In the Linux kernel, the following vulnerability has been resolved:
rcu: Avoid stack overflow due to __rcu_irq_enter_check_tick() being kprobe-ed
Registering a kprobe on __rcu_irq_enter_check_tick() can cause kernel stack overflow as shown below. This issue can be reproduced by enabling CONFIG_NO_HZ_FULL and booting the kernel with argument "nohz_full=", and then giving the following commands at the shell prompt:
# cd /sys/kernel/tracing/ # echo 'p:mp1 __rcu_irq_enter_check_tick' >> kprobe_events # echo 1 > events/kprobes/enable
This commit therefore adds __rcu_irq_enter_check_tick() to the kprobes blacklist using NOKPROBE_SYMBOL().
Insufficient stack space to handle exception! ESR: 0x00000000f2000004 -- BRK (AArch64) FAR: 0x0000ffffccf3e510 Task stack: [0xffff80000ad30000..0xffff80000ad38000] IRQ stack: [0xffff800008050000..0xffff800008058000] Overflow stack: [0xffff089c36f9f310..0xffff089c36fa0310] CPU: 5 PID: 190 Comm: bash Not tainted 6.2.0-rc2-00320-g1f5abbd77e2c #19 Hardware name: linux,dummy-virt (DT) pstate: 400003c5 (nZcv DAIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : __rcu_irq_enter_check_tick+0x0/0x1b8 lr : ct_nmi_enter+0x11c/0x138 sp : ffff80000ad30080 x29: ffff80000ad30080 x28: ffff089c82e20000 x27: 0000000000000000 x26: 0000000000000000 x25: ffff089c02a8d100 x24: 0000000000000000 x23: 00000000400003c5 x22: 0000ffffccf3e510 x21: ffff089c36fae148 x20: ffff80000ad30120 x19: ffffa8da8fcce148 x18: 0000000000000000 x17: 0000000000000000 x16: 0000000000000000 x15: ffffa8da8e44ea6c x14: ffffa8da8e44e968 x13: ffffa8da8e03136c x12: 1fffe113804d6809 x11: ffff6113804d6809 x10: 0000000000000a60 x9 : dfff800000000000 x8 : ffff089c026b404f x7 : 00009eec7fb297f7 x6 : 0000000000000001 x5 : ffff80000ad30120 x4 : dfff800000000000 x3 : ffffa8da8e3016f4 x2 : 0000000000000003 x1 : 0000000000000000 x0 : 0000000000000000 Kernel panic - not syncing: kernel stack overflow CPU: 5 PID: 190 Comm: bash Not tainted 6.2.0-rc2-00320-g1f5abbd77e2c #19 Hardware name: linux,dummy-virt (DT) Call trace: dump_backtrace+0xf8/0x108 show_stack+0x20/0x30 dump_stack_lvl+0x68/0x84 dump_stack+0x1c/0x38 panic+0x214/0x404 add_taint+0x0/0xf8 panic_bad_stack+0x144/0x160 handle_bad_stack+0x38/0x58 __bad_stack+0x78/0x7c __rcu_irq_enter_check_tick+0x0/0x1b8 arm64_enter_el1_dbg.isra.0+0x14/0x20 el1_dbg+0x2c/0x90 el1h_64_sync_handler+0xcc/0xe8 el1h_64_sync+0x64/0x68 __rcu_irq_enter_check_tick+0x0/0x1b8 arm64_enter_el1_dbg.isra.0+0x14/0x20 el1_dbg+0x2c/0x90 el1h_64_sync_handler+0xcc/0xe8 el1h_64_sync+0x64/0x68 __rcu_irq_enter_check_tick+0x0/0x1b8 arm64_enter_el1_dbg.isra.0+0x14/0x20 el1_dbg+0x2c/0x90 el1h_64_sync_handler+0xcc/0xe8 el1h_64_sync+0x64/0x68 __rcu_irq_enter_check_tick+0x0/0x1b8 [...] el1_dbg+0x2c/0x90 el1h_64_sync_handler+0xcc/0xe8 el1h_64_sync+0x64/0x68 __rcu_irq_enter_check_tick+0x0/0x1b8 arm64_enter_el1_dbg.isra.0+0x14/0x20 el1_dbg+0x2c/0x90 el1h_64_sync_handler+0xcc/0xe8 el1h_64_sync+0x64/0x68 __rcu_irq_enter_check_tick+0x0/0x1b8 