setup: change init code sanitize pattern to 0xcc

Don't sanitize the init code region with zeros as these decode to valid instructions if %rax points to mapped memory. Instead use 0xcc which would trap if we ever would return to an address in that range. Signed-off-by: Mathias Krause <[email protected]>
KernelTestFramework · Oct 14, 2021 · 1d88eff · 1d88eff
1 parent b802348
commit 1d88eff
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/common/setup.c b/common/setup.c
@@ -178,7 +178,7 @@ void zap_boot_mappings(void) {
     for_each_memory_range (r) {
         if (r->base == VIRT_IDENT_BASE && IS_INIT_SECTION(r->name)) {
             if (strcmp(r->name, ".text.init"))
-                memset(r->start, 0, r->end - r->start);
+                memset(r->start, 0xcc, r->end - r->start);
 
             for (mfn_t mfn = virt_to_mfn(r->start); mfn < virt_to_mfn(r->end); mfn++) {
                 vunmap(mfn_to_virt(mfn), PAGE_ORDER_4K);