Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

fix: set a larger limit for NFA when compiling regular expressions #86

Merged
merged 3 commits into from
Feb 27, 2024
Merged

fix: set a larger limit for NFA when compiling regular expressions #86

Changes from all commits
Commits
Show all changes
3 commits
Select commit Hold shift + click to select a range
4978de4
chore: provide more details about error in `get_regexp`
plusvic Feb 27, 2024
80221a0
chore: better formatting in error message
plusvic Feb 27, 2024
530d0dc
chore: set a larger limit for the NFA while compiling regular express…
plusvic Feb 27, 2024
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
19 changes: 15 additions & 4 deletions lib/src/compiler/rules.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -206,7 +206,7 @@ impl Rules {
self.rules.get(rule_id.0 as usize).unwrap()
}

/// Returns an slice with the individual rules that were compiled.
/// Returns a slice with the individual rules that were compiled.
#[inline]
pub(crate) fn rules(&self) -> &[RuleInfo] {
self.rules.as_slice()
Expand All @@ -233,8 +233,8 @@ impl Rules {
let re = types::Regexp::new(self.regexp_pool.get(regexp_id).unwrap());

let mut parser = regex_syntax::ast::parse::ParserBuilder::new()
// This the custom configuration option that turns-on support for
// the `{,n}`. This option doesn't exist in the official
// This is the custom configuration option that turns-on support
// for the `{,n}` syntax. This option doesn't exist in the official
// `regex_syntax` crate.
.empty_min_range(true)
.build();
Expand All @@ -249,7 +249,18 @@ impl Rules {

let hir = translator.translate(re.naked(), &ast).unwrap();

regex_automata::meta::Builder::new().build_from_hir(&hir).unwrap()
// Set a size limit for the NFA automata. The default limit (10MB) is
// too small for certain regexps seen in YARA rules in the wild, see:
// https://github.com/VirusTotal/yara-x/issues/85
let config = regex_automata::meta::Config::new()
.nfa_size_limit(Some(50 * 1024 * 1024));

regex_automata::meta::Builder::new()
.configure(config)
.build_from_hir(&hir)
.unwrap_or_else(|err| {
panic!("error compiling regex `{}`: {:#?}", re.as_str(), err)
})
}

/// Returns a sub-pattern by [`SubPatternId`].
Expand Down
Loading