+ kfence-kasan-make-kfence-compatible-with-kasan-fix.patch added to -mm tree

+ kfence-kasan-make-kfence-compatible-with-kasan-fix.patch added to -mm tree

[akpm]

The patch titled
     Subject: revert kasan-remove-kfence-leftovers
has been added to the -mm tree.  Its filename is
     kfence-kasan-make-kfence-compatible-with-kasan-fix.patch

This patch should soon appear at
    https://ozlabs.org/~akpm/mmots/broken-out/kfence-kasan-make-kfence-compatible-with-kasan-fix.patch
and later at
    https://ozlabs.org/~akpm/mmotm/broken-out/kfence-kasan-make-kfence-compatible-with-kasan-fix.patch

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*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***

The -mm tree is included into linux-next and is updated
there every 3-4 working days

------------------------------------------------------
From: Andrew Morton <akpm@linux-foundation.org>
Subject: revert kasan-remove-kfence-leftovers

Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Alexander Potapenko <glider@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/kasan/kasan.h  |    9 +++++++++
 mm/kasan/shadow.c |   13 +++++++++++++
 2 files changed, 22 insertions(+)

--- a/mm/kasan/kasan.h~kfence-kasan-make-kfence-compatible-with-kasan-fix
+++ a/mm/kasan/kasan.h
@@ -3,6 +3,7 @@
 #define __MM_KASAN_KASAN_H
 
 #include <linux/kasan.h>
+#include <linux/kfence.h>
 #include <linux/stackdepot.h>
 
 #ifdef CONFIG_KASAN_HW_TAGS
@@ -304,12 +305,20 @@ static inline u8 random_tag(void) { retu
 
 static inline void poison_range(const void *address, size_t size, u8 value)
 {
+	/* Skip KFENCE memory if called explicitly outside of sl*b. */
+	if (is_kfence_address(address))
+		return;
+
 	hw_set_mem_tag_range(kasan_reset_tag(address),
 			round_up(size, KASAN_GRANULE_SIZE), value);
 }
 
 static inline void unpoison_range(const void *address, size_t size)
 {
+	/* Skip KFENCE memory if called explicitly outside of sl*b. */
+	if (is_kfence_address(address))
+		return;
+
 	hw_set_mem_tag_range(kasan_reset_tag(address),
 			round_up(size, KASAN_GRANULE_SIZE), get_tag(address));
 }
--- a/mm/kasan/shadow.c~kfence-kasan-make-kfence-compatible-with-kasan-fix
+++ a/mm/kasan/shadow.c
@@ -13,6 +13,7 @@
 #include <linux/init.h>
 #include <linux/kasan.h>
 #include <linux/kernel.h>
+#include <linux/kfence.h>
 #include <linux/kmemleak.h>
 #include <linux/memory.h>
 #include <linux/mm.h>
@@ -84,6 +85,10 @@ void poison_range(const void *address, s
 	address = kasan_reset_tag(address);
 	size = round_up(size, KASAN_GRANULE_SIZE);
 
+	/* Skip KFENCE memory if called explicitly outside of sl*b. */
+	if (is_kfence_address(address))
+		return;
+
 	shadow_start = kasan_mem_to_shadow(address);
 	shadow_end = kasan_mem_to_shadow(address + size);
 
@@ -101,6 +106,14 @@ void unpoison_range(const void *address,
 	 */
 	address = kasan_reset_tag(address);
 
+	/*
+	 * Skip KFENCE memory if called explicitly outside of sl*b. Also note
+	 * that calls to ksize(), where size is not a multiple of machine-word
+	 * size, would otherwise poison the invalid portion of the word.
+	 */
+	if (is_kfence_address(address))
+		return;
+
 	poison_range(address, size, tag);
 
 	if (size & KASAN_GRANULE_MASK) {
_

Patches currently in -mm which might be from akpm@linux-foundation.org are

kasan-remove-kfence-leftovers.patch
mm.patch
mm-fix-initialization-of-struct-page-for-holes-in-memory-layout-checkpatch-fixes.patch
mm-vmstat-fix-proc-sys-vm-stat_refresh-generating-false-warnings-fix-2.patch
kfence-kasan-make-kfence-compatible-with-kasan-fix.patch
linux-next-rejects.patch
kmap-stupid-hacks-to-make-it-compile.patch
set_memory-allow-set_direct_map__noflush-for-multiple-pages-fix.patch
arch-mm-wire-up-memfd_secret-system-call-were-relevant-fix.patch
kernel-forkc-export-kernel_thread-to-modules.patch