| Name | CVE-2024-26796 |
| Description | 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 |
| Source | CVE (at NVD; CERT, LWN, oss-sec, fulldisc, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
Vulnerable and fixed packages
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|
| linux (PTS) | jessie, jessie (lts) | 3.16.84-1 | vulnerable |
| stretch (security) | 4.9.320-2 | vulnerable |
| stretch (lts), stretch | 4.9.320-3 | vulnerable |
| buster (security), buster, buster (lts) | 4.19.316-1 | fixed |
| bullseye | 5.10.223-1 | fixed |
| bullseye (security) | 5.10.226-1 | fixed |
| bookworm | 6.1.115-1 | fixed |
| bookworm (security) | 6.1.119-1 | fixed |
| trixie | 6.12.5-1 | fixed |
| sid | 6.12.6-1 | fixed |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|
| linux | source | jessie | (unfixed) | end-of-life | | |
| linux | source | stretch | (unfixed) | end-of-life | | |
| linux | source | buster | (not affected) | | | |
| linux | source | bullseye | (not affected) | | | |
| linux | source | bookworm | (not affected) | | | |
| linux | source | (unstable) | 6.7.9-1 | | | |
Notes
[bookworm] - linux <not-affected> (Vulnerable code not present)
[bullseye] - linux <not-affected> (Vulnerable code not present)
[buster] - linux <not-affected> (Vulnerable code not present)
https://git.kernel.org/linus/682dc133f83e0194796e6ea72eb642df1c03dfbe (6.8-rc7)