Ubuntu Security Notice 4367-1 - It was discovered that the btrfs implementation in the Linux kernel did not properly detect that a block was marked dirty in some situations. An attacker could use this to specially craft a file system image that, when unmounted, could cause a denial of service. It was discovered that the linux kernel did not properly validate certain mount options to the tmpfs virtual memory file system. A local attacker with the ability to specify mount options could use this to cause a denial of service. Various other issues were also addressed.
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