Vulnerability CVE-2023-52633

Vulnerability CVE-2023-52633

Published: 2024-04-02

Description:

In the Linux kernel, the following vulnerability has been resolved:

um: time-travel: fix time corruption

In 'basic' time-travel mode (without =inf-cpu or =ext), we
still get timer interrupts. These can happen at arbitrary
points in time, i.e. while in timer_read(), which pushes
time forward just a little bit. Then, if we happen to get
the interrupt after calculating the new time to push to,
but before actually finishing that, the interrupt will set
the time to a value that's incompatible with the forward,
and we'll crash because time goes backwards when we do the
forwarding.

Fix this by reading the time_travel_time, calculating the
adjustment, and doing the adjustment all with interrupts
disabled.

References:

https://git.kernel.org/stable/c/0c7478a2da3f5fe106b4658338873d50c86ac7ab

https://git.kernel.org/stable/c/4f7dad73df4cdb2b7042103d3922745d040ad025

https://git.kernel.org/stable/c/de3e9d8e8d1ae0a4d301109d1ec140796901306c

https://git.kernel.org/stable/c/b427f55e9d4185f6f17cc1e3296eb8d0c4425283

https://git.kernel.org/stable/c/abe4eaa8618bb36c2b33e9cdde0499296a23448c

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