An issue was discovered in fs/io_uring.c in the Linux kernel through 5.11.8. It allows attackers to cause a denial of service (deadlock) because exit may be waiting to park a SQPOLL thread but concurrently that SQPOLL thread is waiting for a signal to start aka CID-3ebba796fa25.

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CVE-2021-28951

An issue was discovered in fs/iouring.c in the Linux kernel through 5.11.8. It allows attackers to cause a denial of service deadlock because exit may be waiting to park a SQPOLL thread, but concurrently that SQPOLL thread is waiting for a signal to start, aka CID-3ebba796fa25...