -> ARM)\n",				       module->name, relindex, i, symname);				return -ENOEXEC;			} 			upper = __mem_to_opcode_thumb16(*(u16 *)loc);			lower = __mem_to_opcode_thumb16(*(u16 *)(loc + 2)); 			/*			 * 25 bit signed address range (Thumb-2 BL and B.W			 * instructions):			 *   S:I1:I2:imm10:imm11:0			 * where:			 *   S     = upper[10]   = offset[24]			 *   I1    = ~(J1 ^ S)   = offset[23]			 *   I2    = ~(J2 ^ S)   = offset[22]			 *   imm10 = upper[9:0]  = offset[21:12]			 *   imm11 = lower[10:0] = offset[11:1]			 *   J1    = lower[13]			 *   J2    = lower[11]			 */			sign = (upper >> 10) & 1;			j1 = (lower >> 13) & 1;			j2 = (lower >> 11) & 1;			offset = (sign << 24) | ((~(j1 ^ sign) & 1) << 23) |				((~(j2 ^ sign) & 1) << 22) |				((upper & 0x03ff) << 12) |				((lower & 0x07ff) << 1);			if (offset & 0x01000000)				offset -= 0x02000000;			offset += sym->st_value - loc; 			/*			 * Route through a PLT entry if 'offset' exceeds the			 * supported range.			 */			if (IS_ENABLED(CONFIG_ARM_MODULE_PLTS) &&			    (offset <= (s32)0xff000000 ||			     offset >= (s32)0x01000000))				offset = get_module_plt(module, loc,							offset + loc + 4)					 - loc - 4; 			if (offset <= (s32)0xff000000 ||			    offset >= (s32)0x01000000) {				pr_err("%s: section %u reloc %u sym '%s': relocation %u out of range (%#lx -> %#x)\n",				       module->name, relindex, i, symname,				       ELF32_R_TYPE(rel->r_info), loc,				       sym->st_value);				return -ENOEXEC;			} 			sign = (offset >> 24) & 1;			j1 = sign ^ (~(offset >> 23) & 1);			j2 = sign ^ (~(offset >> 22) & 1);			upper = (u16)((upper & 0xf800) | (sign << 10) |					    ((offset >> 12) & 0x03ff));			lower = (u16)((lower & 0xd000) |				      (j1 << 13) | (j2 << 11) |				      ((offset >> 1) & 0x07ff)); 			*(u16 *)loc = __opcode_to_mem_thumb16(upper);			*(u16 *)(loc + 2) = __opcode_to_mem_thumb16(lower);			break; 		case R_ARM_THM_MOVW_ABS_NC:		case R_ARM_THM_MOVT_ABS:			upper = __mem_to_opcode_thumb16(*(u16 *)loc);			lower = __mem_to_opcode_thumb16(*(u16 *)(loc + 2)); 			/*			 * MOVT/MOVW instructions encoding in Thumb-2:			 *			 * i	= upper[10]			 * imm4	= upper[3:0]			 * imm3	= lower[14:12]			 * imm8	= lower[7:0]			 *			 * imm16 = imm4:i:imm3:imm8			 */			offset = ((upper & 0x000f) << 12) |				((upper & 0x0400) << 1) |				((lower & 0x7000) >> 4) | (lower & 0x00ff);			offset = (offset ^ 0x8000) - 0x8000;			offset += sym->st_value; 			if (ELF32_R_TYPE(rel->r_info) == R_ARM_THM_MOVT_ABS)				offset >>= 16; 			upper = (u16)((upper & 0xfbf0) |				      ((offset & 0xf000) >> 12) |				      ((offset & 0x0800) >> 1));			lower = (u16)((lower & 0x8f00) |				      ((offset & 0x0700) << 4) |				      (offset & 0x00ff));			*(u16 *)loc = __opcode_to_mem_thumb16(upper);			*(u16 *)(loc + 2) = __opcode_to_mem_thumb16(lower);			