Add error message when elf_parser fails on long section names

Addresses: #532
solana-labs · Oct 4, 2023 · f1f0042 · f1f0042
1 parent 32b1a6f
commit f1f0042
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Showing 4 changed files with 34 additions and 2 deletions.
diff --git a/src/elf_parser/mod.rs b/src/elf_parser/mod.rs
@@ -8,7 +8,8 @@ use std::{fmt, mem, ops::Range, slice};
 use crate::{ArithmeticOverflow, ErrCheckedArithmetic};
 use {consts::*, types::*};
 
-const SECTION_NAME_LENGTH_MAXIMUM: usize = 16;
+/// Maximum length of section name allowed.
+pub const SECTION_NAME_LENGTH_MAXIMUM: usize = 16;
 const SYMBOL_NAME_LENGTH_MAXIMUM: usize = 64;
 
 /// Error definitions
@@ -26,6 +27,9 @@ pub enum ElfParserError {
     /// Section or symbol name is not UTF8 or too long
     #[error("invalid string")]
     InvalidString,
+    /// Section or symbol name is too long
+    #[error("Section/symbol name size `{0}` longer than `{1}` bytes.")]
+    InvalidStringTooLong(String, usize),
     /// An index or memory range does exeed its boundaries
     #[error("value out of bounds")]
     OutOfBounds,
@@ -396,7 +400,14 @@ impl<'a> Elf64<'a> {
             .iter()
             .position(|byte| *byte == 0x00)
             .and_then(|string_length| unterminated_string_bytes.get(0..string_length))
-            .ok_or(ElfParserError::InvalidString)
+            .ok_or_else(|| {
+                let string_bytes_unparsed =
+                    match String::from_utf8(unterminated_string_bytes.to_vec()) {
+                        Ok(x) => x,
+                        Err(_) => ElfParserError::InvalidString.to_string(),
+                    };
+                ElfParserError::InvalidStringTooLong(string_bytes_unparsed, maximum_length)
+            })
     }
 
     /// Returns the string corresponding to the given `sh_name`

diff --git a/src/elf_parser_glue.rs b/src/elf_parser_glue.rs
@@ -527,6 +527,7 @@ impl From<ElfParserError> for ElfError {
         match err {
             ElfParserError::InvalidSectionHeader
             | ElfParserError::InvalidString
+            | ElfParserError::InvalidStringTooLong(_, _)
             | ElfParserError::InvalidSize
             | ElfParserError::Overlap
             | ElfParserError::SectionNotInOrder

diff --git a/tests/elfs/long_section_name.so b/tests/elfs/long_section_name.so
diff --git a/tests/execution.rs b/tests/execution.rs
@@ -2208,6 +2208,26 @@ fn test_relative_call() {
     );
 }
 
+#[test]
+#[should_panic(
+    expected = r#"called `Result::unwrap()` on an `Err` value: ElfError(FailedToParse("Section/symbol name size `.bss.__rust_no_a` longer than `16` bytes."))"#
+)]
+fn test_long_section_name() {
+    test_interpreter_and_jit_elf!(
+        "tests/elfs/long_section_name.so",
+        [1],
+        (),
+        TestContextObject::new(18),
+        ProgramResult::Err(EbpfError::ElfError(
+            solana_rbpf::elf_parser::ElfParserError::InvalidStringTooLong(
+                ".bss.__rust_no_a".to_string(),
+                solana_rbpf::elf_parser::SECTION_NAME_LENGTH_MAXIMUM
+            )
+            .into()
+        )),
+    );
+}
+
 #[test]
 fn test_bpf_to_bpf_scratch_registers() {
     test_interpreter_and_jit_asm!(