CVE-2023-53998

Description

In the Linux kernel, the following vulnerability has been resolved:hwrng: virtio - Fix race on data_avail and actual dataThe virtio rng device kicks off a new entropy request whenever thedata available reaches zero. When a new request occurs at the endof a read operation, that is, when the result of that request isonly needed by the next reader, then there is a race between thewriting of the new data and the next reader.This is because there is no synchronisation whatsoever between thewriter and the reader.Fix this by writing data_avail with smp_store_release and readingit with smp_load_acquire when we first enter read. The subsequentreads are safe because theyre either protected by the first loadacquire, or by the completion mechanism.Also remove the redundant zeroing of data_idx in random_recv_done(data_idx must already be zero at this point) and data_avail inrequest_entropy (ditto).

Risk Information

Associated Vulnerability

Patch Details

References

https://nvd.nist.gov/vuln/detail/CVE-2023-1234
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-1234