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-rw-r--r--mm/kasan/hw_tags.c77
-rw-r--r--mm/kasan/init.c23
2 files changed, 45 insertions, 55 deletions
diff --git a/mm/kasan/hw_tags.c b/mm/kasan/hw_tags.c
index 55bd6f09c70f..e529428e7a11 100644
--- a/mm/kasan/hw_tags.c
+++ b/mm/kasan/hw_tags.c
@@ -19,11 +19,10 @@
#include "kasan.h"
-enum kasan_arg_mode {
- KASAN_ARG_MODE_DEFAULT,
- KASAN_ARG_MODE_OFF,
- KASAN_ARG_MODE_PROD,
- KASAN_ARG_MODE_FULL,
+enum kasan_arg {
+ KASAN_ARG_DEFAULT,
+ KASAN_ARG_OFF,
+ KASAN_ARG_ON,
};
enum kasan_arg_stacktrace {
@@ -38,7 +37,7 @@ enum kasan_arg_fault {
KASAN_ARG_FAULT_PANIC,
};
-static enum kasan_arg_mode kasan_arg_mode __ro_after_init;
+static enum kasan_arg kasan_arg __ro_after_init;
static enum kasan_arg_stacktrace kasan_arg_stacktrace __ro_after_init;
static enum kasan_arg_fault kasan_arg_fault __ro_after_init;
@@ -52,26 +51,24 @@ DEFINE_STATIC_KEY_FALSE(kasan_flag_stacktrace);
/* Whether panic or disable tag checking on fault. */
bool kasan_flag_panic __ro_after_init;
-/* kasan.mode=off/prod/full */
-static int __init early_kasan_mode(char *arg)
+/* kasan=off/on */
+static int __init early_kasan_flag(char *arg)
{
if (!arg)
return -EINVAL;
if (!strcmp(arg, "off"))
- kasan_arg_mode = KASAN_ARG_MODE_OFF;
- else if (!strcmp(arg, "prod"))
- kasan_arg_mode = KASAN_ARG_MODE_PROD;
- else if (!strcmp(arg, "full"))
- kasan_arg_mode = KASAN_ARG_MODE_FULL;
+ kasan_arg = KASAN_ARG_OFF;
+ else if (!strcmp(arg, "on"))
+ kasan_arg = KASAN_ARG_ON;
else
return -EINVAL;
return 0;
}
-early_param("kasan.mode", early_kasan_mode);
+early_param("kasan", early_kasan_flag);
-/* kasan.stack=off/on */
+/* kasan.stacktrace=off/on */
static int __init early_kasan_flag_stacktrace(char *arg)
{
if (!arg)
@@ -113,8 +110,8 @@ void kasan_init_hw_tags_cpu(void)
* as this function is only called for MTE-capable hardware.
*/
- /* If KASAN is disabled, do nothing. */
- if (kasan_arg_mode == KASAN_ARG_MODE_OFF)
+ /* If KASAN is disabled via command line, don't initialize it. */
+ if (kasan_arg == KASAN_ARG_OFF)
return;
hw_init_tags(KASAN_TAG_MAX);
@@ -124,43 +121,28 @@ void kasan_init_hw_tags_cpu(void)
/* kasan_init_hw_tags() is called once on boot CPU. */
void __init kasan_init_hw_tags(void)
{
- /* If hardware doesn't support MTE, do nothing. */
+ /* If hardware doesn't support MTE, don't initialize KASAN. */
if (!system_supports_mte())
return;
- /* Choose KASAN mode if kasan boot parameter is not provided. */
- if (kasan_arg_mode == KASAN_ARG_MODE_DEFAULT) {
- if (IS_ENABLED(CONFIG_DEBUG_KERNEL))
- kasan_arg_mode = KASAN_ARG_MODE_FULL;
- else
- kasan_arg_mode = KASAN_ARG_MODE_PROD;
- }
-
- /* Preset parameter values based on the mode. */
- switch (kasan_arg_mode) {
- case KASAN_ARG_MODE_DEFAULT:
- /* Shouldn't happen as per the check above. */
- WARN_ON(1);
- return;
- case KASAN_ARG_MODE_OFF:
- /* If KASAN is disabled, do nothing. */
+ /* If KASAN is disabled via command line, don't initialize it. */
+ if (kasan_arg == KASAN_ARG_OFF)
return;
- case KASAN_ARG_MODE_PROD:
- static_branch_enable(&kasan_flag_enabled);
- break;
- case KASAN_ARG_MODE_FULL:
- static_branch_enable(&kasan_flag_enabled);
- static_branch_enable(&kasan_flag_stacktrace);
- break;
- }
- /* Now, optionally override the presets. */
+ /* Enable KASAN. */
+ static_branch_enable(&kasan_flag_enabled);
switch (kasan_arg_stacktrace) {
case KASAN_ARG_STACKTRACE_DEFAULT:
+ /*
+ * Default to enabling stack trace collection for
+ * debug kernels.
