winmm: Fix use-after-free race between stream destroy and buffer thread. - #854
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Destroy could free a stream while buffer thread work items referencing it were still queued or in flight, particularly after a data callback error. Count pending work items per stream (and in-flight driver callbacks per context) and make destroy wait for them to drain. Also fix free_buffers accounting on refill's error paths so the wait terminates.
padenot
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Aug 14, 2026
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… and WinMM stream destroy fixes. a=RyanVM This branch pins an older libcubeb revision, so the two fixes are carried as local vendoring patches rather than a full libcubeb update: - wasapi-output-mix-channel-count.patch: upstream cubeb dc56ea41 and f0bd97db (mozilla/cubeb#856), bug 2061220. Creates the output mixer when the device mix channel count differs from the stream channel count, and rejects stream params whose layout and channel count disagree. - winmm-destroy-work-item-uaf.patch: upstream cubeb f6b59a3b (mozilla/cubeb#854), bug 2058051. Counts pending buffer thread work items per stream and in-flight driver callbacks per context so stream and context destruction wait for them to drain. Differential Revision: https://phabricator.services.mozilla.com/D319944
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… and WinMM stream destroy fixes. a=RyanVM DONTBUILD This branch pins an older libcubeb revision, so the two fixes are carried as local vendoring patches rather than a full libcubeb update: - wasapi-output-mix-channel-count.patch: upstream cubeb dc56ea41 and f0bd97db (mozilla/cubeb#856), bug 2061220. Creates the output mixer when the device mix channel count differs from the stream channel count, and rejects stream params whose layout and channel count disagree. - winmm-destroy-work-item-uaf.patch: upstream cubeb f6b59a3b (mozilla/cubeb#854), bug 2058051. Counts pending buffer thread work items per stream and in-flight driver callbacks per context so stream and context destruction wait for them to drain. Differential Revision: https://phabricator.services.mozilla.com/D319945
lando-worker Bot
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Aug 20, 2026
… and WinMM stream destroy fixes. a=RyanVM DONTBUILD This branch pins an older libcubeb revision, so the two fixes are carried as local vendoring patches rather than a full libcubeb update: - wasapi-output-mix-channel-count.patch: upstream cubeb dc56ea41 and f0bd97db (mozilla/cubeb#856), bug 2061220. Creates the output mixer when the device mix channel count differs from the stream channel count, and rejects stream params whose layout and channel count disagree. - winmm-destroy-work-item-uaf.patch: upstream cubeb f6b59a3b (mozilla/cubeb#854), bug 2058051. Counts pending buffer thread work items per stream and in-flight driver callbacks per context so stream and context destruction wait for them to drain. Differential Revision: https://phabricator.services.mozilla.com/D319946
lando-worker Bot
pushed a commit
to mozilla-firefox/firefox
that referenced
this pull request
Aug 20, 2026
… and WinMM stream destroy fixes. a=RyanVM DONTBUILD This branch pins an older libcubeb revision, so the two fixes are carried as local vendoring patches rather than a full libcubeb update: - wasapi-output-mix-channel-count.patch: upstream cubeb dc56ea41 and f0bd97db (mozilla/cubeb#856), bug 2061220. Creates the output mixer when the device mix channel count differs from the stream channel count, and rejects stream params whose layout and channel count disagree. - winmm-destroy-work-item-uaf.patch: upstream cubeb f6b59a3b (mozilla/cubeb#854), bug 2058051. Counts pending buffer thread work items per stream and in-flight driver callbacks per context so stream and context destruction wait for them to drain. Differential Revision: https://phabricator.services.mozilla.com/D319947
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Destroy could free a stream while buffer thread work items referencing it were still queued or in flight, particularly after a data callback error. Count pending work items per stream (and in-flight driver callbacks per context) and make destroy wait for them to drain. Also fix free_buffers accounting on refill's error paths so the wait terminates.