From a52b76b87462bb4c0086f32eabfdc61e13fdfc50 Mon Sep 17 00:00:00 2001
From: Kalesh Singh <kaleshsingh@google.com>
Date: Fri, 17 Nov 2023 14:50:46 -0800
Subject: [PATCH] ANDROID: 16K: mremap: __PAGE_ALIGN addr and len

In page-compat mode, mremap() syscalls must be at __PAGE_ALIGN-ed
addresses and of __PAGE_SIZE-multiple length.

Bug: 383389337
Bug: 315325080
Bug: 302403436
Change-Id: I796a423c75823d5e3ae25dd4e0855514cf5d27b8
Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
---
 mm/mremap.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/mm/mremap.c b/mm/mremap.c
index 4caf5f4d0529..1d3870467df6 100644
--- a/mm/mremap.c
+++ b/mm/mremap.c
@@ -25,6 +25,7 @@
 #include <linux/uaccess.h>
 #include <linux/userfaultfd_k.h>
 #include <linux/mempolicy.h>
+#include <linux/page_size_compat.h>
 
 #include <asm/cacheflush.h>
 #include <asm/tlb.h>
@@ -1063,11 +1064,11 @@ SYSCALL_DEFINE5(mremap, unsigned long, addr, unsigned long, old_len,
 		return ret;
 
 
-	if (offset_in_page(addr))
+	if (__offset_in_page_log(addr))
 		return ret;
 
-	old_len = PAGE_ALIGN(old_len);
-	new_len = PAGE_ALIGN(new_len);
+	old_len = __PAGE_ALIGN(old_len);
+	new_len = __PAGE_ALIGN(new_len);
 
 	/*
 	 * We allow a zero old-len as a special case