30 lines
605 B
Rust
30 lines
605 B
Rust
fn demo_mut_advanced_unique(mut our: Box<i32>) -> i32 {
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unknown_code_1(&*our);
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// This "re-asserts" uniqueness of the reference: After writing, we know
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// our tag is at the top of the stack.
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*our = 5;
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unknown_code_2();
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// We know this will return 5
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*our //~ ERROR does not exist on the stack
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}
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// Now comes the evil context
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use std::ptr;
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static mut LEAK: *mut i32 = ptr::null_mut();
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fn unknown_code_1(x: &i32) { unsafe {
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LEAK = x as *const _ as *mut _;
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} }
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fn unknown_code_2() { unsafe {
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*LEAK = 7;
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} }
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fn main() {
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assert_eq!(demo_mut_advanced_unique(Box::new(0)), 5);
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}
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