unlocking the rtld bind lock results in the processing of ast and recursing into the check_deferred_signal(). Nested execution of check_deferred_signal() delivers the signal to user code and clears si_signo. On return, top-level check_deferred_signal() frame continues delivering the same signal one more time, but now with zero si_signo. Fix this by adding a flag to indicate that deferred delivery is running, so check_deferred_signal() should avoid doing anything. Since user signal handler is allowed to modify the passed machine context to make return from the signal handler to cause arbitrary jump, or do longjmp(). For this case, also clear the flag in thr_sighandler(), since kernel signal delivery means that nested delivery code should not run right now. Reported by: Vitaly Magerya <vmagerya@gmail.com> Reviewed by: davidxu, jilles Tested by: pho Sponsored by: The FreeBSD Foundation MFC after: 1 week |
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arch | ||
support | ||
sys | ||
thread | ||
libthr.3 | ||
Makefile | ||
pthread.map |