WM: Fix invalid memory access in wmTimer handling code. 2.93 version #105406

Bastien Montagne · 2023-03-03T16:22:18+01:00

Bastien Montagne commented

2023-03-03 16:22:18 +01:00

Timer management code often loops over the list of timers, calling
independant callbacks that end up freeing other timers in the list. That
would result in potentail access-after-free errors, as reported in #105160.

The typical identified scenario is wmTimer calling wmJob code, which
calls some of the job's callbacks (update or end e.g.), which call
WM_report, which removes and add another timer.

To address this issue on a general level, the deletion of timers is now
deferred, with the public API WM_event_remove_timer only marking the
timer for deletion, and the private new function
wm_window_delete_removed_timers effectively removing and deleting all
marked timers.

This implements design task #105369.

Pull Request #105380

Timer management code often loops over the list of timers, calling independant callbacks that end up freeing other timers in the list. That would result in potentail access-after-free errors, as reported in #105160. The typical identified scenario is wmTimer calling wmJob code, which calls some of the job's callbacks (`update` or `end` e.g.), which call `WM_report`, which removes and add another timer. To address this issue on a general level, the deletion of timers is now deferred, with the public API `WM_event_remove_timer` only marking the timer for deletion, and the private new function `wm_window_delete_removed_timers` effectively removing and deleting all marked timers. This implements design task #105369. Pull Request #105380

Bastien Montagne added this to the 2.93 LTS milestone 2023-03-03 16:22:18 +01:00

Bastien Montagne commented

2023-03-03 16:22:42 +01:00

@blender-bot build

Bastien Montagne referenced this pull request

2023-03-03 16:24:05 +01:00

Blender LTS: Maintenance Task 2.93 #88449

Bastien Montagne force-pushed F-2.93-wmtimer-fix from d9b3f30e88 to e149018cd4

2023-03-03 16:40:51 +01:00

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Bastien Montagne commented

2023-03-03 16:40:57 +01:00