binder: fix use-after-free in shinker's callback
Summary
| CVE | CVE-2023-52438 |
|---|---|
| State | PUBLISHED |
| Assigner | Linux |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2024-02-20 21:15:08 UTC |
| Updated | 2026-08-04 10:18:27 UTC |
| Description | In the Linux kernel, the following vulnerability has been resolved: binder: fix use-after-free in shinker's callback The mmap read lock is used during the shrinker's callback, which means that using alloc->vma pointer isn't safe as it can race with munmap(). As of commit dd2283f2605e ("mm: mmap: zap pages with read mmap_sem in munmap") the mmap lock is downgraded after the vma has been isolated. I was able to reproduce this issue by manually adding some delays and triggering page reclaiming through the shrinker's debug sysfs. The following KASAN report confirms the UAF: ================================================================== BUG: KASAN: slab-use-after-free in zap_page_range_single+0x470/0x4b8 Read of size 8 at addr ffff356ed50e50f0 by task bash/478 CPU: 1 PID: 478 Comm: bash Not tainted 6.6.0-rc5-00055-g1c8b86a3799f-dirty #70 Hardware name: linux,dummy-virt (DT) Call trace: zap_page_range_single+0x470/0x4b8 binder_alloc_free_page+0x608/0xadc __list_lru_walk_one+0x130/0x3b0 list_lru_walk_node+0xc4/0x22c binder_shrink_scan+0x108/0x1dc shrinker_debugfs_scan_write+0x2b4/0x500 full_proxy_write+0xd4/0x140 vfs_write+0x1ac/0x758 ksys_write+0xf0/0x1dc __arm64_sys_write+0x6c/0x9c Allocated by task 492: kmem_cache_alloc+0x130/0x368 vm_area_alloc+0x2c/0x190 mmap_region+0x258/0x18bc do_mmap+0x694/0xa60 vm_mmap_pgoff+0x170/0x29c ksys_mmap_pgoff+0x290/0x3a0 __arm64_sys_mmap+0xcc/0x144 Freed by task 491: kmem_cache_free+0x17c/0x3c8 vm_area_free_rcu_cb+0x74/0x98 rcu_core+0xa38/0x26d4 rcu_core_si+0x10/0x1c __do_softirq+0x2fc/0xd24 Last potentially related work creation: __call_rcu_common.constprop.0+0x6c/0xba0 call_rcu+0x10/0x1c vm_area_free+0x18/0x24 remove_vma+0xe4/0x118 do_vmi_align_munmap.isra.0+0x718/0xb5c do_vmi_munmap+0xdc/0x1fc __vm_munmap+0x10c/0x278 __arm64_sys_munmap+0x58/0x7c Fix this issue by performing instead a vma_lookup() which will fail to find the vma that was isolated before the mmap lock downgrade. Note that this option has better performance than upgrading to a mmap write lock which would increase contention. Plus, mmap_write_trylock() has been recently removed anyway. |
Risk And Classification
Primary CVSS: v3.1 7.8 HIGH from [email protected]
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Problem Types: CWE-416
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | [email protected] | Primary | 7.8 | HIGH | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| 3.1 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | Secondary | 7.8 | HIGH | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| 3.1 | CNA | DECLARED | 7.8 | HIGH | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
CVSS v3.1 Breakdown
Attack Vector
LocalAttack Complexity
LowPrivileges Required
LowUser Interaction
NoneScope
UnchangedConfidentiality
HighIntegrity
HighAvailability
HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/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 dd2283f2605e3b3e9c61bcae844b34f2afa4813f a53e15e592b4dcc91c3a3b8514e484a0bdbc53a3 git | Not specified |
| CNA | Linux | Linux | affected dd2283f2605e3b3e9c61bcae844b34f2afa4813f c8c1158ffb007197f31f9d9170cf13e4f34cbb5c git | Not specified |
| CNA | Linux | Linux | affected dd2283f2605e3b3e9c61bcae844b34f2afa4813f 8ad4d580e8aff8de2a4d57c5930fcc29f1ffd4a6 git | Not specified |
| CNA | Linux | Linux | affected dd2283f2605e3b3e9c61bcae844b34f2afa4813f 9fa04c93f24138747807fe75b5591bb680098f56 git | Not specified |
| CNA | Linux | Linux | affected dd2283f2605e3b3e9c61bcae844b34f2afa4813f a49087ab93508b60d9b8add91707a22dda832869 git | Not specified |
| CNA | Linux | Linux | affected dd2283f2605e3b3e9c61bcae844b34f2afa4813f e074686e993ff1be5f21b085a3b1b4275ccd5727 git | Not specified |
| CNA | Linux | Linux | affected dd2283f2605e3b3e9c61bcae844b34f2afa4813f 3f489c2067c5824528212b0fc18b28d51332d906 git | Not specified |
| CNA | Linux | Linux | affected 4.20 | Not specified |
| CNA | Linux | Linux | unaffected 4.20 semver | Not specified |
| CNA | Linux | Linux | unaffected 5.4.268 5.4.* semver | Not specified |
| CNA | Linux | Linux | unaffected 5.10.209 5.10.* semver | Not specified |
| CNA | Linux | Linux | unaffected 5.15.148 5.15.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.1.74 6.1.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.6.13 6.6.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.7.1 6.7.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.8 * original_commit_for_fix | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| git.kernel.org/stable/c/3f489c2067c5824528212b0fc18b28d51332d906 | af854a3a-2127-422b-91ae-364da2661108 | git.kernel.org | Patch |
| git.kernel.org/stable/c/9fa04c93f24138747807fe75b5591bb680098f56 | af854a3a-2127-422b-91ae-364da2661108 | git.kernel.org | Patch |
| lists.debian.org/debian-lts-announce/2024/06/msg00016.html | af854a3a-2127-422b-91ae-364da2661108 | lists.debian.org | |
| git.kernel.org/stable/c/e074686e993ff1be5f21b085a3b1b4275ccd5727 | af854a3a-2127-422b-91ae-364da2661108 | git.kernel.org | Patch |
| git.kernel.org/stable/c/a53e15e592b4dcc91c3a3b8514e484a0bdbc53a3 | af854a3a-2127-422b-91ae-364da2661108 | git.kernel.org | Patch |
| git.kernel.org/stable/c/c8c1158ffb007197f31f9d9170cf13e4f34cbb5c | af854a3a-2127-422b-91ae-364da2661108 | git.kernel.org | Patch |
| git.kernel.org/stable/c/8ad4d580e8aff8de2a4d57c5930fcc29f1ffd4a6 | af854a3a-2127-422b-91ae-364da2661108 | git.kernel.org | Patch |
| git.kernel.org/stable/c/a49087ab93508b60d9b8add91707a22dda832869 | af854a3a-2127-422b-91ae-364da2661108 | 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.
Legacy QID Mappings
- 200182 Ubuntu Security Notification for Linux kernel (OEM) Vulnerabilities (USN-6688-1)
- 200241 Ubuntu Security Notification for Linux kernel Vulnerabilities (USN-6726-1)
- 200242 Ubuntu Security Notification for Linux kernel Vulnerabilities (USN-6724-1)
- 200243 Ubuntu Security Notification for Linux kernel Vulnerabilities (USN-6725-1)
- 379614 Alibaba Cloud Linux Security Update for cloud-kernel (ALINUX3-SA-2024:0017)