arm64_enter_el1_dbg.isra.0+0x14/0x20 el1_dbg+0x2c/0x90 el1h_64_sync_handler+0xcc/0xe8 el1h_64_sync+0x64/0x68 __rcu_irq_enter_check_tick+0x0/0x1b8 el1_interrupt+0x28/0x60 el1h_64_irq_handler+0x18/0x28 el1h_64_irq+0x64/0x68 __ftrace_set_clr_event_nolock+0x98/0x198 __ftrace_set_clr_event+0x58/0x80 system_enable_write+0x144/0x178 vfs_write+0x174/0x738 ksys_write+0xd0/0x188 __arm64_sys_write+0x4c/0x60 invoke_syscall+0x64/0x180 el0_svc_common.constprop.0+0x84/0x160 do_el0_svc+0x48/0xe8 el0_svc+0x34/0xd0 el0t_64_sync_handler+0xb8/0xc0 el0t_64_sync+0x190/0x194 SMP: stopping secondary CPUs Kernel Offset: 0x28da86000000 from 0xffff800008000000 PHYS_OFFSET: 0xfffff76600000000 CPU features: 0x00000,01a00100,0000421b Memory Limit: none
CVSS Details
- CVSS 3.1 Base Score: 5.5
- CVSS 3.1 Vector: (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H)
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Amazon Linux Ami 2 | — | Upgrade kernel-debuginfoUpgrade kernelUpgrade bpftool-debuginfoUpgrade kernel-headersUpgrade kernel-debuginfo-common-x86_64Upgrade python-perfUpgrade bpftoolUpgrade python-perf-debuginfoUpgrade kernel-debuginfo-common-aarch64Upgrade kernel-tools-develUpgrade perfUpgrade kernel-livepatch-5.15.117-72.142Upgrade kernel-develUpgrade kernel-toolsUpgrade kernel-tools-debuginfoUpgrade perf-debuginfoUpgrade kernel-livepatch-5.10.184-174.730 | May 20, 2026 | May 20, 2026 |
| Amazon_linux_2023 | — | Upgrade kernel-libbpfUpgrade kernel-libbpf-develUpgrade kernel-headersUpgrade kernelUpgrade kernel-debuginfo-common-x86_64Upgrade kernel-libbpf-staticUpgrade kernel-debuginfoUpgrade bpftool-debuginfoUpgrade kernel-tools-debuginfoUpgrade kernel-livepatch-6.1.29-47.49Upgrade bpftoolUpgrade perf-debuginfoUpgrade kernel-debuginfo-common-aarch64Upgrade kernel-toolsUpgrade perfUpgrade python3-perfUpgrade kernel-develUpgrade python3-perf-debuginfoUpgrade kernel-tools-devel | Oct 24, 2025 | Oct 7, 2025 |
| Debian | — | Upgrade linux | Oct 9, 2025 | Oct 9, 2025 |
| Huawei Euleros 2_0_sp13 | — | Upgrade kernel-toolsUpgrade kernel-tools-libsUpgrade bpftoolUpgrade kernel-abi-stablelistsUpgrade python3-perfUpgrade kernel | Feb 3, 2026 | Feb 2, 2026 |
| Redhat_linux | — | No solution existsUpgrade kernelUpgrade kernel-rt | Nov 14, 2025 | Oct 7, 2025 |
| Ubuntu | — | Upgrade linux-azure-5.15Upgrade linux-oracleUpgrade linux-gcpUpgrade linux-riscv-5.15Upgrade linux-intel-iotgUpgrade linux-oracle-5.15Upgrade linux-xilinx-zynqmpUpgrade linux-nvidia-tegra-5.15Upgrade linux-raspiUpgrade linux-ibmUpgrade linux-realtimeUpgrade linux-gkeUpgrade linux-ibm-5.15Upgrade linux-awsUpgrade linux-hwe-5.15Upgrade linux-intel-iotg-5.15Upgrade linux-bluefieldUpgrade linux-nvidia-tegra-igxUpgrade linux-intel-iot-realtimeUpgrade linuxUpgrade linux-azureUpgrade linux-lowlatency-hwe-5.15 | Oct 10, 2025 | Oct 7, 2025 |
| Vmware Photon_os | — | Use 'tdnf update' to upgrade all packages to the latest version. | Oct 15, 2025 | Oct 7, 2025 |
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