---
id: CVE-2022-50080
title: 'tee: add overflow check in register_shm_helper()'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  tee: add overflow check in register_shm_helper()

  With special lengths supplied by user space, register_shm_helper() has
  an integer overflow when calculating the number…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 033ddf12bcf5326b93bd604f50a7474a434a35f9 <
    b37e0f17653c00b586cdbcdf0dbca475358ecffd
  - >-
    Linux >= 033ddf12bcf5326b93bd604f50a7474a434a35f9 <
    965333345fe952cc7eebc8e3a565ffc709441af2
  - >-
    Linux >= 033ddf12bcf5326b93bd604f50a7474a434a35f9 <
    578c349570d2a912401963783b36e0ec7a25c053
  - >-
    Linux >= 033ddf12bcf5326b93bd604f50a7474a434a35f9 <
    c12f0e6126ad223806a365084e86370511654bf1
  - >-
    Linux >= 033ddf12bcf5326b93bd604f50a7474a434a35f9 <
    2f8e79a1a6128214cb9b205a9869341af5dfb16b
  - >-
    Linux >= 033ddf12bcf5326b93bd604f50a7474a434a35f9 <
    58c008d4d398f792ca67f35650610864725518fd
  - >-
    Linux >= 033ddf12bcf5326b93bd604f50a7474a434a35f9 <
    573ae4f13f630d6660008f1974c0a8a29c30e18a
  - Linux 4.16
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-11-05T19:54:05.265629Z'
published: '2025-06-18'
updated: '2026-11-05'
sourceUpdated: '2026-11-05T20:00:16.141Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2022-50080'
references:
  - url: 'https://git.kernel.org/stable/c/b37e0f17653c00b586cdbcdf0dbca475358ecffd'
  - url: 'https://git.kernel.org/stable/c/965333345fe952cc7eebc8e3a565ffc709441af2'
  - url: 'https://git.kernel.org/stable/c/578c349570d2a912401963783b36e0ec7a25c053'
  - url: 'https://git.kernel.org/stable/c/c12f0e6126ad223806a365084e86370511654bf1'
  - url: 'https://git.kernel.org/stable/c/2f8e79a1a6128214cb9b205a9869341af5dfb16b'
  - url: 'https://git.kernel.org/stable/c/58c008d4d398f792ca67f35650610864725518fd'
  - url: 'https://git.kernel.org/stable/c/573ae4f13f630d6660008f1974c0a8a29c30e18a'
tags:
  - cve.org
epss: 0.00268
epssPercentile: 0.19072
ingestedAt: '2026-11-05T22:38:31.646Z'
---

## Overview

In the Linux kernel, the following vulnerability has been resolved:

tee: add overflow check in register_shm_helper()

With special lengths supplied by user space, register_shm_helper() has
an integer overflow when calculating the number of pages covered by a
supplied user space memory region.

This causes internal_get_user_pages_fast() a helper function of
pin_user_pages_fast() to do a NULL pointer dereference:

  Unable to handle kernel NULL pointer dereference at virtual address 0000000000000010
  Modules linked in:
  CPU: 1 PID: 173 Comm: optee_example_a Not tainted 5.19.0 #11
  Hardware name: QEMU QEMU Virtual Machine, BIOS 0.0.0 02/06/2015
  pc : internal_get_user_pages_fast+0x474/0xa80
  Call trace:
   internal_get_user_pages_fast+0x474/0xa80
   pin_user_pages_fast+0x24/0x4c
   register_shm_helper+0x194/0x330
   tee_shm_register_user_buf+0x78/0x120
   tee_ioctl+0xd0/0x11a0
   __arm64_sys_ioctl+0xa8/0xec
   invoke_syscall+0x48/0x114

Fix this by adding an an explicit call to access_ok() in
tee_shm_register_user_buf() to catch an invalid user space address
early.

## Affected

- `Linux >= 033ddf12bcf5326b93bd604f50a7474a434a35f9 < b37e0f17653c00b586cdbcdf0dbca475358ecffd`
- `Linux >= 033ddf12bcf5326b93bd604f50a7474a434a35f9 < 965333345fe952cc7eebc8e3a565ffc709441af2`
- `Linux >= 033ddf12bcf5326b93bd604f50a7474a434a35f9 < 578c349570d2a912401963783b36e0ec7a25c053`
- `Linux >= 033ddf12bcf5326b93bd604f50a7474a434a35f9 < c12f0e6126ad223806a365084e86370511654bf1`
- `Linux >= 033ddf12bcf5326b93bd604f50a7474a434a35f9 < 2f8e79a1a6128214cb9b205a9869341af5dfb16b`
- `Linux >= 033ddf12bcf5326b93bd604f50a7474a434a35f9 < 58c008d4d398f792ca67f35650610864725518fd`
- `Linux >= 033ddf12bcf5326b93bd604f50a7474a434a35f9 < 573ae4f13f630d6660008f1974c0a8a29c30e18a`
- `Linux 4.16`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.