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-rw-r--r--mm/kasan/kasan.c22
-rw-r--r--mm/kasan/kasan_init.c15
-rw-r--r--mm/kasan/quarantine.c95
-rw-r--r--mm/kasan/report.c5
4 files changed, 82 insertions, 55 deletions
diff --git a/mm/kasan/kasan.c b/mm/kasan/kasan.c
index 0e9505f66ec1..98b27195e38b 100644
--- a/mm/kasan/kasan.c
+++ b/mm/kasan/kasan.c
@@ -29,6 +29,7 @@
#include <linux/module.h>
#include <linux/printk.h>
#include <linux/sched.h>
+#include <linux/sched/task_stack.h>
#include <linux/slab.h>
#include <linux/stacktrace.h>
#include <linux/string.h>
@@ -39,6 +40,16 @@
#include "kasan.h"
#include "../slab.h"
+void kasan_enable_current(void)
+{
+ current->kasan_depth++;
+}
+
+void kasan_disable_current(void)
+{
+ current->kasan_depth--;
+}
+
/*
* Poisons the shadow memory for 'size' bytes starting from 'addr'.
* Memory addresses should be aligned to KASAN_SHADOW_SCALE_SIZE.
@@ -80,7 +91,14 @@ void kasan_unpoison_task_stack(struct task_struct *task)
/* Unpoison the stack for the current task beyond a watermark sp value. */
asmlinkage void kasan_unpoison_task_stack_below(const void *watermark)
{
- __kasan_unpoison_stack(current, watermark);
+ /*
+ * Calculate the task stack base address. Avoid using 'current'
+ * because this function is called by early resume code which hasn't
+ * yet set up the percpu register (%gs).
+ */
+ void *base = (void *)((unsigned long)watermark & ~(THREAD_SIZE - 1));
+
+ kasan_unpoison_shadow(base, watermark - base);
}
/*
@@ -428,7 +446,7 @@ void kasan_cache_shrink(struct kmem_cache *cache)
quarantine_remove_cache(cache);
}
-void kasan_cache_destroy(struct kmem_cache *cache)
+void kasan_cache_shutdown(struct kmem_cache *cache)
{
quarantine_remove_cache(cache);
}
diff --git a/mm/kasan/kasan_init.c b/mm/kasan/kasan_init.c
index 3f9a41cf0ac6..31238dad85fb 100644
--- a/mm/kasan/kasan_init.c
+++ b/mm/kasan/kasan_init.c
@@ -15,6 +15,7 @@
#include <linux/kasan.h>
#include <linux/kernel.h>
#include <linux/memblock.h>
+#include <linux/mm.h>
#include <linux/pfn.h>
#include <asm/page.h>
@@ -49,7 +50,7 @@ static void __init zero_pte_populate(pmd_t *pmd, unsigned long addr,
pte_t *pte = pte_offset_kernel(pmd, addr);
pte_t zero_pte;
- zero_pte = pfn_pte(PFN_DOWN(__pa(kasan_zero_page)), PAGE_KERNEL);
+ zero_pte = pfn_pte(PFN_DOWN(__pa_symbol(kasan_zero_page)), PAGE_KERNEL);
zero_pte = pte_wrprotect(zero_pte);
while (addr + PAGE_SIZE <= end) {
@@ -69,7 +70,7 @@ static void __init zero_pmd_populate(pud_t *pud, unsigned long addr,
next = pmd_addr_end(addr, end);
if (IS_ALIGNED(addr, PMD_SIZE) && end - addr >= PMD_SIZE) {
- pmd_populate_kernel(&init_mm, pmd, kasan_zero_pte);
+ pmd_populate_kernel(&init_mm, pmd, lm_alias(kasan_zero_pte));
continue;
}
@@ -92,9 +93,9 @@ static void __init zero_pud_populate(pgd_t *pgd, unsigned long addr,
if (IS_ALIGNED(addr, PUD_SIZE) && end - addr >= PUD_SIZE) {
pmd_t *pmd;
- pud_populate(&init_mm, pud, kasan_zero_pmd);
+ pud_populate(&init_mm, pud, lm_alias(kasan_zero_pmd));
pmd = pmd_offset(pud, addr);
- pmd_populate_kernel(&init_mm, pmd, kasan_zero_pte);
+ pmd_populate_kernel(&init_mm, pmd, lm_alias(kasan_zero_pte));
continue;
}
@@ -135,11 +136,11 @@ void __init kasan_populate_zero_shadow(const void *shadow_start,
* puds,pmds, so pgd_populate(), pud_populate()
* is noops.
