USN-5091-3: Linux kernel (Azure) regression
USN-5091-3: Linux kernel (Azure) regression USN-5091-1 fixed vulnerabilities in Linux 5.4-based kernels. Unfortunately, for Linux kernels intended for use within Microsoft Azure environments, that update introduced a regression that could cause the kernel to fail to boot in large Azure instance types. This update fixes the problem. We apologize for the inconvenience. Original advisory details: Ofek Kirzner, Adam Morrison, Benedict Schlueter, and Piotr Krysiuk discovered that the BPF verifier in the Linux kernel missed possible mispredicted branches due to type confusion, allowing a side-channel attack. An attacker could use this to expose sensitive information. (CVE-2021-33624) It was discovered that the tracing subsystem in the Linux kernel did not properly keep track of per-cpu ring buffer state. A privileged attacker could use this to cause a denial of service. (CVE-2021-3679) Alexey Kardashevskiy discovered that the KVM implementation for PowerPC systems in [ more… ]
