From 098dba607ace19fb5dcb5bddc12823b0bb4777f6 Mon Sep 17 00:00:00 2001
From: Michael Vines <mvines@gmail.com>
Date: Tue, 30 Nov 2021 10:41:15 -0800
Subject: [PATCH] Fix more BPF alignment issues on arm64

---
 programs/bpf_loader/src/serialization.rs | 19 ++++++++-----------
 programs/bpf_loader/src/syscalls.rs      |  4 ++--
 sdk/program/src/entrypoint.rs            |  6 +++---
 3 files changed, 13 insertions(+), 16 deletions(-)

diff --git a/programs/bpf_loader/src/serialization.rs b/programs/bpf_loader/src/serialization.rs
index d9aeae6302..86cb5b9844 100644
--- a/programs/bpf_loader/src/serialization.rs
+++ b/programs/bpf_loader/src/serialization.rs
@@ -3,16 +3,13 @@ use solana_rbpf::{aligned_memory::AlignedMemory, ebpf::HOST_ALIGN};
 use solana_sdk::{
     account::{ReadableAccount, WritableAccount},
     bpf_loader_deprecated,
-    entrypoint::{MAX_PERMITTED_DATA_INCREASE, PARAMETER_ALIGNMENT},
+    entrypoint::{BPF_ALIGN_OF_U128, MAX_PERMITTED_DATA_INCREASE},
     instruction::InstructionError,
     keyed_account::KeyedAccount,
     pubkey::Pubkey,
     system_instruction::MAX_PERMITTED_DATA_LENGTH,
 };
-use std::{
-    io::prelude::*,
-    mem::{align_of, size_of},
-};
+use std::{io::prelude::*, mem::size_of};
 
 /// Look for a duplicate account and return its position if found
 pub fn is_dup(accounts: &[KeyedAccount], keyed_account: &KeyedAccount) -> (bool, usize) {
@@ -183,7 +180,7 @@ pub fn get_serialized_account_size_aligned(
             + size_of::<u64>()  // data len
             + data_len
             + MAX_PERMITTED_DATA_INCREASE
-            + (data_len as *const u8).align_offset(align_of::<u128>())
+            + (data_len as *const u8).align_offset(BPF_ALIGN_OF_U128)
             + size_of::<u64>(), // rent epoch
     )
 }
@@ -242,7 +239,7 @@ pub fn serialize_parameters_aligned(
                 .map_err(|_| InstructionError::InvalidArgument)?;
             v.resize(
                 MAX_PERMITTED_DATA_INCREASE
-                    + (v.write_index() as *const u8).align_offset(PARAMETER_ALIGNMENT),
+                    + (v.write_index() as *const u8).align_offset(BPF_ALIGN_OF_U128),
                 0,
             )
             .map_err(|_| InstructionError::InvalidArgument)?;
@@ -306,7 +303,7 @@ pub fn deserialize_parameters_aligned(
             };
             account.set_data_from_slice(&buffer[start..data_end]);
             start += *pre_len + MAX_PERMITTED_DATA_INCREASE; // data
-            start += (start as *const u8).align_offset(align_of::<u128>());
+            start += (start as *const u8).align_offset(BPF_ALIGN_OF_U128);
             start += size_of::<u64>(); // rent_epoch
         }
     }
@@ -478,7 +475,7 @@ mod tests {
         assert_eq!(&program_id, de_program_id);
         assert_eq!(instruction_data, de_instruction_data);
         assert_eq!(
-            (&de_instruction_data[0] as *const u8).align_offset(align_of::<u128>()),
+            (&de_instruction_data[0] as *const u8).align_offset(BPF_ALIGN_OF_U128),
             0
         );
         for ((_, _, key, account), account_info) in keyed_accounts.iter().skip(1).zip(de_accounts) {
@@ -491,7 +488,7 @@ mod tests {
             assert_eq!(account.rent_epoch(), account_info.rent_epoch);
 
             assert_eq!(
-                (*account_info.lamports.borrow() as *const u64).align_offset(align_of::<u64>()),
+                (*account_info.lamports.borrow() as *const u64).align_offset(BPF_ALIGN_OF_U128),
                 0
             );
             assert_eq!(
@@ -499,7 +496,7 @@ mod tests {
                     .data
                     .borrow()
                     .as_ptr()
-                    .align_offset(align_of::<u128>()),
+                    .align_offset(BPF_ALIGN_OF_U128),
                 0
             );
         }
diff --git a/programs/bpf_loader/src/syscalls.rs b/programs/bpf_loader/src/syscalls.rs
index d05ba9732a..33c63f04f1 100644
--- a/programs/bpf_loader/src/syscalls.rs
+++ b/programs/bpf_loader/src/syscalls.rs
@@ -22,7 +22,7 @@ use solana_sdk::{
     account_info::AccountInfo,
     blake3, bpf_loader, bpf_loader_deprecated, bpf_loader_upgradeable,
     clock::Clock,
-    entrypoint::{MAX_PERMITTED_DATA_INCREASE, SUCCESS},
+    entrypoint::{BPF_ALIGN_OF_U128, MAX_PERMITTED_DATA_INCREASE, SUCCESS},
     epoch_schedule::EpochSchedule,
     feature_set::{
         blake3_syscall_enabled, demote_program_write_locks, disable_fees_sysvar,
@@ -747,7 +747,7 @@ impl SyscallObject<BpfError> for SyscallAllocFree {
         result: &mut Result<u64, EbpfError<BpfError>>,
     ) {
         let align = if self.aligned {
-            align_of::<u128>()
+            BPF_ALIGN_OF_U128
         } else {
             align_of::<u8>()
         };
diff --git a/sdk/program/src/entrypoint.rs b/sdk/program/src/entrypoint.rs
index 317f0665fe..6442ac9246 100644
--- a/sdk/program/src/entrypoint.rs
+++ b/sdk/program/src/entrypoint.rs
@@ -252,8 +252,8 @@ unsafe impl std::alloc::GlobalAlloc for BumpAllocator {
 /// Maximum number of bytes a program may add to an account during a single realloc
 pub const MAX_PERMITTED_DATA_INCREASE: usize = 1_024 * 10;
 
-// Parameters passed to the entrypoint input buffer are aligned on 8-byte boundaries
-pub const PARAMETER_ALIGNMENT: usize = 8;
+/// `assert_eq(std::mem::align_of::<u128>(), 8)` is true for BPF but not for some host machines
+pub const BPF_ALIGN_OF_U128: usize = 8;
 
 /// Deserialize the input arguments
 ///
@@ -312,7 +312,7 @@ pub unsafe fn deserialize<'a>(input: *mut u8) -> (&'a Pubkey, Vec<AccountInfo<'a
                 from_raw_parts_mut(input.add(offset), data_len)
             }));
             offset += data_len + MAX_PERMITTED_DATA_INCREASE;
-            offset += (offset as *const u8).align_offset(PARAMETER_ALIGNMENT); // padding
+            offset += (offset as *const u8).align_offset(BPF_ALIGN_OF_U128); // padding
 
             #[allow(clippy::cast_ptr_alignment)]
             let rent_epoch = *(input.add(offset) as *const u64);