scs: fix a wrong parameter in __scs_magic (Linux Linux)

CVE-2025-71102
MEDIUM 5.5

At a glance

Source
NVD
EPSS
EPSS 0.15 % · percentile 4 ()
State
PUBLISHED
Published
Updated
Assigner
Linux
NVD status
Analyzed

Description

In the Linux kernel, the following vulnerability has been resolved: scs: fix a wrong parameter in __scs_magic __scs_magic() needs a 'void *' variable, but a 'struct task_struct *' is given. 'task_scs(tsk)' is the starting address of the task's shadow call stack, and '__scs_magic(task_scs(tsk))' is the end address of the task's shadow call stack. Here should be '__scs_magic(task_scs(tsk))'. The user-visible effect of this bug is that when CONFIG_DEBUG_STACK_USAGE is enabled, the shadow call stack usage checking function (scs_check_usage) would scan an incorrect memory range. This could lead 1. **Inaccurate stack usage reporting**: The function would calculate wrong usage statistics for the shadow call stack, potentially showing incorrect value in kmsg. 2. **Potential kernel crash**: If the value of __scs_magic(tsk)is greater than that of __scs_magic(task_scs(tsk)), the for loop may access unmapped memory, potentially causing a kernel panic. However, this scenario is unlikely because task_struct is allocated via the slab allocator (which typically returns lower addresses), while the shadow call stack returned by task_scs(tsk) is allocated via vmalloc(which typically returns higher addresses). However, since this is purely a debugging feature (CONFIG_DEBUG_STACK_USAGE), normal production systems should be not unaffected. The bug only impacts developers and testers who are actively debugging stack usage with this configuration enabled.

References

Scores

VersionScoreVectorScored by
CVSS 3.1MEDIUM 5.5CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:HNVD · nvd@nist.gov (Primary)

European references

CERT-FR advisories

Affected configurations (NVD CPE)

Affected products

ProductVersions
Linux · Linuxaffected 5bbaf9d1fcb9be696ee9a61636ab6803556c70f2 < 1727e8bd69103a68963a5613a0ddb6d8d37df5d3 ; affected 5bbaf9d1fcb9be696ee9a61636ab6803556c70f2 < cfdf6250b63b953b1d8e60814c8ca96c6f9d1c8c ; affected 5bbaf9d1fcb9be696ee9a61636ab6803556c70f2 < 57ba40b001be27786d0570dd292289df748b306b ; affected 5bbaf9d1fcb9be696ee9a61636ab6803556c70f2 < 062774439d442882b44f5eab8c256ad3423ef284 ; affected 5bbaf9d1fcb9be696ee9a61636ab6803556c70f2 < 9ef28943471a16e4f9646bc3e8e2de148e7d8d7b ; affected 5bbaf9d1fcb9be696ee9a61636ab6803556c70f2 < a19fb3611e4c06624fc0f83ef19f4fb8d57d4751
Linux · Linuxaffected 5.8 ; unaffected 0 < 5.8 ; unaffected 5.10.248 ≤ 5.10.* ; unaffected 5.15.198 ≤ 5.15.* ; unaffected 6.1.160 ≤ 6.1.* ; unaffected 6.6.120 ≤ 6.6.*

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD