From 84ac59da1274568c23c6fa43be32197944b4962e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Rapha=C3=ABl=20Cauderlier?=
 <raphael.cauderlier@nomadic-labs.com>
Date: Mon, 22 Jul 2024 12:20:10 +0200
Subject: [PATCH 1/2] Kernel SDK/Mockup: fix #7378

This commit prevents the mocked implementation of the reveal_metadata
host function from panicking when its max_bytes argument is too large.
---
 src/kernel_sdk/mock/src/host.rs | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/src/kernel_sdk/mock/src/host.rs b/src/kernel_sdk/mock/src/host.rs
index 6104c15f1ad2..56b0f9f2cf29 100644
--- a/src/kernel_sdk/mock/src/host.rs
+++ b/src/kernel_sdk/mock/src/host.rs
@@ -220,15 +220,13 @@ unsafe impl SmartRollupCore for MockHost {
         self.state.borrow().store.store_value_size(path, path_len)
     }
 
-    // TODO adapt reveal_metadata
-    // https://gitlab.com/tezos/tezos/-/issues/7378
     unsafe fn reveal_metadata(&self, destination_addr: *mut u8, max_bytes: usize) -> i32 {
-        assert!(METADATA_SIZE <= max_bytes);
         let metadata: [u8; METADATA_SIZE] =
             self.state.borrow().get_metadata().clone().into();
-        let slice = from_raw_parts_mut(destination_addr, metadata.len());
-        slice.copy_from_slice(metadata.as_slice());
-        metadata.len().try_into().unwrap()
+        let len = min(max_bytes, metadata.len());
+        let slice = from_raw_parts_mut(destination_addr, len);
+        slice.copy_from_slice(&metadata[..len]);
+        len as i32
     }
 
     // TODO turn payload.split_at into a read or error code helper function.
-- 
GitLab


From 0b93cd4de9648cbe7f2bcbf7f3362bfdbf6c63ce Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Rapha=C3=ABl=20Cauderlier?=
 <raphael.cauderlier@nomadic-labs.com>
Date: Mon, 22 Jul 2024 12:40:18 +0200
Subject: [PATCH 2/2] Kernel SDK/Mockup: fix #7377

When the lenght of the payload given to the mocked reveal host
function is too short, the mocked reveal host function now returns 0
instead of panicking.
---
 src/kernel_sdk/mock/src/host.rs | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/src/kernel_sdk/mock/src/host.rs b/src/kernel_sdk/mock/src/host.rs
index 56b0f9f2cf29..9b74b49d3fd9 100644
--- a/src/kernel_sdk/mock/src/host.rs
+++ b/src/kernel_sdk/mock/src/host.rs
@@ -229,8 +229,6 @@ unsafe impl SmartRollupCore for MockHost {
         len as i32
     }
 
-    // TODO turn payload.split_at into a read or error code helper function.
-    // https://gitlab.com/tezos/tezos/-/issues/7377
     unsafe fn reveal(
         &self,
         payload_addr: *const u8,
@@ -239,6 +237,9 @@ unsafe impl SmartRollupCore for MockHost {
         max_bytes: usize,
     ) -> i32 {
         let payload: &[u8] = from_raw_parts(payload_addr, payload_len);
+        if payload.is_empty() {
+            return 0;
+        }
         let (tag, payload) = payload.split_at(size_of::<u8>());
         match tag[0] {
             0 => {
@@ -256,6 +257,13 @@ unsafe impl SmartRollupCore for MockHost {
             }
             2 => {
                 // Reveal_dal_page
+
+                const PAYLOAD_SIZE: usize =
+                    size_of::<i32>() + size_of::<u8>() + size_of::<i16>();
+                if payload.len() < PAYLOAD_SIZE {
+                    return 0;
+                }
+
                 let (published_level, remaining) = payload.split_at(size_of::<i32>());
                 let (slot_index, remaining) = remaining.split_at(size_of::<u8>());
                 let (page_index, _) = remaining.split_at(size_of::<i16>());
-- 
GitLab