New subject: [PATCH OLK-5.10 02/31] kasan: fix conflict with page poisoning

28 Sep 2021

From: Zhenhua Huang zhenhuah@codeaurora.org
mainline inclusion
from mainline-v5.11-rc1
commit 7fb7ab6d618a4dc7ea3f3eafc92388a35b4f8894
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I49LXW
CVE: NA
-------------------------------------------------
Page owner of pages used by page owner itself used is missing on arm32
targets.  The reason is dummy_handle and failure_handle is not initialized
correctly.  Buddy allocator is used to initialize these two handles.
However, buddy allocator is not ready when page owner calls it.  This
change fixed that by initializing page owner after buddy initialization.
The working flow before and after this change are:
original logic:
 1. allocated memory for page_ext(using memblock).
 2. invoke the init callback of page_ext_ops like page_owner(using buddy
    allocator).
 3. initialize buddy.
after this change:
 1. allocated memory for page_ext(using memblock).
 2. initialize buddy.
 3. invoke the init callback of page_ext_ops like page_owner(using buddy
    allocator).
with the change, failure/dummy_handle can get its correct value and page
owner output for example has the one for page owner itself:
Page allocated via order 2, mask 0x6202c0(GFP_USER|__GFP_NOWARN),
  pid 1006, ts 67278156558 ns
  PFN 543776 type Unmovable Block 531 type Unmovable Flags 0x0()
    init_page_owner+0x28/0x2f8
    invoke_init_callbacks_flatmem+0x24/0x34
    start_kernel+0x33c/0x5d8
Link: https://lkml.kernel.org/r/1603104925-5888-1-git-send-email-zhenhuah@codeauro...
Signed-off-by: Zhenhua Huang zhenhuah@codeaurora.org
Acked-by: Vlastimil Babka vbabka@suse.cz
Cc: Joonsoo Kim iamjoonsoo.kim@lge.com
Signed-off-by: Andrew Morton akpm@linux-foundation.org
Signed-off-by: Linus Torvalds torvalds@linux-foundation.org
(cherry picked from commit 7fb7ab6d618a4dc7ea3f3eafc92388a35b4f8894)
Signed-off-by: Kefeng Wang wangkefeng.wang@huawei.com
Signed-off-by: Yuanzheng Song songyuanzheng@huawei.com
Reviewed-by: Kefeng Wang wangkefeng.wang@huawei.com
Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com
---
 include/linux/page_ext.h |  8 ++++++++
 init/main.c              |  2 ++
 mm/page_ext.c            | 10 ++++++++--
 3 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/include/linux/page_ext.h b/include/linux/page_ext.h
index cfce186f0c4e..aff81ba31bd8 100644
--- a/include/linux/page_ext.h
+++ b/include/linux/page_ext.h
@@ -44,8 +44,12 @@ static inline void page_ext_init_flatmem(void)
 {
 }
 extern void page_ext_init(void);
+static inline void page_ext_init_flatmem_late(void)
+{
+}
 #else
 extern void page_ext_init_flatmem(void);
+extern void page_ext_init_flatmem_late(void);
 static inline void page_ext_init(void)
 {
 }
@@ -76,6 +80,10 @@ static inline void page_ext_init(void)
 {
 }
+static inline void page_ext_init_flatmem_late(void)
+{
+}
+
 static inline void page_ext_init_flatmem(void)
 {
 }
diff --git a/init/main.c b/init/main.c
index fc0277a9e7a3..f6fe37a744b7 100644
--- a/init/main.c
+++ b/init/main.c
@@ -830,6 +830,8 @@ static void __init mm_init(void)
    init_debug_pagealloc();
    report_meminit();
    mem_init();
+	/* page_owner must be initialized after buddy is ready */
+	page_ext_init_flatmem_late();
    kmem_cache_init();
    kmemleak_init();
    pgtable_init();
diff --git a/mm/page_ext.c b/mm/page_ext.c
index cf931ebb58d7..df6f74aac8e1 100644
--- a/mm/page_ext.c
+++ b/mm/page_ext.c
@@ -99,12 +99,19 @@ static void __init invoke_init_callbacks(void)
    }
 }
+#ifndef CONFIG_SPARSEMEM
+void __init page_ext_init_flatmem_late(void)
+{
+	invoke_init_callbacks();
+}
+#endif
+
 static inline struct page_ext *get_entry(void *base, unsigned long index)
 {
    return base + page_ext_size * index;
 }
-#if !defined(CONFIG_SPARSEMEM)
+#ifndef CONFIG_SPARSEMEM
void __meminit pgdat_page_ext_init(struct pglist_data *pgdat)
@@ -177,7 +184,6 @@ void __init page_ext_init_flatmem(void)
    		goto fail;
    }
    pr_info("allocated %ld bytes of page_ext\n", total_usage);
-	invoke_init_callbacks();
    return;
fail:
-- 
2.20.1

    

[PATCH OLK-5.10 01/31] mm: fix page_owner initializing issue for arm32