s390/kasan: dynamic shadow mem allocation for modules

Move from modules area entire shadow memory preallocation to dynamic
allocation per module load.

This behaivior has been introduced for x86 with bebf56a1b: "This patch
also forces module_alloc() to return 8*PAGE_SIZE aligned address making
shadow memory handling ( kasan_module_alloc()/kasan_module_free() )
more simple. Such alignment guarantees that each shadow page backing
modules address space correspond to only one module_alloc() allocation"

Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This commit is contained in:
Vasily Gorbik
2017-11-17 18:22:24 +01:00
committed by Martin Schwidefsky
parent 0dac8f6bc3
commit 793213a82d
2 changed files with 14 additions and 12 deletions

View File

@@ -16,6 +16,7 @@
#include <linux/fs.h>
#include <linux/string.h>
#include <linux/kernel.h>
#include <linux/kasan.h>
#include <linux/moduleloader.h>
#include <linux/bug.h>
#include <asm/alternative.h>
@@ -32,12 +33,18 @@
void *module_alloc(unsigned long size)
{
void *p;
if (PAGE_ALIGN(size) > MODULES_LEN)
return NULL;
return __vmalloc_node_range(size, 1, MODULES_VADDR, MODULES_END,
GFP_KERNEL, PAGE_KERNEL_EXEC,
0, NUMA_NO_NODE,
__builtin_return_address(0));
p = __vmalloc_node_range(size, MODULE_ALIGN, MODULES_VADDR, MODULES_END,
GFP_KERNEL, PAGE_KERNEL_EXEC, 0, NUMA_NO_NODE,
__builtin_return_address(0));
if (p && (kasan_module_alloc(p, size) < 0)) {
vfree(p);
return NULL;
}
return p;
}
void module_arch_freeing_init(struct module *mod)