*/
- pgd_populate(&init_mm, pgd, kasan_zero_pud);
+ pgd_populate(&init_mm, pgd, lm_alias(kasan_zero_pud));
pud = pud_offset(pgd, addr);
- pud_populate(&init_mm, pud, kasan_zero_pmd);
+ pud_populate(&init_mm, pud, lm_alias(kasan_zero_pmd));
pmd = pmd_offset(pud, addr);
- pmd_populate_kernel(&init_mm, pmd, kasan_zero_pte);
+ pmd_populate_kernel(&init_mm, pmd, lm_alias(kasan_zero_pte));
continue;
}
diff --git a/mm/kasan/quarantine.c b/mm/kasan/quarantine.c
index baabaad4a4aa..6f1ed1630873 100644
--- a/mm/kasan/quarantine.c
+++ b/mm/kasan/quarantine.c
@@ -86,24 +86,9 @@ static void qlist_move_all(struct qlist_head *from, struct qlist_head *to)
qlist_init(from);
}
-static void qlist_move(struct qlist_head *from, struct qlist_node *last,
- struct qlist_head *to, size_t size)
-{
- if (unlikely(last == from->tail)) {
- qlist_move_all(from, to);
- return;
- }
- if (qlist_empty(to))
- to->head = from->head;
- else
- to->tail->next = from->head;
- to->tail = last;
- from->head = last->next;
- last->next = NULL;
- from->bytes -= size;
- to->bytes += size;
-}
-
+#define QUARANTINE_PERCPU_SIZE (1 << 20)
+#define QUARANTINE_BATCHES \
+ (1024 > 4 * CONFIG_NR_CPUS ? 1024 : 4 * CONFIG_NR_CPUS)
/*
* The object quarantine consists of per-cpu queues and a global queue,
@@ -111,11 +96,22 @@ static void qlist_move(struct qlist_head *from, struct qlist_node *last,
*/
static DEFINE_PER_CPU(struct qlist_head, cpu_quarantine);
-static struct qlist_head global_quarantine;
+/* Round-robin FIFO array of batches. */
+static struct qlist_head global_quarantine[QUARANTINE_BATCHES];
+static int quarantine_head;
+static int quarantine_tail;
+/* Total size of all objects in global_quarantine across all batches. */
+static unsigned long quarantine_size;
static DEFINE_SPINLOCK(quarantine_lock);
/* Maximum size of the global queue. */
-static unsigned long quarantine_size;
+static unsigned long quarantine_max_size;
+
+/*
+ * Target size of a batch in global_quarantine.
+ * Usually equal to QUARANTINE_PERCPU_SIZE unless we have too much RAM.
+ */
+static unsigned long quarantine_batch_size;
/*
* The fraction of physical memory the quarantine is allowed to occupy.
@@ -124,9 +120,6 @@ static unsigned long quarantine_size;
*/
#define QUARANTINE_FRACTION 32
-#define QUARANTINE_LOW_SIZE (READ_ONCE(quarantine_size) * 3 / 4)
-#define QUARANTINE_PERCPU_SIZE (1 << 20)
-
static struct kmem_cache *qlink_to_cache(struct qlist_node *qlink)
{
return virt_to_head_page(qlink)->slab_cache;
@@ -191,21 +184,30 @@ void quarantine_put(struct kasan_free_meta *info, struct kmem_cache *cache)
if (unlikely(!qlist_empty(&temp))) {
spin_lock_irqsave(&quarantine_lock, flags);
- qlist_move_all(&temp, &global_quarantine);
+ WRITE_ONCE(quarantine_size, quarantine_size + temp.bytes);
+ qlist_move_all(&temp, &global_quarantine[quarantine_tail]);
+ if (global_quarantine[quarantine_tail].bytes >=
+ READ_ONCE(quarantine_batch_size)) {
+ int new_tail;
+
+ new_tail = quarantine_tail + 1;
+ if (new_tail == QUARANTINE_BATCHES)
+ new_tail = 0;
+ if (new_tail != quarantine_head)
+ quarantine_tail = new_tail;
+ }
spin_unlock_irqrestore(&quarantine_lock, flags);
}
}
void quarantine_reduce(void)
{
- size_t new_quarantine_size, percpu_quarantines;
+ size_t total_size, new_quarantine_size, percpu_quarantines;
unsigned long flags;
struct qlist_head to_free = QLIST_INIT;
- size_t size_to_free = 0;
- struct qlist_node *last;
- if (likely(READ_ONCE(global_quarantine.bytes) <=
- READ_ONCE(quarantine_size)))
+ if (likely(READ_ONCE(quarantine_size) <=
+ READ_ONCE(quarantine_max_size)))
return;
spin_lock_irqsave(&quarantine_lock, flags);
@@ -214,24 +216,23 @@ void quarantine_reduce(void)
* Update quarantine size in case of hotplug. Allocate a fraction of
* the installed memory to quarantine minus per-cpu queue limits.
