Fix: Reachable assertion (radix is to high)

[nyw0102]

platform: Linux

version: Latest

Overview:

Reachable assertion code in core::char::to_digit:L349 caused by input “777_77” in REPL.

Error Message
"thread 'main' panicked at 'to_digit: radix is too high (maximum 36)", /home/nyw0102/s2fuzz/scripts/rust/library/core/src/char/methods.rs:349:13`

ASAN log (SEGV)

`AddressSanitizer:DEADLYSIGNAL

==1969104==ERROR: AddressSanitizer: SEGV on unknown address 0x100080006c6e (pc 0x55555573da2f bp 0x7ffffffea830 sp 0x7ffffffe9fe0 T0)
==1969104==The signal is caused by a READ memory access.
#0 0x55555573da2f (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x1e9a2f) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#1 0x555557ed135a (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x297d35a) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#2 0x155555348d3f (/lib/x86_64-linux-gnu/libc.so.6+0x174d3f) (BuildId: 962015aa9d133c6cbcfb31ec300596d7f44d3348)
#3 0x555557ee61a0 (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x29921a0) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#4 0x555557eca3d3 (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x29763d3) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#5 0x555557ed1310 (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x297d310) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#6 0x1555554fb5b3 (/lib/x86_64-linux-gnu/libgcc_s.so.1+0x175b3) (BuildId: e3a44e0da9c6e835d293ed8fd2882b4c4a87130c)
#7 0x555557ee53de (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x29913de) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#8 0x555557f0161b (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x29ad61b) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#9 0x555557ed0d74 (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x297cd74) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#10 0x555557ed6f43 (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x2982f43) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#11 0x555557ed6b83 (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x2982b83) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#12 0x555557ed7522 (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x2983522) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#13 0x555557ee5878 (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x2991878) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#14 0x555557ee5513 (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x2991513) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#15 0x555557ed7211 (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x2983211) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#16 0x5555556e7502 (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x193502) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#17 0x555557551bf9 (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x1ffdbf9) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#18 0x555557c4d502 (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x26f9502) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#19 0x555557ae6513 (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x2592513) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#20 0x555557ad0dbc (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x257cdbc) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#21 0x555557acdcc0 (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x2579cc0) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#22 0x555557aca33a (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x257633a) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#23 0x555557ac71d2 (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x25731d2) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#24 0x555557ac4226 (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x2570226) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#25 0x555557ac1e71 (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x256de71) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#26 0x555557abb0a1 (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x25670a1) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#27 0x555557ab7b90 (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x2563b90) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#28 0x555557ab4f30 (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x2560f30) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#29 0x555557aa75c0 (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x25535c0) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#30 0x555557aa3ce6 (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x254fce6) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#31 0x555557aa0dc6 (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x254cdc6) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#32 0x555557a9a8a5 (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x25468a5) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#33 0x555557a8f55c (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x253b55c) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#34 0x555557a8d54f (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x253954f) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#35 0x555557a897a4 (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x25357a4) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#36 0x5555558f630d (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x3a230d) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#37 0x5555558ffbf0 (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x3abbf0) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#38 0x5555558fe23d (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x3aa23d) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#39 0x555555913381 (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x3bf381) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#40 0x555555ad1252 (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x57d252) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#41 0x55555590f46d (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x3bb46d) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#42 0x5555557e29fa (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x28e9fa) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#43 0x5555557cb3da (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x2773da) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#44 0x5555557cf616 (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x27b616) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#45 0x555557ecff94 (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x297bf94) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#46 0x5555557cf238 (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x27b238) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#47 0x555555918c2f (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x3c4c2f) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
#48 0x1555551fdd8f (/lib/x86_64-linux-gnu/libc.so.6+0x29d8f) (BuildId: 962015aa9d133c6cbcfb31ec300596d7f44d3348)
#49 0x1555551fde3f (/lib/x86_64-linux-gnu/libc.so.6+0x29e3f) (BuildId: 962015aa9d133c6cbcfb31ec300596d7f44d3348)
#50 0x5555556f26b4 (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x19e6b4) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)

