Wasn't the heartbleed issue that you could trick it into reading past the memory it had allocated? That's different to explicitly reusing memory you've allocate

Wasn't the heartbleed issue that you could trick it into reading past the memory it had allocated? That's different to explicitly reusing memory you've allocated without clearing it in between. The original claim was that rust would prevent the class of errors that caused Heartbleed. No one claimed rust would prevent you from writing a program with a different bug that just happens to exhibit similar behavior. Buffer overruns are tricker to spot than explicitly reusing a buffer. [Edit] An example of an actual buffer overrun, with no changes to pingback. C: $:/tmp # cat bleed.c #include <fcntl.h> #include <unistd.h> #include <assert.h> void pingback(char *path, char *outpath, unsigned char *buffer) { int fd; if ((fd = open(path, O_RDONLY)) == -1) assert(!"open"); if (read(fd, buffer, 256) < 1) assert(!"read"); close(fd); size_t len = buffer[0]; if ((fd = creat(outpath, 0644)) == -1) assert(!"creat"); if (write(fd, buffer, len) != len) assert(!"write"); close(fd); } int main(int argc, char **argv) { unsigned char buffer2[10]; unsigned char buffer1[10]; pingback("yourping", "yourecho", buffer1); pingback("myping", "myecho", buffer2); } $:/tmp # gcc bleed.c && ./a.out && cat yourecho myecho #i have many secrets. this is one. #i know your one. Æ+x-core:/tmp # Rust: C:\Users\ajanuary\Desktop>cat hearbleed.rs use std::old_io::File; fn pingback(path : Path, outpath : Path, buffer : &mut[u8]) { let mut fd = File::open(&path); match fd.read(buffer) { Err(what) => panic!("say {}", what), Ok(x) => if x < 1 { return; } } let len = buffer[0] as usize; let mut outfd = File::create(&outpath); match outfd.write_all(&buffer[0 .. len]) { Err(what) => panic!("say {}", what), Ok(_) => () } } fn main() { let buffer2 = &mut[0u8; 10]; let buffer1 = &mut[0u8; 10]; pingback(Path::new("yourping"), Path::new("yourecho"), buffer1); pingback(Path::new("myping"), Path::new("myecho"), buffer2); } C:\Users\ajanuary\Desktop>hearbleed.exe thread '<main>' panicked at 'assertion failed: index.end <= self.len()', C:\bot\slave\nightly-dist-rustc-win-64\build\src\libcore\slice.rs:524