tarantool / luajit / 8555119233

93%

tarantool/master: 93%

Build Type

push

github

Committed by Buristan

Commit Message

Correct fix for stack check when recording BC_VARG.

Reported by Yichun Zhang.

(cherry picked from commit b2791179e)

This patch is a follow-up for the commit
5f0a43ace ("bugfix: fixed assertion
failure "lj_record.c:92: rec_check_slots: Assertion `nslots <= 250'
failed" found by stressing our edgelang compiler."), which is identical
to the commit e0388e6c0 ("Fix stack check
when recording BC_VARG.)" from the upstream. The error is raised too
late, when buffer overflow of `J->slot` has already occurred and data in
the `jit_State` structure is corrupted.

This patch moves the corresponding check before using the `J->slot`
buffer. The `J->maxslot` may overflow the buffer only in cases where the
amount of the vararg results is unknown. The check is used only in this
case since the trace recording for the undefined-on-trace varargs is not
yet implemented for an unknown amount of varargs.

Sergey Kaplun:
* added the description and the test for the problem

Part of tarantool/tarantool#9595

Coverage Stats

5660 of 6018 branches covered (94.05%)

Branch coverage included in aggregate %.

2 of 2 new or added lines in 1 file covered. (100.0%)

4 existing lines in 3 files now uncovered.

21600 of 23417 relevant lines covered (92.24%)

2923283.55 hits per line