 82fab442f5
			
		
	
	
	82fab442f5
	
	
	
		
			
			In commitd0a21265dfDavid Rientjes unified various archs' module_alloc implementation (including x86) and removed the graduitous shortcut for size == 0. Then, in commitde7d2b567d, Joe Perches added a warning for zero-length vmallocs, which can happen without kallsyms on modules with no init sections (eg. zlib_deflate). Fix this once and for all; the module code has to handle zero length anyway, so get it right at the caller and remove the now-gratuitous checks within the arch-specific module_alloc implementations. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=42608 Reported-by: Conrad Kostecki <ConiKost@gmx.de> Cc: David Rientjes <rientjes@google.com> Cc: Joe Perches <joe@perches.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
		
			
				
	
	
		
			114 lines
		
	
	
	
		
			2.8 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			114 lines
		
	
	
	
		
			2.8 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * linux/arch/unicore32/kernel/module.c
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|  *
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|  * Code specific to PKUnity SoC and UniCore ISA
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|  *
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|  * Copyright (C) 2001-2010 GUAN Xue-tao
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|  *
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|  * This program is free software; you can redistribute it and/or modify
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|  * it under the terms of the GNU General Public License version 2 as
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|  * published by the Free Software Foundation.
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|  */
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| #include <linux/module.h>
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| #include <linux/moduleloader.h>
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| #include <linux/kernel.h>
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| #include <linux/mm.h>
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| #include <linux/elf.h>
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| #include <linux/vmalloc.h>
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| #include <linux/fs.h>
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| #include <linux/string.h>
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| #include <linux/gfp.h>
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| 
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| #include <asm/pgtable.h>
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| #include <asm/sections.h>
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| 
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| void *module_alloc(unsigned long size)
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| {
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| 	struct vm_struct *area;
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| 
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| 	size = PAGE_ALIGN(size);
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| 	area = __get_vm_area(size, VM_ALLOC, MODULES_VADDR, MODULES_END);
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| 	if (!area)
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| 		return NULL;
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| 
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| 	return __vmalloc_area(area, GFP_KERNEL, PAGE_KERNEL_EXEC);
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| }
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| 
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| int
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| apply_relocate(Elf32_Shdr *sechdrs, const char *strtab, unsigned int symindex,
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| 	       unsigned int relindex, struct module *module)
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| {
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| 	Elf32_Shdr *symsec = sechdrs + symindex;
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| 	Elf32_Shdr *relsec = sechdrs + relindex;
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| 	Elf32_Shdr *dstsec = sechdrs + relsec->sh_info;
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| 	Elf32_Rel *rel = (void *)relsec->sh_addr;
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| 	unsigned int i;
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| 
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| 	for (i = 0; i < relsec->sh_size / sizeof(Elf32_Rel); i++, rel++) {
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| 		unsigned long loc;
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| 		Elf32_Sym *sym;
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| 		s32 offset;
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| 
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| 		offset = ELF32_R_SYM(rel->r_info);
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| 		if (offset < 0 || offset >
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| 				(symsec->sh_size / sizeof(Elf32_Sym))) {
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| 			printk(KERN_ERR "%s: bad relocation, "
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| 					"section %d reloc %d\n",
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| 					module->name, relindex, i);
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| 			return -ENOEXEC;
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| 		}
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| 
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| 		sym = ((Elf32_Sym *)symsec->sh_addr) + offset;
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| 
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| 		if (rel->r_offset < 0 || rel->r_offset >
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| 				dstsec->sh_size - sizeof(u32)) {
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| 			printk(KERN_ERR "%s: out of bounds relocation, "
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| 				"section %d reloc %d offset %d size %d\n",
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| 				module->name, relindex, i, rel->r_offset,
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| 				dstsec->sh_size);
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| 			return -ENOEXEC;
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| 		}
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| 
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| 		loc = dstsec->sh_addr + rel->r_offset;
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| 
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| 		switch (ELF32_R_TYPE(rel->r_info)) {
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| 		case R_UNICORE_NONE:
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| 			/* ignore */
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| 			break;
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| 
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| 		case R_UNICORE_ABS32:
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| 			*(u32 *)loc += sym->st_value;
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| 			break;
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| 
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| 		case R_UNICORE_PC24:
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| 		case R_UNICORE_CALL:
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| 		case R_UNICORE_JUMP24:
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| 			offset = (*(u32 *)loc & 0x00ffffff) << 2;
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| 			if (offset & 0x02000000)
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| 				offset -= 0x04000000;
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| 
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| 			offset += sym->st_value - loc;
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| 			if (offset & 3 ||
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| 			    offset <= (s32)0xfe000000 ||
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| 			    offset >= (s32)0x02000000) {
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| 				printk(KERN_ERR
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| 				       "%s: relocation out of range, section "
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| 				       "%d reloc %d sym '%s'\n", module->name,
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| 				       relindex, i, strtab + sym->st_name);
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| 				return -ENOEXEC;
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| 			}
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| 
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| 			offset >>= 2;
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| 
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| 			*(u32 *)loc &= 0xff000000;
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| 			*(u32 *)loc |= offset & 0x00ffffff;
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| 			break;
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| 
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| 		default:
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| 			printk(KERN_ERR "%s: unknown relocation: %u\n",
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| 			       module->name, ELF32_R_TYPE(rel->r_info));
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| 			return -ENOEXEC;
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| 		}
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| 	}
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| 	return 0;
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| }
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