Feature - Stop truncating strings in syscalls (#31030)

* Adds the feature gate stop_truncating_strings_in_syscalls.

* Removes the truncation of everything after the first NULL byte in translate_string_and_do().

programs/bpf_loader/src/syscalls/logging.rs

@@ -24,6 +24,9 @@ declare_syscall!(
             len,
             invoke_context.get_check_aligned(),
             invoke_context.get_check_size(),
+            invoke_context
+                .feature_set
+                .is_active(&stop_truncating_strings_in_syscalls::id()),
             &mut |string: &str| {
                 stable_log::program_log(&invoke_context.get_log_collector(), string);
                 Ok(0)

programs/bpf_loader/src/syscalls/mod.rs

@@ -40,7 +40,8 @@ use {
             enable_early_verification_of_account_modifications,
             error_on_syscall_bpf_function_hash_collisions, libsecp256k1_0_5_upgrade_enabled,
             limit_secp256k1_recovery_id, reject_callx_r10,
-            stop_sibling_instruction_search_at_parent, switch_to_new_elf_parser,
+            stop_sibling_instruction_search_at_parent, stop_truncating_strings_in_syscalls,
+            switch_to_new_elf_parser,
         },
         hash::{Hasher, HASH_BYTES},
         instruction::{
@@ -428,14 +429,19 @@ fn translate_string_and_do(
     len: u64,
     check_aligned: bool,
     check_size: bool,
+    stop_truncating_strings_in_syscalls: bool,
     work: &mut dyn FnMut(&str) -> Result<u64, EbpfError>,
 ) -> Result<u64, EbpfError> {
     let buf = translate_slice::<u8>(memory_mapping, addr, len, check_aligned, check_size)?;
-    let i = match buf.iter().position(|byte| *byte == 0) {
+    let msg = if stop_truncating_strings_in_syscalls {
-        Some(i) => i,
+        buf
-        None => len as usize,
+    } else {
+        let i = match buf.iter().position(|byte| *byte == 0) {
+            Some(i) => i,
+            None => len as usize,
+        };
+        buf.get(..i).ok_or(SyscallError::InvalidLength)?
     };
-    let msg = buf.get(..i).ok_or(SyscallError::InvalidLength)?;
     match from_utf8(msg) {
         Ok(message) => work(message),
         Err(err) => Err(SyscallError::InvalidString(err, msg.to_vec()).into()),
@@ -508,6 +514,9 @@ declare_syscall!(
             len,
             invoke_context.get_check_aligned(),
             invoke_context.get_check_size(),
+            invoke_context
+                .feature_set
+                .is_active(&stop_truncating_strings_in_syscalls::id()),
             &mut |string: &str| Err(SyscallError::Panic(string.to_string(), line, column).into()),
         )
     }
@@ -2046,6 +2055,7 @@ mod tests {
                 string.len() as u64,
                 true,
                 true,
+                true,
                 &mut |string: &str| {
                     assert_eq!(string, "Gaggablaghblagh!");
                     Ok(42)

sdk/src/feature_set.rs

@@ -641,10 +641,15 @@ pub mod include_loaded_accounts_data_size_in_fee_calculation {
 pub mod native_programs_consume_cu {
     solana_sdk::declare_id!("8pgXCMNXC8qyEFypuwpXyRxLXZdpM4Qo72gJ6k87A6wL");
 }
+
 pub mod simplify_writable_program_account_check {
     solana_sdk::declare_id!("5ZCcFAzJ1zsFKe1KSZa9K92jhx7gkcKj97ci2DBo1vwj");
 }
 
+pub mod stop_truncating_strings_in_syscalls {
+    solana_sdk::declare_id!("16FMCmgLzCNNz6eTwGanbyN2ZxvTBSLuQ6DZhgeMshg");
+}
+
 lazy_static! {
     /// Map of feature identifiers to user-visible description
     pub static ref FEATURE_NAMES: HashMap<Pubkey, &'static str> = [
@@ -801,6 +806,7 @@ lazy_static! {
         (include_loaded_accounts_data_size_in_fee_calculation::id(), "include transaction loaded accounts data size in base fee calculation #30657"),
         (native_programs_consume_cu::id(), "Native program should consume compute units #30620"),
         (simplify_writable_program_account_check::id(), "Simplify checks performed for writable upgradeable program accounts #30559"),
+        (stop_truncating_strings_in_syscalls::id(), "Stop truncating strings in syscalls #31029"),
         /*************** ADD NEW FEATURES HERE ***************/
     ]
     .iter()