+ */
+ if (IS_ENABLED(CONFIG_DEBUG_KERNEL))
+ static_branch_enable(&kasan_flag_stacktrace);
break;
case KASAN_ARG_STACKTRACE_OFF:
- static_branch_disable(&kasan_flag_stacktrace);
+ /* Do nothing, kasan_flag_stacktrace keeps its default value. */
break;
case KASAN_ARG_STACKTRACE_ON:
static_branch_enable(&kasan_flag_stacktrace);
@@ -169,11 +151,16 @@ void __init kasan_init_hw_tags(void)
switch (kasan_arg_fault) {
case KASAN_ARG_FAULT_DEFAULT:
+ /*
+ * Default to no panic on report.
+ * Do nothing, kasan_flag_panic keeps its default value.
+ */
break;
case KASAN_ARG_FAULT_REPORT:
- kasan_flag_panic = false;
+ /* Do nothing, kasan_flag_panic keeps its default value. */
break;
case KASAN_ARG_FAULT_PANIC:
+ /* Enable panic on report. */
kasan_flag_panic = true;
break;
}
diff --git a/mm/kasan/init.c b/mm/kasan/init.c
index 7ca0b92d5886..c4605ac9837b 100644
--- a/mm/kasan/init.c
+++ b/mm/kasan/init.c
@@ -373,9 +373,10 @@ static void kasan_remove_pmd_table(pmd_t *pmd, unsigned long addr,
if (kasan_pte_table(*pmd)) {
if (IS_ALIGNED(addr, PMD_SIZE) &&
- IS_ALIGNED(next, PMD_SIZE))
+ IS_ALIGNED(next, PMD_SIZE)) {
pmd_clear(pmd);
- continue;
+ continue;
+ }
}
pte = pte_offset_kernel(pmd, addr);
kasan_remove_pte_table(pte, addr, next);
@@ -398,9 +399,10 @@ static void kasan_remove_pud_table(pud_t *pud, unsigned long addr,
if (kasan_pmd_table(*pud)) {
if (IS_ALIGNED(addr, PUD_SIZE) &&
- IS_ALIGNED(next, PUD_SIZE))
+ IS_ALIGNED(next, PUD_SIZE)) {
pud_clear(pud);
- continue;
+ continue;
+ }
}
pmd = pmd_offset(pud, addr);
pmd_base = pmd_offset(pud, 0);
@@ -424,9 +426,10 @@ static void kasan_remove_p4d_table(p4d_t *p4d, unsigned long addr,
if (kasan_pud_table(*p4d)) {
if (IS_ALIGNED(addr, P4D_SIZE) &&
- IS_ALIGNED(next, P4D_SIZE))
+ IS_ALIGNED(next, P4D_SIZE)) {
p4d_clear(p4d);
- continue;
+ continue;
+ }
}
pud = pud_offset(p4d, addr);
kasan_remove_pud_table(pud, addr, next);
@@ -457,9 +460,10 @@ void kasan_remove_zero_shadow(void *start, unsigned long size)
if (kasan_p4d_table(*pgd)) {
if (IS_ALIGNED(addr, PGDIR_SIZE) &&
- IS_ALIGNED(next, PGDIR_SIZE))
+ IS_ALIGNED(next, PGDIR_SIZE)) {
pgd_clear(pgd);
- continue;
+ continue;
+ }
}
p4d = p4d_offset(pgd, addr);
@@ -482,7 +486,6 @@ int kasan_add_zero_shadow(void *start, unsigned long size)
ret = kasan_populate_early_shadow(shadow_start, shadow_end);
if (ret)
- kasan_remove_zero_shadow(shadow_start,
- size >> KASAN_SHADOW_SCALE_SHIFT);
+ kasan_remove_zero_shadow(start, size);
return ret;
}
generated by cgit v1.2.3-70-g09d2 (git 2.47.1) at 2024-12-29 11:17:28 +0000