Index out of range

[ethever]

Component

Forge

Have you ensured that all of these are up to date?

• Foundry
• Foundryup

What version of Foundry are you on?

forge 0.2.0 (5ea2c5e 2024-01-22T00:21:08.216952070Z)

What command(s) is the bug in?

forge debug --debug exploit.sol --sig "exec()"

Operating System

Linux

Describe the bug

(base) root@DESKTOP-Q664A32:~/projects/web3/exploits/dev5/contracts#  RUST_BACKTRACE=full forge debug --debug exploit.sol --sig "exec()"
[⠊] Compiling...
No files changed, compilation skipped
The application panicked (crashed).
Message:  range start index 24 out of range for slice of length 23
Location: crates/debugger/src/tui/draw.rs:280

This is a bug. Consider reporting it at https://github.com/foundry-rs/foundry

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   1: __libc_start_main<unknown>
      at ./csu/../csu/libc-start.c:308

Run with COLORBT_SHOW_HIDDEN=1 environment variable to disable frame filtering.
Aborted

[Evalir]

hi! thanks—is it possible for you to provide a repro so we can look into it?

@brockelmore is this the bug you ran into the other day?

[ethever]

hi! thanks—is it possible for you to provide a repro so we can look into it?

@brockelmore is this the bug you ran into the other day?

Yes, thank you for your attention to the bug report. I am new to foundry but I will make sure to document the reproduction steps clearly as soon as I am able to dedicate the required time to it.

It seems to be a bug in frontend UI, when I first start the debugger, and then i click the down button to navigate the debugger to the next binary code as you can see in the red rectangle

Keep going down the binary code and suddenly it will crash (something ran out of the range).

[mattsse]

@DaniPopes I don't remember who initially wrote this, so it's hard to make sense of what's going on here, but this looks very fishy:

foundry/crates/debugger/src/tui/draw.rs

Lines 239 to 241 in c6790a0

	let (start_line, end_line) = if needed_highlight > height {
	// highlighted section is more lines than we have avail
	(before.len(), before.len() + needed_highlight)

this sets the start line to the number of items in the vec, which then causes the index out of bounds

foundry/crates/debugger/src/tui/draw.rs

Line 280 in c6790a0

for line in &before[start_line..] {

unclear if the fix is as simple as just using len - 1

[ethever]

Thanks to #6886, this bug has been fixed