*/
- new_quarantine_size = (READ_ONCE(totalram_pages) << PAGE_SHIFT) /
+ total_size = (READ_ONCE(totalram_pages) << PAGE_SHIFT) /
QUARANTINE_FRACTION;
percpu_quarantines = QUARANTINE_PERCPU_SIZE * num_online_cpus();
- new_quarantine_size = (new_quarantine_size < percpu_quarantines) ?
- 0 : new_quarantine_size - percpu_quarantines;
- WRITE_ONCE(quarantine_size, new_quarantine_size);
-
- last = global_quarantine.head;
- while (last) {
- struct kmem_cache *cache = qlink_to_cache(last);
-
- size_to_free += cache->size;
- if (!last->next || size_to_free >
- global_quarantine.bytes - QUARANTINE_LOW_SIZE)
- break;
- last = last->next;
+ new_quarantine_size = (total_size < percpu_quarantines) ?
+ 0 : total_size - percpu_quarantines;
+ WRITE_ONCE(quarantine_max_size, new_quarantine_size);
+ /* Aim at consuming at most 1/2 of slots in quarantine. */
+ WRITE_ONCE(quarantine_batch_size, max((size_t)QUARANTINE_PERCPU_SIZE,
+ 2 * total_size / QUARANTINE_BATCHES));
+
+ if (likely(quarantine_size > quarantine_max_size)) {
+ qlist_move_all(&global_quarantine[quarantine_head], &to_free);
+ WRITE_ONCE(quarantine_size, quarantine_size - to_free.bytes);
+ quarantine_head++;
+ if (quarantine_head == QUARANTINE_BATCHES)
+ quarantine_head = 0;
}
- qlist_move(&global_quarantine, last, &to_free, size_to_free);
spin_unlock_irqrestore(&quarantine_lock, flags);
@@ -273,15 +274,17 @@ static void per_cpu_remove_cache(void *arg)
qlist_free_all(&to_free, cache);
}
+/* Free all quarantined objects belonging to cache. */
void quarantine_remove_cache(struct kmem_cache *cache)
{
- unsigned long flags;
+ unsigned long flags, i;
struct qlist_head to_free = QLIST_INIT;
on_each_cpu(per_cpu_remove_cache, cache, 1);
spin_lock_irqsave(&quarantine_lock, flags);
- qlist_move_cache(&global_quarantine, &to_free, cache);
+ for (i = 0; i < QUARANTINE_BATCHES; i++)
+ qlist_move_cache(&global_quarantine[i], &to_free, cache);
spin_unlock_irqrestore(&quarantine_lock, flags);
qlist_free_all(&to_free, cache);
diff --git a/mm/kasan/report.c b/mm/kasan/report.c
index 073325aedc68..f479365530b6 100644
--- a/mm/kasan/report.c
+++ b/mm/kasan/report.c
@@ -13,6 +13,7 @@
*
*/
+#include <linux/ftrace.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/printk.h>
@@ -136,6 +137,8 @@ static void kasan_end_report(unsigned long *flags)
pr_err("==================================================================\n");
add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE);
spin_unlock_irqrestore(&report_lock, *flags);
+ if (panic_on_warn)
+ panic("panic_on_warn set ...\n");
kasan_enable_current();
}
@@ -298,6 +301,8 @@ void kasan_report(unsigned long addr, size_t size,
if (likely(!kasan_report_enabled()))
return;
+ disable_trace_on_warning();
+
info.access_addr = (void *)addr;
info.access_size = size;
info.is_write = is_write;
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-11 12:42:03 +0000