KEYS: trusted: Fix TPM teardown ordering
In the Linux kernel, the following vulnerability has been resolved: KEYS: trusted: Fix TPM teardown ordering trusted_tpm_exit() drops the TPM chip reference and frees the digest array before unregistering the trusted key type. key_type_lookup() holds key_types_sem for reading until the key operation finishes, while unregister_key_type() takes it for writing. It therefore provides the synchronization point that must precede backend teardown. The current order permits this interleaving: CPU 0 CPU 1 trusted_tpm_exit() key_type_lookup("trusted") put_device(&chip->dev) trusted_tpm_seal() kfree(digests) pcrlock() unregister_key_type() tpm_pcr_extend(..., digests) CPU 1 can consequently dereference the freed digest array. The chip can also be released before callbacks stop using it. KASAN reported: BUG: KASAN: slab-use-after-free in tpm_pcr_extend+0x1f0/0x200 Read of size 2 at addr ffff88810872d000 by task poc/89 Call Trace: tpm_pcr_extend+0x1f0/0x200 pcrlock+0x42/0x70 [trusted] trusted_tpm_seal+0x1b6/0x570 [trusted] trusted_instantiate+0x293/0x340 [trusted] __key_instantiate_and_link+0xb2/0x2b0 __key_create_or_update+0x61e/0xb50 __do_sys_add_key+0x1b8/0x310 Allocated by task 88: __kmalloc_noprof+0x1a7/0x490 do_one_initcall+0xa1/0x390 do_init_module+0x2df/0x840 Freed by task 90: kfree+0x131/0x3c0 trusted_tpm_exit+0x59/0xa0 [trusted] __do_sys_delete_module+0x346/0x510 Move unregister_key_type() before releasing either resource. This stops new lookups and waits for in-flight key opera
CVE-2026-89763
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-2026-89763
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": "0b6cf6b97b7ef1fa3c7fefab0cac897a1c4a3400",
"lessThan": "81dfc6c665547a4e41721b6716f894f263a5e03f",
"versionType": "git"
},
{
"status": "affected",
"version": "0b6cf6b97b7ef1fa3c7fefab0cac897a1c4a3400",
"lessThan": "3d67b4acbfc7af331d887a8efc04bef6573b8a7a",
"versionType": "git"
},
{
"status": "affected",
"version": "0b6cf6b97b7ef1fa3c7fefab0cac897a1c4a3400",
"lessThan": "753c978f2400f9783eb524842a975d3ac950d511",
"versionType": "git"
},
{
"status": "affected",
"version": "0b6cf6b97b7ef1fa3c7fefab0cac897a1c4a3400",
"lessThan": "2f7541afbc57fe9d26769a22c31d8ce8790c9a19",
"versionType": "git"
},
{
"status": "affected",
"version": "0b6cf6b97b7ef1fa3c7fefab0cac897a1c4a3400",
"lessThan": "5e2d672280d97d83de43031d93761b12dadd7b8a",
"versionType": "git"
}
],
"programFiles": [
"security/keys/trusted-keys/trusted_tpm1.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "5.1"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "5.1",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.6.160",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.111",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.50",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.2.4",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"security/keys/trusted-keys/trusted_tpm1.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-89763
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #46724 · Revision 1
- Added to Heist Feed
- Publisher date