Patch "arm64: fix types in copy_highpage()" has been added to the 5.15-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    arm64: fix types in copy_highpage()

to the 5.15-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     arm64-fix-types-in-copy_highpage.patch
and it can be found in the queue-5.15 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 9849e7d6f25c9877b78ecfbfd350ae9682d16e57
Author: Tong Tiangen <tongtiangen@xxxxxxxxxx>
Date:   Wed Apr 20 03:04:13 2022 +0000

    arm64: fix types in copy_highpage()
    
    [ Upstream commit 921d161f15d6b090599f6a8c23f131969edbd1fa ]
    
    In copy_highpage() the `kto` and `kfrom` local variables are pointers to
    struct page, but these are used to hold arbitrary pointers to kernel memory
    . Each call to page_address() returns a void pointer to memory associated
    with the relevant page, and copy_page() expects void pointers to this
    memory.
    
    This inconsistency was introduced in commit 2563776b41c3 ("arm64: mte:
    Tags-aware copy_{user_,}highpage() implementations") and while this
    doesn't appear to be harmful in practice it is clearly wrong.
    
    Correct this by making `kto` and `kfrom` void pointers.
    
    Fixes: 2563776b41c3 ("arm64: mte: Tags-aware copy_{user_,}highpage() implementations")
    Signed-off-by: Tong Tiangen <tongtiangen@xxxxxxxxxx>
    Acked-by: Mark Rutland <mark.rutland@xxxxxxx>
    Reviewed-by: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx>
    Link: https://lore.kernel.org/r/20220420030418.3189040-3-tongtiangen@xxxxxxxxxx
    Signed-off-by: Catalin Marinas <catalin.marinas@xxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/arch/arm64/mm/copypage.c b/arch/arm64/mm/copypage.c
index b5447e53cd73..0dea80bf6de4 100644
--- a/arch/arm64/mm/copypage.c
+++ b/arch/arm64/mm/copypage.c
@@ -16,8 +16,8 @@
 
 void copy_highpage(struct page *to, struct page *from)
 {
-	struct page *kto = page_address(to);
-	struct page *kfrom = page_address(from);
+	void *kto = page_address(to);
+	void *kfrom = page_address(from);
 
 	copy_page(kto, kfrom);