Add support for `tss_t` thread local objects in Objects.qll
Nobody has claimed this yet.
Assessment
- Difficulty
- 5/5
- Estimated time
- Over a week
- Newbie friendliness
- 25/100
Research direction
Start in Objects.qll by reading the existing storage-duration and ObjectIdentity support, then inspect how malloc, tss_create(), and tss_get() are modeled. Compare the proposed Locatable refactor with the alternative tss_t object design. Done means tss_t variables expose both the key-holding object and the thread-local object identity without breaking existing object handling.
Written by the indexing model from the issue text.
Description
Objects.qll has support for identifying objects with different storage durations (static, thread local, allocated, and automatic). However, its thread local object support is limited to _Thread_local variables.
Ideally, a tss_t variable would be recognizable as two objects:
- One object representing the variable holding the tss_t key. Usually this is an object with static lifetime.
- Another object identity for the thread local behind the
tss_t.
Unfortunately, tss_t currently extends Element, which means that it can't have two implementations of the ObjectIdentity class. Alternatively, calls to tss_get() could be considered ObjectIdentitys, however, that doesn't match the intention of the ObjectIdentity class/library, as the threadlocal is really identified by the tss_t.
The threadlocal object could be identified by the tss_create call (similarly to how we identify dynamic memory via malloc calls). But it probably makes more sense to have ObjectIdentity extend Locatable and then have a tss_t variable produce two ObjectIdentys.
Otherwise the tss_t object class will closely match the malloc object class, since malloc returns a pointer to the dynamic memory just like tss_get() returns a pointer to the thread local. Additional refactoring to share code here will be required.
- Dominant language
- CodeQL
- Stars
- 227
- Forks
- 82
- Avg merge
- 6d 7h
- Merged PRs (30d)
- 9
Contributor guide
First steps
- Read the whole issue, then the project's contributing guide.
- Comment on the issue to say you are picking it up — it saves two people doing the same work.
- Fork the repository and make your change on a branch.
- Open a pull request that references the issue number.
More from github/codeql-coding-standards
-
false positive/false negative Stardard-MISRA-C++
Difficulty 2/5 1-3 hours Newbie friendliness 72/100
github/codeql-coding-standards#1172 ·
-
Difficulty-Low false positive/false negative false-negative Impact-Low Standard-MISRA-C
Difficulty 2/5 1-3 hours Newbie friendliness 68/100
-
Difficulty-Medium false positive/false negative false-positive Impact-Medium Standard-CERT-C
Difficulty 4/5 3-5 days Newbie friendliness 48/100
github/codeql-coding-standards#1200 ·
-
`RULE-0-0-1`: "unreachable statement" false positives due to over-pruning of the control-flow graph Openfalse positive/false negative
Difficulty 4/5 3-5 days Newbie friendliness 48/100
github/codeql-coding-standards#1190 ·
-
false positive/false negative
Difficulty 3/5 1-2 days Newbie friendliness 65/100
github/codeql-coding-standards#1175 ·
All issues in github/codeql-coding-standards
Similar issues
-
Difficulty 2/5 1-3 hours Newbie friendliness 78/100
ScoopInstaller/Nonportable#639 ·
-
Difficulty 2/5 1-3 hours Newbie friendliness 68/100
ScoopInstaller/Extras#18800 ·
-
Difficulty 1/5 Under an hour Newbie friendliness 85/100
uqbar-project/website-wollok-ts#84 · 2 comments ·
-
on hold T: core-bug
Difficulty 2/5 1-3 hours Newbie friendliness 68/100
-
Difficulty 1/5 Under an hour Newbie friendliness 88/100