In the Linux kernel, the following vulnerability has been resolved:
riscv: VMAP_STACK overflow detection thread-safe
commit 31da94c25aea ("riscv: add VMAP_STACK overflow detection") added
support for CONFIG_VMAP_STACK. If overflow is detected, CPU switches to
`shadow_stack` temporarily before switching finally to per-cpu
`overflow_stack`.
If two CPUs/harts are racing and end up in over flowing kernel stack, one
or both will end up corrupting each other state because `shadow_stack` is
not per-cpu. This patch optimizes per-cpu overflow stack switch by
directly picking per-cpu `overflow_stack` and gets rid of `shadow_stack`.
Following are the changes in this patch
- Defines an asm macro to obtain per-cpu symbols in destination
register.
- In entry.S, when overflow is detected, per-cpu overflow stack is
located using per-cpu asm macro. Computing per-cpu symbol requires
a temporary register. x31 is saved away into CSR_SCRATCH
(CSR_SCRATCH is anyways zero since we're in kernel).
Please see Links for additional relevant disccussion and alternative
solution.
Tested by `echo EXHAUST_STACK > /sys/kernel/debug/provoke-crash/DIRECT`
Kernel crash log below
Insufficient stack space to handle exception!/debug/provoke-crash/DIRECT
Task stack: [0xff20000010a98000..0xff20000010a9c000]
Overflow stack: [0xff600001f7d98370..0xff600001f7d99370]
CPU: 1 PID: 205 Comm: bash Not tainted 6.1.0-rc2-00001-g328a1f96f7b9 #34
Hardware name: riscv-virtio,qemu (DT)
epc : __memset+0x60/0xfc
ra : recursive_loop+0x48/0xc6 [lkdtm]
epc : ffffffff808de0e4 ra : ffffffff0163a752 sp : ff20000010a97e80
gp : ffffffff815c0330 tp : ff600000820ea280 t0 : ff20000010a97e88
t1 : 000000000000002e t2 : 3233206874706564 s0 : ff20000010a982b0
s1 : 0000000000000012 a0 : ff20000010a97e88 a1 : 0000000000000000
a2 : 0000000000000400 a3 : ff20000010a98288 a4 : 0000000000000000
a5 : 0000000000000000 a6 : fffffffffffe43f0 a7 : 00007fffffffffff
s2 : ff20000010a97e88 s3 : ffffffff01644680 s4 : ff20000010a9be90
s5 : ff600000842ba6c0 s6 : 00aaaaaac29e42b0 s7 : 00fffffff0aa3684
s8 : 00aaaaaac2978040 s9 : 0000000000000065 s10: 00ffffff8a7cad10
s11: 00ffffff8a76a4e0 t3 : ffffffff815dbaf4 t4 : ffffffff815dbaf4
t5 : ffffffff815dbab8 t6 : ff20000010a9bb48
status: 0000000200000120 badaddr: ff20000010a97e88 cause: 000000000000000f
Kernel panic - not syncing: Kernel stack overflow
CPU: 1 PID: 205 Comm: bash Not tainted 6.1.0-rc2-00001-g328a1f96f7b9 #34
Hardware name: riscv-virtio,qemu (DT)
Call Trace:
[<ffffffff80006754>] dump_backtrace+0x30/0x38
[<ffffffff808de798>] show_stack+0x40/0x4c
[<ffffffff808ea2a8>] dump_stack_lvl+0x44/0x5c
[<ffffffff808ea2d8>] dump_stack+0x18/0x20
[<ffffffff808dec06>] panic+0x126/0x2fe
[<ffffffff800065ea>] walk_stackframe+0x0/0xf0
[<ffffffff0163a752>] recursive_loop+0x48/0xc6 [lkdtm]
SMP: stopping secondary CPUs
---[ end Kernel panic - not syncing: Kernel stack overflow ]---
References
Configurations
Configuration 1 (hide)
|
History
23 Sep 2025, 19:28
Type | Values Removed | Values Added |
---|---|---|
References | () https://git.kernel.org/stable/c/1493baaf09e3c1899959c8a107cd1207e16d1788 - Patch | |
References | () https://git.kernel.org/stable/c/be97d0db5f44c0674480cb79ac6f5b0529b84c76 - Patch | |
References | () https://git.kernel.org/stable/c/eff53aea3855f71992c043cebb1c00988c17ee20 - Patch | |
First Time |
Linux linux Kernel
Linux |
|
CPE | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
CVSS |
v2 : v3 : |
v2 : unknown
v3 : 5.5 |
CWE | CWE-674 |
21 Nov 2024, 08:40
Type | Values Removed | Values Added |
---|---|---|
References | () https://git.kernel.org/stable/c/1493baaf09e3c1899959c8a107cd1207e16d1788 - | |
References | () https://git.kernel.org/stable/c/be97d0db5f44c0674480cb79ac6f5b0529b84c76 - | |
References | () https://git.kernel.org/stable/c/eff53aea3855f71992c043cebb1c00988c17ee20 - | |
Summary |
|
21 May 2024, 16:15
Type | Values Removed | Values Added |
---|---|---|
New CVE |
Information
Published : 2024-05-21 16:15
Updated : 2025-09-23 19:28
NVD link : CVE-2023-52761
Mitre link : CVE-2023-52761
CVE.ORG link : CVE-2023-52761
JSON object : View
Products Affected
linux
- linux_kernel
CWE
CWE-674
Uncontrolled Recursion