Vulnerability · Published Sep 11, 2025 · Assigned by Linux
CVE-2025-39745rcutorture: Fix rcutorture_one_extend_check() splat in RT kernels
Medium 5.5
In plain English
A medium-severity security flaw in Linux from Linux. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 5% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
In the Linux kernel, the following vulnerability has been resolved: rcutorture: Fix rcutorture_one_extend_check() splat in RT kernels For built with CONFIG_PREEMPT_RT=y kernels, running rcutorture tests resulted in the following splat: [ 68.797425] rcutorture_one_extend_check during change: Current 0x1 To add 0x1 To remove 0x0 preempt_count() 0x0 [ 68.797533] WARNING: CPU: 2 PID: 512 at kernel/rcu/rcutorture.c:1993 rcutorture_one_extend_check+0x419/0x560 [rcutorture] [ 68.797601] Call Trace: [ 68.797602] <TASK> [ 68.797619] ? lockdep_softirqs_off+0xa5/0x160 [ 68.797631] rcutorture_one_extend+0x18e/0xcc0 [rcutorture 2466dbd2ff34dbaa36049cb323a80c3306ac997c] [ 68.797646] ? local_clock+0x19/0x40 [ 68.797659] rcu_torture_one_read+0xf0/0x280 [rcutorture 2466dbd2ff34dbaa36049cb323a80c3306ac997c] [ 68.797678] ? __pfx_rcu_torture_one_read+0x10/0x10 [rcutorture 2466dbd2ff34dbaa36049cb323a80c3306ac997c] [ 68.797804] ? __pfx_rcu_torture_timer+0x10/0x10 [rcutorture 2466dbd2ff34dbaa36049cb323a80c3306ac997c] [ 68.797815] rcu-torture: rcu_torture_reader task started [ 68.797824] rcu-torture: Creating rcu_torture_reader task [ 68.797824] rcu_torture_reader+0x238/0x580 [rcutorture 2466dbd2ff34dbaa36049cb323a80c3306ac997c] [ 68.797836] ? kvm_sched_clock_read+0x15/0x30 Disable BH does not change the SOFTIRQ corresponding bits in preempt_count() for RT kernels, this commit therefore use softirq_count() to check the if BH is disabled.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | linux | no fix listed | DEBIAN-CVE-2025-39745 |
| Debian:13 | linux | no fix listed | DEBIAN-CVE-2025-39745 |
| Debian:14 | linux | 6.16.3-1 | DEBIAN-CVE-2025-39745 |
| Ubuntu:22.04:LTS | linux-allwinner-5.19 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:22.04:LTS | linux-aws-5.19 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:24.04:LTS | linux-aws-6.14 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:22.04:LTS | linux-aws-6.2 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:22.04:LTS | linux-aws-6.5 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:22.04:LTS | linux-azure-5.19 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:24.04:LTS | linux-azure-6.11 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:24.04:LTS | linux-azure-6.14 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:22.04:LTS | linux-azure-6.2 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:22.04:LTS | linux-azure-6.5 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:25.10 | linux-azure-fde | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:22.04:LTS | linux-azure-fde-5.19 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:24.04:LTS | linux-azure-fde-6.14 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:24.04:LTS | linux-azure-fde-6.17 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:22.04:LTS | linux-azure-fde-6.2 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:24.04:LTS | linux-azure-nvidia-6.14 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:22.04:LTS | linux-gcp-5.19 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:24.04:LTS | linux-gcp-6.11 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:24.04:LTS | linux-gcp-6.14 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:22.04:LTS | linux-gcp-6.2 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:22.04:LTS | linux-gcp-6.5 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:22.04:LTS | linux-hwe-5.19 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:24.04:LTS | linux-hwe-6.11 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:24.04:LTS | linux-hwe-6.14 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:22.04:LTS | linux-hwe-6.2 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:22.04:LTS | linux-hwe-6.5 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:24.04:LTS | linux-intel | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:22.04:LTS | linux-intel-iot-realtime | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:22.04:LTS | linux-lowlatency-hwe-5.19 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:24.04:LTS | linux-lowlatency-hwe-6.11 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:22.04:LTS | linux-lowlatency-hwe-6.2 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:22.04:LTS | linux-lowlatency-hwe-6.5 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:24.04:LTS | linux-nvidia-6.11 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:22.04:LTS | linux-nvidia-6.2 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:22.04:LTS | linux-nvidia-6.5 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:22.04:LTS | linux-oem-5.17 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:22.04:LTS | linux-oem-6.0 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:22.04:LTS | linux-oem-6.1 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:24.04:LTS | linux-oem-6.11 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:24.04:LTS | linux-oem-6.14 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:22.04:LTS | linux-oem-6.5 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:24.04:LTS | linux-oem-6.8 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:24.04:LTS | linux-oracle-6.14 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:22.04:LTS | linux-oracle-6.5 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:24.04:LTS | linux-raspi-realtime | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:22.04:LTS | linux-realtime | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:24.04:LTS | linux-realtime | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:22.04:LTS | linux-riscv | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:24.04:LTS | linux-riscv | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:22.04:LTS | linux-riscv-5.19 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:24.04:LTS | linux-riscv-6.14 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:22.04:LTS | linux-riscv-6.5 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:22.04:LTS | linux-starfive-5.19 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:22.04:LTS | linux-starfive-6.2 | no fix listed | UBUNTU-CVE-2025-39745 |
| Ubuntu:22.04:LTS | linux-starfive-6.5 | no fix listed | UBUNTU-CVE-2025-39745 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Linux | Linux | ec9d6356bfda69abe5f4767dd56c964127913233 – before a85550267247cdf5e7499be00ea8e388ab014e50ec9d6356bfda69abe5f4767dd56c964127913233 – before 69c5ae0f441c2d72e8f48dc1e08464c172360c4cec9d6356bfda69abe5f4767dd56c964127913233 – before 8d71351d88e478d3c4e945e3218e97ec677fd807 |
| Linux | Linux | 6.14 |