Bug #19543: Resizing IO::Buffer to zero bytes fails

• Status: Closed
• Assignee: -
• Target version: -
• ruby -v: ruby 3.3.0dev (2023-03-20T04:02:21Z master 7f696b8859) [x86_64-linux]
• Backport: 3.1: DONE, 3.2: DONE

[hanazuki (Kasumi Hanazuki)]

irb(main):001:0> IO::Buffer.new(1).resize(0)
/home/kasumi/.local/src/github.com/ruby/ruby/-e:1: warning: IO::Buffer is experimental and both the Ruby and C interface may change in the future!
/home/kasumi/.local/src/github.com/ruby/ruby/-e:1: [BUG] rb_sys_fail(rb_io_buffer_resize:realloc) - errno == 0
ruby 3.3.0dev (2023-03-20T04:02:21Z master 7f696b8859) [x86_64-linux]

# full trace is attached to this ticket

IO::Buffer#resize(0) will result in calling realloc(data->base, size) with size = 0 in rb_io_buffer_resize. Zero-sized realloc is deprecated in C (and will be UB in C23).

[hanazuki (Kasumi Hanazuki)]

patch https://github.com/ruby/ruby/pull/7569

[ioquatix (Samuel Williams)]

• Status changed from Open to Closed
• Backport changed from 2.7: UNKNOWN, 3.0: UNKNOWN, 3.1: UNKNOWN, 3.2: UNKNOWN to 2.7: UNKNOWN, 3.0: UNKNOWN, 3.1: UNKNOWN, 3.2: REQUIRED

Thanks for your PR, it was great. I have merged it with minor extensions to the tests.

https://github.com/ruby/ruby/commit/09295ea796900fb7b05d29e93364090e21598566

[ioquatix (Samuel Williams)]

• Backport changed from 2.7: UNKNOWN, 3.0: UNKNOWN, 3.1: UNKNOWN, 3.2: REQUIRED to 2.7: UNKNOWN, 3.0: REQUIRED, 3.1: REQUIRED, 3.2: REQUIRED

[ioquatix (Samuel Williams)]

• Backport changed from 2.7: UNKNOWN, 3.0: REQUIRED, 3.1: REQUIRED, 3.2: REQUIRED to 3.1: REQUIRED, 3.2: REQUIRED

Update backport required for 3.1 and 3.2 if possible.

[nagachika (Tomoyuki Chikanaga)]

• Backport changed from 3.1: REQUIRED, 3.2: REQUIRED to 3.1: REQUIRED, 3.2: DONE

ruby_3_2 c13757ed9ae02a2d03aea91bb852397aa920f3fd merged revision(s) 09295ea796900fb7b05d29e93364090e21598566.

[usa (Usaku NAKAMURA)]

• Backport changed from 3.1: REQUIRED, 3.2: DONE to 3.1: DONE, 3.2: DONE

ruby_3_1 e7c94d9d1d2bdbf396c489d1dc653c771f59bb92 merged revision(s) 09295ea796900fb7b05d29e93364090e21598566.