Ubuntu Security Notice 4660-2 - USN-4660-1 fixed vulnerabilities in the Linux kernel. Unfortunately, that update introduced a regression in the software raid10 driver when used with fstrim that could lead to data corruption. This update fixes the problem. It was discovered that a race condition existed in the perf subsystem of the Linux kernel, leading to a use-after-free vulnerability. An attacker with access to the perf subsystem could use this to cause a denial of service or possibly execute arbitrary code. Various other issues were also addressed.
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