From bfa0e1110a4685aaf4f2778d584d7fca4ccd0fa3 Mon Sep 17 00:00:00 2001
From: Feoramund <161657516+Feoramund@users.noreply.github.com>
Date: Fri, 20 Jun 2025 06:34:51 -0400
Subject: [PATCH 1/2] mem: Don't print `Buddy_Allocator.tail`

This is always a pointer past the end of the buffer given to
`buddy_allocator_init`, which could be an invalid address. Printing may
result in a segmentation violation.
---
 core/mem/allocators.odin | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/core/mem/allocators.odin b/core/mem/allocators.odin
index a5a7d9951..335cf008e 100644
--- a/core/mem/allocators.odin
+++ b/core/mem/allocators.odin
@@ -2196,7 +2196,7 @@ The buddy allocator data.
 */
 Buddy_Allocator :: struct {
 	head:      ^Buddy_Block,
-	tail:      ^Buddy_Block,
+	tail:      ^Buddy_Block `fmt:"-"`,
 	alignment: uint,
 }
 

From 4d4356e80607273c91f107c91c89c78feef22c73 Mon Sep 17 00:00:00 2001
From: Feoramund <161657516+Feoramund@users.noreply.github.com>
Date: Fri, 20 Jun 2025 06:44:44 -0400
Subject: [PATCH 2/2] mem: Guard against `Buddy_Allocator` overwriting metadata

---
 core/mem/allocators.odin | 1 +
 1 file changed, 1 insertion(+)

diff --git a/core/mem/allocators.odin b/core/mem/allocators.odin
index 335cf008e..0eacb1b65 100644
--- a/core/mem/allocators.odin
+++ b/core/mem/allocators.odin
@@ -2328,6 +2328,7 @@ buddy_allocator_alloc_bytes_non_zeroed :: proc(b: ^Buddy_Allocator, size: uint)
 		}
 		found.is_free = false
 		data := ([^]byte)(found)[b.alignment:][:size]
+		assert(cast(uintptr)raw_data(data)+cast(uintptr)size < cast(uintptr)buddy_block_next(found), "Buddy_Allocator has made an allocation which overlaps a block header.")
 		// ensure_poisoned(data)
 		// sanitizer.address_unpoison(data)
 		return data, nil