From: "Mike Rapoport (IBM)" <rppt@xxxxxxxxxx>
Enable execmem's cache of PMD_SIZE'ed pages mapped as ROX for module
text allocations.
Signed-off-by: Mike Rapoport (IBM) <rppt@xxxxxxxxxx>
---
arch/x86/mm/init.c | 29 +++++++++++++++++++++++++----
1 file changed, 25 insertions(+), 4 deletions(-)
diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c
index 8e8cd0de3af6..049a8b4c64e2 100644
--- a/arch/x86/mm/init.c
+++ b/arch/x86/mm/init.c
@@ -1102,9 +1102,23 @@ unsigned long arch_max_swapfile_size(void)
#endif
#ifdef CONFIG_EXECMEM
+static void execmem_invalidate(void *ptr, size_t size, bool writeable)
+{
+ /* fill memory with INT3 instructions */
+ if (writeable)
+ memset(ptr, 0xcc, size);
+ else
+ text_poke_set(ptr, 0xcc, size);
+}
+
static struct execmem_info execmem_info __ro_after_init = {
+ .invalidate = execmem_invalidate,
.ranges = {
- [EXECMEM_DEFAULT] = {
+ [EXECMEM_MODULE_TEXT] = {
+ .flags = EXECMEM_KASAN_SHADOW | EXECMEM_ROX_CACHE,
+ .alignment = MODULE_ALIGN,
+ },
+ [EXECMEM_KPROBES...EXECMEM_MODULE_DATA] = {
.flags = EXECMEM_KASAN_SHADOW,
.alignment = MODULE_ALIGN,
},
@@ -1119,9 +1133,16 @@ struct execmem_info __init *execmem_arch_setup(void)
offset = get_random_u32_inclusive(1, 1024) * PAGE_SIZE;
start = MODULES_VADDR + offset;
- execmem_info.ranges[EXECMEM_DEFAULT].start = start;
- execmem_info.ranges[EXECMEM_DEFAULT].end = MODULES_END;
- execmem_info.ranges[EXECMEM_DEFAULT].pgprot = PAGE_KERNEL;
+
+ for (int i = EXECMEM_MODULE_TEXT; i < EXECMEM_TYPE_MAX; i++) {
+ struct execmem_range *r = &execmem_info.ranges[i];
+
+ r->start = start;
+ r->end = MODULES_END;
+ r->pgprot = PAGE_KERNEL;
+ }
+
+ execmem_info.ranges[EXECMEM_MODULE_TEXT].pgprot = PAGE_KERNEL_ROX;
return &execmem_info;
}
--
2.43.0
