Ubuntu: (Multiple Advisories) (CVE-2025-21767): Linux kernel vulnerabilities
Description
In the Linux kernel, the following vulnerability has been resolved: clocksource: Use migrate_disable() to avoid calling get_random_u32() in atomic context The following bug report happened with a PREEMPT_RT kernel: BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:48 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 2012, name: kwatchdog preempt_count: 1, expected: 0 RCU nest depth: 0, expected: 0 get_random_u32+0x4f/0x110 clocksource_verify_choose_cpus+0xab/0x1a0 clocksource_verify_percpu.part.0+0x6b/0x330 clocksource_watchdog_kthread+0x193/0x1a0 It is due to the fact that clocksource_verify_choose_cpus() is invoked with preemption disabled. This function invokes get_random_u32() to obtain random numbers for choosing CPUs. The batched_entropy_32 local lock and/or the base_crng.lock spinlock in driver/char/random.c will be acquired during the call. In PREEMPT_RT kernel, they are both sleeping locks and so cannot be acquired in atomic context. Fix this problem by using migrate_disable() to allow smp_processor_id() to be reliably used without introducing atomic context. preempt_disable() is then called after clocksource_verify_choose_cpus() but before the clocksource measurement is being run to avoid introducing unexpected latency.
Solution(s)
- ubuntu-upgrade-linux-image-5-15-0-1026-nvidia-tegra-igx
- ubuntu-upgrade-linux-image-5-15-0-1026-nvidia-tegra-igx-rt
- ubuntu-upgrade-linux-image-5-15-0-1037-nvidia-tegra
- ubuntu-upgrade-linux-image-5-15-0-1037-nvidia-tegra-rt
- ubuntu-upgrade-linux-image-5-15-0-1066-gkeop
- ubuntu-upgrade-linux-image-5-15-0-1076-ibm
- ubuntu-upgrade-linux-image-5-15-0-1077-intel-iot-realtime
- ubuntu-upgrade-linux-image-5-15-0-1078-nvidia
- ubuntu-upgrade-linux-image-5-15-0-1078-nvidia-lowlatency
- ubuntu-upgrade-linux-image-5-15-0-1078-raspi
- ubuntu-upgrade-linux-image-5-15-0-1079-intel-iotg
- ubuntu-upgrade-linux-image-5-15-0-1080-kvm
- ubuntu-upgrade-linux-image-5-15-0-1081-gke
- ubuntu-upgrade-linux-image-5-15-0-1081-oracle
- ubuntu-upgrade-linux-image-5-15-0-1083-gcp
- ubuntu-upgrade-linux-image-5-15-0-1083-gcp-fips
- ubuntu-upgrade-linux-image-5-15-0-1084-aws
- ubuntu-upgrade-linux-image-5-15-0-1084-aws-fips
- ubuntu-upgrade-linux-image-5-15-0-1084-realtime
- ubuntu-upgrade-linux-image-5-15-0-1089-azure
- ubuntu-upgrade-linux-image-5-15-0-1089-azure-fips
- ubuntu-upgrade-linux-image-5-15-0-140-fips
- ubuntu-upgrade-linux-image-5-15-0-140-generic
- ubuntu-upgrade-linux-image-5-15-0-140-generic-64k
- ubuntu-upgrade-linux-image-5-15-0-140-generic-lpae
- ubuntu-upgrade-linux-image-5-15-0-140-lowlatency
- ubuntu-upgrade-linux-image-5-15-0-140-lowlatency-64k
- ubuntu-upgrade-linux-image-6-11-0-1010-realtime
- ubuntu-upgrade-linux-image-6-11-0-1013-raspi
- ubuntu-upgrade-linux-image-6-11-0-1014-aws
- ubuntu-upgrade-linux-image-6-11-0-1014-lowlatency
- ubuntu-upgrade-linux-image-6-11-0-1014-lowlatency-64k
