tarantool / luajit / 13159888090

93%

Build Type

push

github

Committed by Buristan

Commit Message

Reject negative getfenv()/setfenv() levels to prevent compiler warning.

Thanks to Sergey Kaplun.

(cherry picked from commit 9d777346b)

When the number represented the level value is given to the
`getfenv()`/`setfenv()`, it is cast to the `int`. Assume the given value
is `2^31`, i.e. the resulting value after the cast is `INT_MIN`. After
this, it will be decremented in `lj_debug_level()` and underflowed to
the `INT_MAX`. That produces the UBSan warning about signed integer
overflow.

This patch raises the error early in the aforementioned functions, since
a negative level value is meaningless.

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

Part of tarantool/tarantool#11055

Reviewed-by: Sergey Bronnikov <sergeyb@tarantool.org>
Signed-off-by: Sergey Kaplun <skaplun@tarantool.org>

Run Details

5696 of 6035 branches covered (94.38%)

Branch coverage included in aggregate %.

4 of 4 new or added lines in 1 file covered. (100.0%)

13 existing lines in 4 files now uncovered.

21700 of 23442 relevant lines covered (92.57%)

2961911.21 hits per line