Linux Kernel up to 6.6.20/6.7.8 perf ctr_get_width null pointer dereference

Summaryinfo

A vulnerability classified as critical has been found in Linux Kernel up to 6.6.20/6.7.8. Affected is the function ctr_get_width of the component perf. Performing a manipulation results in null pointer dereference. This vulnerability is known as CVE-2024-26796. No exploit is available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability classified as critical has been found in Linux Kernel up to 6.6.20/6.7.8. This affects the function ctr_get_width of the component perf. The manipulation with an unknown input leads to a null pointer dereference vulnerability. CWE is classifying the issue as CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. This is going to have an impact on availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: drivers: perf: ctr_get_width function for legacy is not defined With parameters CONFIG_RISCV_PMU_LEGACY=y and CONFIG_RISCV_PMU_SBI=n linux kernel crashes when you try perf record: $ perf record ls [ 46.749286] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000 [ 46.750199] Oops [#1] [ 46.750342] Modules linked in: [ 46.750608] CPU: 0 PID: 107 Comm: perf-exec Not tainted 6.6.0 #2 [ 46.750906] Hardware name: riscv-virtio,qemu (DT) [ 46.751184] epc : 0x0 [ 46.751430] ra : arch_perf_update_userpage+0x54/0x13e [ 46.751680] epc : 0000000000000000 ra : ffffffff8072ee52 sp : ff2000000022b8f0 [ 46.751958] gp : ffffffff81505988 tp : ff6000000290d400 t0 : ff2000000022b9c0 [ 46.752229] t1 : 0000000000000001 t2 : 0000000000000003 s0 : ff2000000022b930 [ 46.752451] s1 : ff600000028fb000 a0 : 0000000000000000 a1 : ff600000028fb000 [ 46.752673] a2 : 0000000ae2751268 a3 : 00000000004fb708 a4 : 0000000000000004 [ 46.752895] a5 : 0000000000000000 a6 : 000000000017ffe3 a7 : 00000000000000d2 [ 46.753117] s2 : ff600000028fb000 s3 : 0000000ae2751268 s4 : 0000000000000000 [ 46.753338] s5 : ffffffff8153e290 s6 : ff600000863b9000 s7 : ff60000002961078 [ 46.753562] s8 : ff60000002961048 s9 : ff60000002961058 s10: 0000000000000001 [ 46.753783] s11: 0000000000000018 t3 : ffffffffffffffff t4 : ffffffffffffffff [ 46.754005] t5 : ff6000000292270c t6 : ff2000000022bb30 [ 46.754179] status: 0000000200000100 badaddr: 0000000000000000 cause: 000000000000000c [ 46.754653] Code: Unable to access instruction at 0xffffffffffffffec. [ 46.754939] ---[ end trace 0000000000000000 ]--- [ 46.755131] note: perf-exec[107] exited with irqs disabled [ 46.755546] note: perf-exec[107] exited with preempt_count 4 This happens because in the legacy case the ctr_get_width function was not defined, but it is used in arch_perf_update_userpage. Also remove extra check in riscv_pmu_ctr_get_width_mask

It is possible to read the advisory at git.kernel.org. This vulnerability is uniquely identified as CVE-2024-26796 since 02/19/2024. The exploitability is told to be difficult. Technical details of the vulnerability are known, but there is no available exploit.

Upgrading to version 6.6.21, 6.7.9 or 6.8 eliminates this vulnerability. Applying the patch e0d17ee872cf/e4f50e85de5a/682dc133f83e is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the vulnerability database at CERT Bund (WID-SEC-2024-0773). Be aware that VulDB is the high quality source for vulnerability data.

Affected

• Debian Linux
• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• IBM InfoSphere Guardium
• Oracle Linux
• NetApp FAS
• EMC Avamar
• Oracle VM
• NetApp AFF
• Dell NetWorker
• IBM Security Guardium
• RESF Rocky Linux
• Open Source Linux Kernel
• SolarWinds Security Event Manager
• Broadcom Brocade SANnav
• IBM Business Automation Workflow
• IBM Spectrum Protect Plus
• IBM QRadar SIEM
• Juniper Junos Space
• IBM DB2
• IBM Storage Scale System

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.6.0
• 6.6.1
• 6.6.2
• 6.6.3
• 6.6.4
• 6.6.5
• 6.6.6
• 6.6.7
• 6.6.8
• 6.6.9
• 6.6.10
• 6.6.11
• 6.6.12
• 6.6.13
• 6.6.14
• 6.6.15
• 6.6.16
• 6.6.17
• 6.6.18
• 6.6.19
• 6.6.20
• 6.7.0
• 6.7.1
• 6.7.2
• 6.7.3
• 6.7.4
• 6.7.5
• 6.7.6
• 6.7.7
• 6.7.8

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

• 🔍
• 🔍
• 🔍

CPE 2.2info

• 🔍
• 🔍
• 🔍

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

Be aware that VulDB is the high quality source for vulnerability data.

Discussion