Fix stack overflow handling with SuperPMI #106495
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When SuperPMI shared library is loaded last, its SIGSEGV handler is the first one that's executed. But since there is no coreclr runtime handler installed for it, it returns from the SwitchStackAndExecuteHandler in case of SIGSEGV. The remaining code in the SIGSEGV handler was not expecting that and thought that there was no stack overflow and attempted to run the hardware exception handler on the original stack of the thread, which obviously crashed since the original stack overflowed. The fix is to make sure that we only call the previously registered signal handler in this case. Close dotnet#84911
jkotas
reviewed
Aug 15, 2024
| // hardware signal handler on the original stack. | ||
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| if (GetCurrentPalThread() && IsRunningOnAlternateStack(context)) | ||
| if (!isStackOverflow) |
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| if (!isStackOverflow) | |
| else |
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jkotas
approved these changes
Aug 15, 2024
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/azp run runtime-coreclr superpmi-collect |
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When SuperPMI shared library is loaded last, its SIGSEGV handler is the first one that's executed. But since there is no coreclr runtime handler installed for it, it returns from the SwitchStackAndExecuteHandler in case of SIGSEGV. The remaining code in the SIGSEGV handler was not expecting that and thought that there was no stack overflow and attempted to run the hardware exception handler on the original stack of the thread, which obviously crashed since the original stack overflowed.
The fix is to make sure that we only call the previously registered signal handler in this case.
Close #84911