AddressSanitizer can not provide additional info.
SUMMARY: AddressSanitizer: SEGV (/home/nyw0102/Test-Sets/kalker/target/x86_64-unknown-linux-gnu/debug/kalker+0x1e9a2f) (BuildId: 0e98ee328013dbca462706015cb56f4bb56e0f94)
==1969104==ABORTING`

Description

First, input “777_77” goes into function “string_to_num” via parameter named “value”
fn string_to_num(value: &str) -> Result<f64, KalkError> { let base = get_base(value)?; if let Some(result) = crate::radix::parse_float_radix(&value.replace(" ", ""), base) { Ok(result) } else { Err(KalkError::InvalidNumberLiteral(value.into())) } }
In this function, the “base” value is initialized by function get_base with parameter “value” which is “777_77”
`fn get_base(value: &str) -> Result<u8, KalkError> {
let underscore_pos = if let Some(i) = value.find('_') {
i
} else {
return Ok(10);
};

let subscript = value.chars().skip(underscore_pos + 1usize);
if let Some(base) = crate::text_utils::parse_subscript(subscript) {
    Ok(base)
} else {
    Err(KalkError::UnrecognizedBase)
}

}`

In “get_base(value: &str) function, it erases all letters before “_” in string “777_77” and produces an iterator with value “77”. And this returns the value from function “kalker::text_utils::parse_subscript” which is initialized the iterator.
pub fn parse_subscript(chars: impl Iterator<Item = char>) -> Option<u8> { if let Ok(result) = subscript_to_normal(chars).parse::<u8>() { Some(result) } else { None } }

This function returns a value from kalker::text_utils::subscript_to_normal function initiated with “chars”

`pub fn subscript_to_normal(chars: impl Iterator<Item = char>) -> String {
let mut regular = String::new();
for c in chars {
regular.push(match c {
'₀' => '0',
'₁' => '1',
'₂' => '2',
'₃' => '3',
'₄' => '4',
'₅' => '5',
'₆' => '6',
'₇' => '7',
'₈' => '8',
'₉' => '9',
'₊' => '+',
'₋' => '-',
'₌' => '=',
'₍' => '(',
'₎' => ')',
'ₖ' => 'k',
'ₗ' => 'l',
'ₘ' => 'm',
'ₙ' => 'n',
'ᵀ' => 'T',
_ => c,
});
}

return regular.trim().to_string();

}
`

This function matches each letter in “chars” by iteration. So, this function finally return the value Ok(”77”)
After this process, the “string_to_num” function initialize the value “base” as “Ok(”77”)
Then, this “base’ flows into function “parse_float_radix” as parameter named “base”.

`pub fn parse_float_radix(value: &str, radix: u8) -> Option {
if radix == 10 {
return if let Ok(result) = value.parse::() {
Some(result)
} else {
None
};
}

let mut sum = 0f64;
let length = value.find('_').unwrap_or(value.len());
let mut i = (value.find('.').unwrap_or(length) as i32) - 1;
for c in value.chars() {
    if c == '_' {
        break;
    }

    if c == '.' {
        continue;
    }

    let digit = c.to_digit(radix as u32)? as f64;
    sum += digit * (radix as f64).powi(i as i32);
    i -= 1;
}

Some(sum)

}This function calls to_digit() function with parameter “77”pub const fn to_digit(self, radix: u32) -> Option {
// If not a digit, a number greater than radix will be created.
let mut digit = (self as u32).wrapping_sub('0' as u32);
if radix > 10 {
assert!(radix <= 36, "to_digit: radix is too high (maximum 36)");
if digit < 10 {
return Some(digit);
}
// Force the 6th bit to be set to ensure ascii is lower case.
digit = (self as u32 | 0b10_0000).wrapping_sub('a' as u32).saturating_add(10);
}
// FIXME: once then_some is const fn, use it here
if digit < radix { Some(digit) } else { None }
}`
And finally to_digit() function gets value “77” as ‘radix’ parameter get it encounters assert!(radix <= 36, "to_digit: radix is too high (maximum 36)")

How to Reproduce

1. Run ‘kalker’ with command “./kalker -p 3 -a deg”.
2. In the started repl, insert “777_77”

[PaddiM8]

Thanks!