arm64: io: Reject non-user protection in ioremap_prot()
In the Linux kernel, the following vulnerability has been resolved: arm64: io: Reject non-user protection in ioremap_prot() Mapping a stack-top page via /dev/mem with PROT_NONE and then reading that process's /proc//cmdline triggers a spurious WARN in ioremap_prot() through generic_access_phys(): WARNING: ./arch/arm64/include/asm/io.h:275 at generic_access_phys Call trace: generic_access_phys+0x1c8/0x228 (P) __access_remote_vm+0x2b4/0x398 access_remote_vm+0x14/0x30 get_mm_cmdline+0xf8/0x2a0 proc_pid_cmdline_read+0x68/0x120 generic_access_phys() passes the protection derived from the user PTE to ioremap_prot(). On arm64, a PROT_NONE mapping is represented by a present-invalid PTE, so pte_present() still returns true and the protection reaches ioremap_prot(). A PROT_NONE mapping does not have PTE_USER, causing the existing WARN_ON_ONCE() in ioremap_prot() to fire even though this is a valid user mapping. Execute-only mappings have the same issue and must not be readable through this path either. ioremap_prot() should therefore reject protection values without PTE_USER without warning. This makes the access fail cleanly for PROT_NONE and execute-only mappings while retaining the existing user-protection contract.
CVE-2026-98923
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-98923
Linux
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Linux
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "64858b76ec67c5fc40fef8ec1841fecb78c1ebde",
"lessThan": "fddc90d4af4550af410f52d11bbf6b5f36443838",
"versionType": "git"
},
{
"status": "affected",
"version": "eeecafce5afffb4da703666ebefbd4d6e2a5abf6",
"lessThan": "0b04af3d88bb7fc69b2d92457890608860e42365",
"versionType": "git"
},
{
"status": "affected",
"version": "3d64dcc0799c2d6921ba027716b7be721eb19fa8",
"lessThan": "b17aa4955e3a694c663ebe99626e4c76ca4f7cfb",
"versionType": "git"
},
{
"status": "affected",
"version": "8f098037139b294050053123ab2bc0f819d08932",
"lessThan": "9b583795feb51f8d50203228d001760d1344ef01",
"versionType": "git"
},
{
"status": "affected",
"version": "8f098037139b294050053123ab2bc0f819d08932",
"lessThan": "bb756b11ad63832ebee58caf9e8f9381eaecff9f",
"versionType": "git"
},
{
"status": "affected",
"version": "d1ad8fe7f72d73e1617bac79f2ec7a3bedf47e2a",
"versionType": "git"
},
{
"status": "affected",
"version": "6.6.143",
"lessThan": "6.6.158",
"versionType": "semver"
},
{
"status": "affected",
"version": "6.12.93",
"lessThan": "6.12.112",
"versionType": "semver"
},
{
"status": "affected",
"version": "6.18.17",
"lessThan": "6.18.55",
"versionType": "semver"
},
{
"status": "affected",
"version": "6.19.7",
"lessThan": "6.20",
"versionType": "semver"
}
],
"programFiles": [
"arch/arm64/include/asm/io.h"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "7.0"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "7.0",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.6.158",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.112",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.55",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.2.9",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"arch/arm64/include/asm/io.h"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-98923
Source reference:
/cveMetadata/cveId
Publisher severity
No explicit severity was provided.
- Event
- #52784 · Revision 1
- Added to Heist Feed
- Publisher date