- ubuntu-upgrade-linux-image-6-11-0-1015-azure
- ubuntu-upgrade-linux-image-6-11-0-1015-azure-fde
- ubuntu-upgrade-linux-image-6-11-0-1015-gcp
- ubuntu-upgrade-linux-image-6-11-0-1015-gcp-64k
- ubuntu-upgrade-linux-image-6-11-0-1016-oracle
- ubuntu-upgrade-linux-image-6-11-0-1016-oracle-64k
- ubuntu-upgrade-linux-image-6-11-0-1022-oem
- ubuntu-upgrade-linux-image-6-11-0-26-generic
- ubuntu-upgrade-linux-image-6-11-0-26-generic-64k
- ubuntu-upgrade-linux-image-aws
- ubuntu-upgrade-linux-image-aws-fips
- ubuntu-upgrade-linux-image-aws-lts-22-04
- ubuntu-upgrade-linux-image-azure
- ubuntu-upgrade-linux-image-azure-cvm
- ubuntu-upgrade-linux-image-azure-fde
- ubuntu-upgrade-linux-image-azure-fips
- ubuntu-upgrade-linux-image-azure-lts-22-04
- ubuntu-upgrade-linux-image-fips
- ubuntu-upgrade-linux-image-gcp
- ubuntu-upgrade-linux-image-gcp-64k
- ubuntu-upgrade-linux-image-gcp-fips
- ubuntu-upgrade-linux-image-gcp-lts-22-04
- ubuntu-upgrade-linux-image-generic
- ubuntu-upgrade-linux-image-generic-64k
- ubuntu-upgrade-linux-image-generic-64k-hwe-24-04
- ubuntu-upgrade-linux-image-generic-hwe-24-04
- ubuntu-upgrade-linux-image-generic-lpae
- ubuntu-upgrade-linux-image-gke
- ubuntu-upgrade-linux-image-gke-5-15
- ubuntu-upgrade-linux-image-gkeop
- ubuntu-upgrade-linux-image-gkeop-5-15
- ubuntu-upgrade-linux-image-ibm
- ubuntu-upgrade-linux-image-intel
- ubuntu-upgrade-linux-image-intel-iot-realtime
- ubuntu-upgrade-linux-image-intel-iotg
- ubuntu-upgrade-linux-image-kvm
- ubuntu-upgrade-linux-image-lowlatency
- ubuntu-upgrade-linux-image-lowlatency-64k
- ubuntu-upgrade-linux-image-lowlatency-64k-hwe-20-04
- ubuntu-upgrade-linux-image-lowlatency-64k-hwe-24-04
- ubuntu-upgrade-linux-image-lowlatency-hwe-20-04
- ubuntu-upgrade-linux-image-lowlatency-hwe-24-04
- ubuntu-upgrade-linux-image-nvidia
- ubuntu-upgrade-linux-image-nvidia-lowlatency
- ubuntu-upgrade-linux-image-nvidia-tegra
- ubuntu-upgrade-linux-image-nvidia-tegra-igx
- ubuntu-upgrade-linux-image-nvidia-tegra-igx-rt
- ubuntu-upgrade-linux-image-nvidia-tegra-rt
- ubuntu-upgrade-linux-image-oem-24-04b
- ubuntu-upgrade-linux-image-oracle
- ubuntu-upgrade-linux-image-oracle-64k
- ubuntu-upgrade-linux-image-oracle-lts-22-04
- ubuntu-upgrade-linux-image-raspi
- ubuntu-upgrade-linux-image-raspi-nolpae
- ubuntu-upgrade-linux-image-realtime
- ubuntu-upgrade-linux-image-virtual
- ubuntu-upgrade-linux-image-virtual-hwe-24-04
- Lightweight Endpoint Agent
- Live Dashboards
- Real Risk Prioritization
- IT-Integrated Remediation Projects
- Cloud, Virtual, and Container Assessment
- Integrated Threat Feeds
- Easy-to-Use RESTful API
- Automation-Assisted Patching
- Automated Containment
With Rapid7 live dashboards, I have a clear view of all the assets on my network, which ones can be exploited, and what I need to do in order to reduce the risk in my environment in real-time. No other tool gives us that kind of value and insight.
– Scott Cheney, Manager of Information Security, Sierra View Medical Center