worker: fix race condition in node_messaging.cc #33429
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`AddToIncomingQueue()` relies on `owner_` only being modified with `mutex_` being locked, but in these two places, that didn’t happen. Modify them to use `Detach()` instead, which has the same effect as setting `owner_ = nullptr` here, but does it with proper locking. This race condition probably only shows up in practice when Node.js is compiled in debug mode, because the compiler eliminates the duplicate load in `AddToIncomingQueue()` when compiling with optimizations enabled.
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cjihrig
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`AddToIncomingQueue()` relies on `owner_` only being modified with `mutex_` being locked, but in these two places, that didn’t happen. Modify them to use `Detach()` instead, which has the same effect as setting `owner_ = nullptr` here, but does it with proper locking. This race condition probably only shows up in practice when Node.js is compiled in debug mode, because the compiler eliminates the duplicate load in `AddToIncomingQueue()` when compiling with optimizations enabled. PR-URL: #33429 Reviewed-By: Colin Ihrig <cjihrig@gmail.com> Reviewed-By: David Carlier <devnexen@gmail.com> Reviewed-By: James M Snell <jasnell@gmail.com>
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`AddToIncomingQueue()` relies on `owner_` only being modified with `mutex_` being locked, but in these two places, that didn’t happen. Modify them to use `Detach()` instead, which has the same effect as setting `owner_ = nullptr` here, but does it with proper locking. This race condition probably only shows up in practice when Node.js is compiled in debug mode, because the compiler eliminates the duplicate load in `AddToIncomingQueue()` when compiling with optimizations enabled. PR-URL: #33429 Reviewed-By: Colin Ihrig <cjihrig@gmail.com> Reviewed-By: David Carlier <devnexen@gmail.com> Reviewed-By: James M Snell <jasnell@gmail.com>
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`AddToIncomingQueue()` relies on `owner_` only being modified with `mutex_` being locked, but in these two places, that didn’t happen. Modify them to use `Detach()` instead, which has the same effect as setting `owner_ = nullptr` here, but does it with proper locking. This race condition probably only shows up in practice when Node.js is compiled in debug mode, because the compiler eliminates the duplicate load in `AddToIncomingQueue()` when compiling with optimizations enabled. PR-URL: #33429 Reviewed-By: Colin Ihrig <cjihrig@gmail.com> Reviewed-By: David Carlier <devnexen@gmail.com> Reviewed-By: James M Snell <jasnell@gmail.com>
codebytere
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`AddToIncomingQueue()` relies on `owner_` only being modified with `mutex_` being locked, but in these two places, that didn’t happen. Modify them to use `Detach()` instead, which has the same effect as setting `owner_ = nullptr` here, but does it with proper locking. This race condition probably only shows up in practice when Node.js is compiled in debug mode, because the compiler eliminates the duplicate load in `AddToIncomingQueue()` when compiling with optimizations enabled. PR-URL: #33429 Reviewed-By: Colin Ihrig <cjihrig@gmail.com> Reviewed-By: David Carlier <devnexen@gmail.com> Reviewed-By: James M Snell <jasnell@gmail.com>
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AddToIncomingQueue()relies onowner_only being modified withmutex_being locked, but in these two places, that didn’t happen.Modify them to use
Detach()instead, which has the same effectas setting
owner_ = nullptrhere, but does it with proper locking.This race condition probably only shows up in practice when Node.js
is compiled in debug mode, because the compiler eliminates the
duplicate load in
AddToIncomingQueue()when compiling withoptimizations enabled.
(The other side of the race condition happens here:
node/src/node_messaging.cc
Lines 430 to 433 in 48b1595
)
Checklist
make -j4 test(UNIX), orvcbuild test(Windows) passes