Bug #20239: Segmentation fault when using Regex on a large String

• Status: Closed
• Assignee: -
• Target version: -
• ruby -v: ruby 3.3.0 (2023-12-25 revision 5124f9ac75) [aarch64-linux]
• Backport: 3.0: UNKNOWN, 3.1: UNKNOWN, 3.2: UNKNOWN, 3.3: UNKNOWN

[martinsp (Martins Polakovs)]

Since v3.2.0 ruby crashes with segmentation fault on the following script with a [BUG] Segmentation fault at ...

require "rbconfig/sizeof"
("\u{0101}" + "a" * RbConfig::LIMITS["INT_MAX"] + "b").match(/b/)

Crash can be reproduced on the following ruby versions:

• ruby 3.2.0 (2022-12-25 revision a528908271) [aarch64-linux]
• ruby 3.2.3 (2024-01-18 revision 52bb2ac0a6) [aarch64-linux]
• ruby 3.3.0 (2023-12-25 revision 5124f9ac75) [aarch64-linux]

ruby 3.1.4p223 (2023-03-30 revision 957bb7cb81) [aarch64-linux] works as expected

It seems that call to enclen inside str_lower_case_match returns negative offset in this case https://bugs.ruby-lang.org/projects/ruby-master/repository/git/revisions/v3_3_0/entry/regexec.c#L4180

[nobu (Nobuyoshi Nakada)]

• Status changed from Open to Closed

Applied in changeset git|75aaeb35b82da26359b9418d2963384d0c55839c.

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[Bug #20239] Fix overflow at down-casting