From c8c107a09e268cd89d8596166850d6118da0ea12 Mon Sep 17 00:00:00 2001
From: Daniel Pouzzner <douzzer@wolfssl.com>
Date: Tue, 18 Oct 2022 13:34:24 -0500
Subject: [PATCH] linuxkm/: fixes to deal with kernel 6.1+ show_free_areas()
 mess.

---
 linuxkm/linuxkm_memory.c  | 16 ++++++++++++++++
 linuxkm/linuxkm_wc_port.h | 24 ++++++++++++++++++++----
 linuxkm/module_hooks.c    | 13 +++++++++----
 3 files changed, 45 insertions(+), 8 deletions(-)

diff --git a/linuxkm/linuxkm_memory.c b/linuxkm/linuxkm_memory.c
index 8819bca74..a4889704c 100644
--- a/linuxkm/linuxkm_memory.c
+++ b/linuxkm/linuxkm_memory.c
@@ -305,3 +305,19 @@
         return;
     }
 #endif /* WOLFSSL_LINUXKM_SIMD_X86 && WOLFSSL_LINUXKM_SIMD_X86_IRQ_ALLOWED */
+
+#if defined(__PIE__) && (LINUX_VERSION_CODE >= KERNEL_VERSION(6, 1, 0))
+/* needed in 6.1+ because show_free_areas() static definition in mm.h calls
+ * __show_free_areas(), which isn't exported (neither was show_free_areas()).
+ */
+void my__show_free_areas(
+    unsigned int flags,
+    nodemask_t *nodemask,
+    int max_zone_idx)
+{
+    (void)flags;
+    (void)nodemask;
+    (void)max_zone_idx;
+    return;
+}
+#endif
diff --git a/linuxkm/linuxkm_wc_port.h b/linuxkm/linuxkm_wc_port.h
index a822c971f..49e17325f 100644
--- a/linuxkm/linuxkm_wc_port.h
+++ b/linuxkm/linuxkm_wc_port.h
@@ -105,6 +105,13 @@
          */
         #undef USE_SPLIT_PMD_PTLOCKS
         #define USE_SPLIT_PMD_PTLOCKS 0
+
+        #if LINUX_VERSION_CODE >= KERNEL_VERSION(6, 1, 0)
+            /* without this, static show_free_areas() mm.h brings in direct
+             * reference to unexported __show_free_areas().
+             */
+            #define __show_free_areas my__show_free_areas
+        #endif
     #endif
     #include <linux/mm.h>
     #ifndef SINGLE_THREADED
@@ -267,8 +274,13 @@
         typeof(kvfree) *kvfree;
         #endif
         typeof(is_vmalloc_addr) *is_vmalloc_addr;
-        typeof(kmem_cache_alloc_trace) *kmem_cache_alloc_trace;
-        typeof(kmalloc_order_trace) *kmalloc_order_trace;
+
+        #if LINUX_VERSION_CODE >= KERNEL_VERSION(6, 1, 0)
+            typeof(kmalloc_trace) *kmalloc_trace;
+        #else
+            typeof(kmem_cache_alloc_trace) *kmem_cache_alloc_trace;
+            typeof(kmalloc_order_trace) *kmalloc_order_trace;
+        #endif
 
         typeof(get_random_bytes) *get_random_bytes;
         #if LINUX_VERSION_CODE < KERNEL_VERSION(4, 0, 0)
@@ -402,8 +414,12 @@
         #define kvfree (wolfssl_linuxkm_get_pie_redirect_table()->kvfree)
     #endif
     #define is_vmalloc_addr (wolfssl_linuxkm_get_pie_redirect_table()->is_vmalloc_addr)
-    #define kmem_cache_alloc_trace (wolfssl_linuxkm_get_pie_redirect_table()->kmem_cache_alloc_trace)
-    #define kmalloc_order_trace (wolfssl_linuxkm_get_pie_redirect_table()->kmalloc_order_trace)
+    #if LINUX_VERSION_CODE >= KERNEL_VERSION(6, 1, 0)
+        #define kmalloc_trace (wolfssl_linuxkm_get_pie_redirect_table()->kmalloc_trace)
+    #else
+        #define kmem_cache_alloc_trace (wolfssl_linuxkm_get_pie_redirect_table()->kmem_cache_alloc_trace)
+        #define kmalloc_order_trace (wolfssl_linuxkm_get_pie_redirect_table()->kmalloc_order_trace)
+    #endif
 
     #define get_random_bytes (wolfssl_linuxkm_get_pie_redirect_table()->get_random_bytes)
     #if LINUX_VERSION_CODE < KERNEL_VERSION(4, 0, 0)
diff --git a/linuxkm/module_hooks.c b/linuxkm/module_hooks.c
index 74df63546..608d34611 100644
--- a/linuxkm/module_hooks.c
+++ b/linuxkm/module_hooks.c
@@ -394,10 +394,15 @@ static int set_up_wolfssl_linuxkm_pie_redirect_table(void) {
     wolfssl_linuxkm_pie_redirect_table.kvfree = kvfree;
 #endif
     wolfssl_linuxkm_pie_redirect_table.is_vmalloc_addr = is_vmalloc_addr;
-    wolfssl_linuxkm_pie_redirect_table.kmem_cache_alloc_trace =
-        kmem_cache_alloc_trace;
-    wolfssl_linuxkm_pie_redirect_table.kmalloc_order_trace =
-        kmalloc_order_trace;
+    #if LINUX_VERSION_CODE >= KERNEL_VERSION(6, 1, 0)
+        wolfssl_linuxkm_pie_redirect_table.kmalloc_trace =
+            kmalloc_trace;
+    #else
+        wolfssl_linuxkm_pie_redirect_table.kmem_cache_alloc_trace =
+            kmem_cache_alloc_trace;
+        wolfssl_linuxkm_pie_redirect_table.kmalloc_order_trace =
+            kmalloc_order_trace;
+    #endif
 
     wolfssl_linuxkm_pie_redirect_table.get_random_bytes = get_random_bytes;
     #if LINUX_VERSION_CODE < KERNEL_VERSION(4, 0, 0)