break;#endif 		default:			pr_err("%s: unknown relocation: %u\n",			       module->name, ELF32_R_TYPE(rel->r_info));			return -ENOEXEC;		}	}	return 0;} struct mod_unwind_map {	const Elf_Shdr *unw_sec;	const Elf_Shdr *txt_sec;}; static const Elf_Shdr *find_mod_section(const Elf32_Ehdr *hdr,	const Elf_Shdr *sechdrs, const char *name){	const Elf_Shdr *s, *se;	const char *secstrs = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset; 	for (s = sechdrs, se = sechdrs + hdr->e_shnum; s < se; s++)		if (strcmp(name, secstrs + s->sh_name) == 0)			return s; 	return NULL;} extern void fixup_pv_table(const void *, unsigned long);extern void fixup_smp(const void *, unsigned long); int module_finalize(const Elf32_Ehdr *hdr, const Elf_Shdr *sechdrs,		    struct module *mod){	const Elf_Shdr *s = NULL;#ifdef CONFIG_ARM_UNWIND	const char *secstrs = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;	const Elf_Shdr *sechdrs_end = sechdrs + hdr->e_shnum;	struct mod_unwind_map maps[ARM_SEC_MAX];	int i; 	memset(maps, 0, sizeof(maps)); 	for (s = sechdrs; s < sechdrs_end; s++) {		const char *secname = secstrs + s->sh_name; 		if (!(s->sh_flags & SHF_ALLOC))			continue; 		if (strcmp(".ARM.exidx.init.text", secname) == 0)			maps[ARM_SEC_INIT].unw_sec = s;		else if (strcmp(".ARM.exidx", secname) == 0)			maps[ARM_SEC_CORE].unw_sec = s;		else if (strcmp(".ARM.exidx.exit.text", secname) == 0)			maps[ARM_SEC_EXIT].unw_sec = s;		else if (strcmp(".ARM.exidx.text.unlikely", secname) == 0)			maps[ARM_SEC_UNLIKELY].unw_sec = s;		else if (strcmp(".ARM.exidx.text.hot", secname) == 0)			maps[ARM_SEC_HOT].unw_sec = s;		else if (strcmp(".init.text", secname) == 0)			maps[ARM_SEC_INIT].txt_sec = s;		else if (strcmp(".text", secname) == 0)			maps[ARM_SEC_CORE].txt_sec = s;		else if (strcmp(".exit.text", secname) == 0)			maps[ARM_SEC_EXIT].txt_sec = s;		else if (strcmp(".text.unlikely", secname) == 0)			maps[ARM_SEC_UNLIKELY].txt_sec = s;		else if (strcmp(".text.hot", secname) == 0)			maps[ARM_SEC_HOT].txt_sec = s;	} 	for (i = 0; i < ARM_SEC_MAX; i++)		if (maps[i].unw_sec && maps[i].txt_sec)			mod->arch.unwind[i] =				unwind_table_add(maps[i].unw_sec->sh_addr,					         maps[i].unw_sec->sh_size,					         maps[i].txt_sec->sh_addr,					         maps[i].txt_sec->sh_size);#endif#ifdef CONFIG_ARM_PATCH_PHYS_VIRT	s = find_mod_section(hdr, sechdrs, ".pv_table");	if (s)		fixup_pv_table((void *)s->sh_addr, s->sh_size);#endif	s = find_mod_section(hdr, sechdrs, ".alt.smp.init");	if (s && !is_smp())#ifdef CONFIG_SMP_ON_UP		fixup_smp((void *)s->sh_addr, s->sh_size);#else		return -EINVAL;#endif	return 0;} voidmodule_arch_cleanup(struct module *mod){#ifdef CONFIG_ARM_UNWIND	int i; 	for (i = 0; i < ARM_SEC_MAX; i++)		if (mod->arch.unwind[i])			unwind_table_del(mod->arch.unwind[i]);#endif}