Bug 1685194

Summary:	Assertion retrieving CKA_ID that has been explicitiy created as zero-length byte string
Product:	[Fedora] Fedora	Reporter:	space88man <shihping.chan>
Component:	softhsm	Assignee:	Paul Wouters <pwouters>
Status:	CLOSED EOL	QA Contact:	Fedora Extras Quality Assurance <extras-qa>
Severity:	unspecified	Docs Contact:
Priority:	unspecified
Version:	29	CC:	nmavrogi, pwouters
Target Milestone:	---
Target Release:	---
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:
Fixed In Version:		Doc Type:	If docs needed, set a value
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2019-11-27 21:20:29 UTC	Type:	Bug
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description space88man 2019-03-04 15:24:23 UTC

Description of problem:
Create a private key with out CKA_ID explicitly set to zero-length byte string in the template.

Trying  to retrieve the attribute results in the assertion

/usr/include/c++/8/bits/stl_vector.h:950: std::vector<_Tp, _Alloc>::const_reference std::vector<_Tp, _Alloc>::operator[](std::vector<_Tp, _Alloc>::size_type) const [with _Tp = unsigned char; _Alloc = SecureAllocator<unsigned char>; std::vector<_Tp, _Alloc>::const_reference = const unsigned char&; std::vector<_Tp, _Alloc>::size_type = long unsigned int]: Assertion '__builtin_expect(__n <
this->size(), true)' failed.



Version-Release number of selected component (if applicable):


How reproducible:
softhsm-2.5.0-2.fc29.x86_64


Steps to Reproduce:
1. Create private key and explicitly set CKA_ID to zero-length byte string
2. Reproducers in the external ticket
3. C_GetAttributeValue on CKA_ID

Actual results:

/usr/include/c++/8/bits/stl_vector.h:950: std::vector<_Tp, _Alloc>::const_reference std::vector<_Tp, _Alloc>::operator[](std::vector<_Tp, _Alloc>::size_type) const [with _Tp = unsigned char; _Alloc = SecureAllocator<unsigned char>; std::vector<_Tp, _Alloc>::const_reference = const unsigned char&; std::vector<_Tp, _Alloc>::size_type = long unsigned int]: Assertion '__builtin_expect(__n < this->size(), true)' failed.
Aborted (core dumped)


Expected results:
Able to retrieve the zero-length CKA_ID


Additional info:
1. For public key and certs, there is no issue in retrieving CKA_ID even if explicitly created as zero-length byte string
2. For new private keys without explicit CKA_ID in the template; there is an implicit zero-length CKA_ID and this can be retrieved. But once the CKA_ID is explicitly set, then the error occurs

Comment 1 space88man 2019-03-04 15:30:41 UTC

Problem does not happen on CentOS 7/RHEL 7 with softhsm-2.1.0-2.el7.x86_64

Comment 2 space88man 2019-03-04 15:47:30 UTC

Build from upstream Github develop/2.5.0 with no Fedora localisations

sh autogen.sh
./configure --disable-strict
make

The resulting artifacts works without assertion

Comment 3 space88man 2019-03-05 03:01:23 UTC

TL;DR - taking a reference of the "first" element of a zero-length unsigned char array

Root cause:
when retrieving attributes from sensitive objects(e.g. private keys), the serialized attribute value is first decrypted, but P11Attributes.cpp:343 does not check the return value has size != 0. It takes a reference, &byteString[0], on a zero-length array.

When the library is built with -Wp,-D_GLIBCXX_ASSERTIONS the assertion is triggered.

Comment 4 Ben Cotton 2019-10-31 19:51:53 UTC

This message is a reminder that Fedora 29 is nearing its end of life.
Fedora will stop maintaining and issuing updates for Fedora 29 on 2019-11-26.
It is Fedora's policy to close all bug reports from releases that are no longer
maintained. At that time this bug will be closed as EOL if it remains open with a
Fedora 'version' of '29'.

Package Maintainer: If you wish for this bug to remain open because you
plan to fix it in a currently maintained version, simply change the 'version' 
to a later Fedora version.

Thank you for reporting this issue and we are sorry that we were not 
able to fix it before Fedora 29 is end of life. If you would still like 
to see this bug fixed and are able to reproduce it against a later version 
of Fedora, you are encouraged  change the 'version' to a later Fedora 
version prior this bug is closed as described in the policy above.

Although we aim to fix as many bugs as possible during every release's 
lifetime, sometimes those efforts are overtaken by events. Often a 
more recent Fedora release includes newer upstream software that fixes 
bugs or makes them obsolete.

Comment 5 Ben Cotton 2019-11-27 21:20:29 UTC

Fedora 29 changed to end-of-life (EOL) status on 2019-11-26. Fedora 29 is
no longer maintained, which means that it will not receive any further
security or bug fix updates. As a result we are closing this bug.

If you can reproduce this bug against a currently maintained version of
Fedora please feel free to reopen this bug against that version. If you
are unable to reopen this bug, please file a new report against the
current release. If you experience problems, please add a comment to this
bug.

Thank you for reporting this bug and we are sorry it could not be fixed.