kernel: be more careful about dup_mmap() failures and uprobe registering
Summary
| CVE | CVE-2025-21709 |
|---|---|
| State | PUBLISHED |
| Assigner | Linux |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2025-02-27 02:15:14 UTC |
| Updated | 2026-04-22 13:16:18 UTC |
| Description | In the Linux kernel, the following vulnerability has been resolved: kernel: be more careful about dup_mmap() failures and uprobe registering If a memory allocation fails during dup_mmap(), the maple tree can be left in an unsafe state for other iterators besides the exit path. All the locks are dropped before the exit_mmap() call (in mm/mmap.c), but the incomplete mm_struct can be reached through (at least) the rmap finding the vmas which have a pointer back to the mm_struct. Up to this point, there have been no issues with being able to find an mm_struct that was only partially initialised. Syzbot was able to make the incomplete mm_struct fail with recent forking changes, so it has been proven unsafe to use the mm_struct that hasn't been initialised, as referenced in the link below. Although 8ac662f5da19f ("fork: avoid inappropriate uprobe access to invalid mm") fixed the uprobe access, it does not completely remove the race. This patch sets the MMF_OOM_SKIP to avoid the iteration of the vmas on the oom side (even though this is extremely unlikely to be selected as an oom victim in the race window), and sets MMF_UNSTABLE to avoid other potential users from using a partially initialised mm_struct. When registering vmas for uprobe, skip the vmas in an mm that is marked unstable. Modifying a vma in an unstable mm may cause issues if the mm isn't fully initialised. |
Risk And Classification
Primary CVSS: v3.1 5.5 MEDIUM from [email protected]
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Problem Types: NVD-CWE-noinfo
CVSS v3.1 Breakdown
Attack Vector
LocalAttack Complexity
LowPrivileges Required
LowUser Interaction
NoneScope
UnchangedConfidentiality
NoneIntegrity
NoneAvailability
HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
NVD Known Affected Configurations (CPE 2.3)
| Type | Vendor | Product | Version | Update | Edition | Language |
|---|---|---|---|---|---|---|
| Operating System | Linux | Linux Kernel | All | All | All | All |
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Linux | Linux | affected d2406291483775ecddaee929231a39c70c08fda2 74c2471eb891a7dcb3874b21c106cda75f52be30 git | Not specified |
| CNA | Linux | Linux | affected d2406291483775ecddaee929231a39c70c08fda2 da139948aeda677ac09cc0e7d837f8a314de7d55 git | Not specified |
| CNA | Linux | Linux | affected d2406291483775ecddaee929231a39c70c08fda2 64c37e134b120fb462fb4a80694bfb8e7be77b14 git | Not specified |
| CNA | Linux | Linux | affected 6.8 | Not specified |
| CNA | Linux | Linux | unaffected 6.8 semver | Not specified |
| CNA | Linux | Linux | unaffected 6.12.83 6.12.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.13.2 6.13.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.14 * original_commit_for_fix | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| git.kernel.org/stable/c/74c2471eb891a7dcb3874b21c106cda75f52be30 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/da139948aeda677ac09cc0e7d837f8a314de7d55 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| git.kernel.org/stable/c/64c37e134b120fb462fb4a80694bfb8e7be77b14 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.