bpf: Reject untrusted allocated-object pointers
In the Linux kernel, the following vulnerability has been resolved: bpf: Reject untrusted allocated-object pointers When the final RCU read-side critical section ends, a local kptr is demoted to PTR_UNTRUSTED but retains MEM_ALLOC. The pointer may be NULL or may refer to an object whose lifetime is no longer protected. type_is_ptr_alloc_obj() nevertheless recognizes any PTR_TO_BTF_ID with MEM_ALLOC as a live allocated object. In particular, a refcount-only local kptr never carries NON_OWN_REF, so it still passes the bpf_refcount_acquire() argument check after RCU protection ends. The kfunc can then dereference NULL or stale memory. Make type_is_ptr_alloc_obj() reject PTR_UNTRUSTED pointers. Since type_is_non_owning_ref() is based on the same predicate, graph kfunc arguments obey the same live-object requirement. Fault-protected reads of the demoted pointer remain valid: writes are already rejected, and read fixups use bpf_may_fault_on_deref() rather than this predicate. [ kkd: Rewrote commit log ]
CVE-2026-98037
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-2026-98037
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": "1b12171533a9bb23cf6fba7262b479028b65e1e8",
"lessThan": "092c2874dc1b2060fa77a465a971acd4fdf87683",
"versionType": "git"
},
{
"status": "affected",
"version": "1b12171533a9bb23cf6fba7262b479028b65e1e8",
"lessThan": "135d542b97fa93e32c457d49d6e7b33ca7d05bae",
"versionType": "git"
},
{
"status": "affected",
"version": "1b12171533a9bb23cf6fba7262b479028b65e1e8",
"lessThan": "6b1f786ad85a0b63393b76f5e634deab1a73198c",
"versionType": "git"
},
{
"status": "affected",
"version": "1b12171533a9bb23cf6fba7262b479028b65e1e8",
"lessThan": "7441ee8276641bddaf1cba7bb75ef9c1458ceb3b",
"versionType": "git"
}
],
"programFiles": [
"include/linux/bpf_verifier.h"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "6.8"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "6.8",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.12.111",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.53",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.2.7",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"include/linux/bpf_verifier.h"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-98037
Source reference:
/cveMetadata/cveId
Publisher severity
No explicit severity was provided.
- Event
- #38159 · Revision 1
- Added to Heist Feed
- Publisher date