aboutsummaryrefslogtreecommitdiffhomepage
path: root/src
diff options
context:
space:
mode:
authorJohannes Stoelp <johannes.stoelp@gmail.com>2023-10-22 14:24:33 +0200
committerJohannes Stoelp <johannes.stoelp@gmail.com>2023-10-22 14:24:33 +0200
commit474c2545cbb1af85a326a47e202fe1e6c450b496 (patch)
tree51a0850b590f4cdcea526a2dba9d1bfc41aeb961 /src
parent47a16f36313273a2e3b40440d71b264e35463c05 (diff)
downloadjuicebox-asm-474c2545cbb1af85a326a47e202fe1e6c450b496.tar.gz
juicebox-asm-474c2545cbb1af85a326a47e202fe1e6c450b496.zip
Remove write permissions from runtime code buffer after copying jitted code
Diffstat (limited to 'src')
-rw-r--r--src/rt.rs9
1 files changed, 7 insertions, 2 deletions
diff --git a/src/rt.rs b/src/rt.rs
index 7b5f74b..20d1de7 100644
--- a/src/rt.rs
+++ b/src/rt.rs
@@ -1,7 +1,7 @@
//! A simple runtime which can be used to execute emitted instructions.
use core::ffi::c_void;
-use nix::sys::mman::{mmap, munmap, MapFlags, ProtFlags};
+use nix::sys::mman::{mmap, mprotect, munmap, MapFlags, ProtFlags};
/// A simple `mmap`ed runtime with executable pages.
pub struct Runtime {
@@ -18,7 +18,7 @@ impl Runtime {
mmap(
None,
len,
- ProtFlags::PROT_WRITE | ProtFlags::PROT_READ | ProtFlags::PROT_EXEC,
+ ProtFlags::PROT_WRITE,
MapFlags::MAP_PRIVATE | MapFlags::MAP_ANONYMOUS,
0, /* fd */
0, /* off */
@@ -31,6 +31,11 @@ impl Runtime {
assert!(code.len() < len.get());
unsafe { std::ptr::copy_nonoverlapping(code.as_ptr(), buf.cast(), len.get()) };
}
+ unsafe {
+ // Remove write permissions from code buffer and allow to read-execute from it.
+ mprotect(buf, len.get(), ProtFlags::PROT_READ | ProtFlags::PROT_EXEC)
+ .expect("Failed to RX mprotect Runtime code buffer");
+ }
Runtime {
buf,