GHSA-XQP7-9GQV-6978
Vulnerability from github – Published: 2026-03-25 12:30 – Updated: 2026-03-25 12:30In the Linux kernel, the following vulnerability has been resolved:
arm64: io: Extract user memory type in ioremap_prot()
The only caller of ioremap_prot() outside of the generic ioremap() implementation is generic_access_phys(), which passes a 'pgprot_t' value determined from the user mapping of the target 'pfn' being accessed by the kernel. On arm64, the 'pgprot_t' contains all of the non-address bits from the pte, including the permission controls, and so we end up returning a new user mapping from ioremap_prot() which faults when accessed from the kernel on systems with PAN:
| Unable to handle kernel read from unreadable memory at virtual address ffff80008ea89000 | ... | Call trace: | __memcpy_fromio+0x80/0xf8 | generic_access_phys+0x20c/0x2b8 | __access_remote_vm+0x46c/0x5b8 | access_remote_vm+0x18/0x30 | environ_read+0x238/0x3e8 | vfs_read+0xe4/0x2b0 | ksys_read+0xcc/0x178 | __arm64_sys_read+0x4c/0x68
Extract only the memory type from the user 'pgprot_t' in ioremap_prot() and assert that we're being passed a user mapping, to protect us against any changes in future that may require additional handling. To avoid falsely flagging users of ioremap(), provide our own ioremap() macro which simply wraps __ioremap_prot().
{
"affected": [],
"aliases": [
"CVE-2026-23346"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-03-25T11:16:32Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\narm64: io: Extract user memory type in ioremap_prot()\n\nThe only caller of ioremap_prot() outside of the generic ioremap()\nimplementation is generic_access_phys(), which passes a \u0027pgprot_t\u0027 value\ndetermined from the user mapping of the target \u0027pfn\u0027 being accessed by\nthe kernel. On arm64, the \u0027pgprot_t\u0027 contains all of the non-address\nbits from the pte, including the permission controls, and so we end up\nreturning a new user mapping from ioremap_prot() which faults when\naccessed from the kernel on systems with PAN:\n\n | Unable to handle kernel read from unreadable memory at virtual address ffff80008ea89000\n | ...\n | Call trace:\n | __memcpy_fromio+0x80/0xf8\n | generic_access_phys+0x20c/0x2b8\n | __access_remote_vm+0x46c/0x5b8\n | access_remote_vm+0x18/0x30\n | environ_read+0x238/0x3e8\n | vfs_read+0xe4/0x2b0\n | ksys_read+0xcc/0x178\n | __arm64_sys_read+0x4c/0x68\n\nExtract only the memory type from the user \u0027pgprot_t\u0027 in ioremap_prot()\nand assert that we\u0027re being passed a user mapping, to protect us against\nany changes in future that may require additional handling. To avoid\nfalsely flagging users of ioremap(), provide our own ioremap() macro\nwhich simply wraps __ioremap_prot().",
"id": "GHSA-xqp7-9gqv-6978",
"modified": "2026-03-25T12:30:23Z",
"published": "2026-03-25T12:30:23Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-23346"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/3d64dcc0799c2d6921ba027716b7be721eb19fa8"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/8f098037139b294050053123ab2bc0f819d08932"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/d1ad8fe7f72d73e1617bac79f2ec7a3bedf47e2a"
}
],
"schema_version": "1.4.0",
"severity": []
}
Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.