CVE-2026-98800 (GCVE-0-2026-98800)
Vulnerability from cvelistv5
Published
2026-10-18 15:48
Modified
2026-10-19 09:25
Severity ?
VLAI Severity ?
EPSS score ?
Summary
In the Linux kernel, the following vulnerability has been resolved:
bpf: Wait for an RCU tasks grace period before freeing trampoline progs
When a prog is detached from a trampoline, it is freed after an RCU
grace period, or an RCU tasks trace one if it is sleepable. This covers
the tasks that are running the prog, since the prog's enter helper takes
the matching read lock before the prog is called. On a preemptible
kernel, it doesn't cover a task that was preempted in the trampoline
just before the enter helper. That task holds no lock yet, and it calls
the prog after it was freed:
BUG: KASAN: vmalloc-out-of-bounds in __bpf_prog_enter_recur+0x3a5/0x3f0
Read of size 8 at addr ffffc90000055040 by task candidate/110
CPU: 1 UID: 0 PID: 110 Comm: candidate Not tainted 7.3.0-rc2-00014-g15071f2a1263-dirty #2 PREEMPT(full)
Call Trace:
<TASK>
__bpf_prog_enter_recur+0x3a5/0x3f0
bpf_trampoline_6442509193+0x37/0xf1
__x64_sys_futex+0x9/0x410
do_syscall_64+0xb0/0x530
...
Wait for an RCU tasks grace period before the existing one when freeing
a prog that was linked to a trampoline. An RCU tasks grace period only
ends once the tasks that were preempted have run again, and
bpf_tramp_image_put() already relies on it to free the image. It doesn't
wait for tasks that sleep in the trampoline, the next commit takes care
of those.
Only progs that were linked to a trampoline can be called this way, so
bpf_trampoline_add_prog() marks them and other progs are still freed as
before.
References
Impacted products
{
"containers": {
"cna": {
"affected": [
{
"defaultStatus": "unaffected",
"product": "Linux",
"programFiles": [
"include/linux/bpf.h",
"kernel/bpf/syscall.c",
"kernel/bpf/trampoline.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"lessThan": "40955f6512a03f0e046f5256b0706b26ba191018",
"status": "affected",
"version": "e21aa341785c679dd409c8cb71f864c00fe6c463",
"versionType": "git"
},
{
"lessThan": "0fb5751a6e411b1b466c06e50021818d9391df98",
"status": "affected",
"version": "e21aa341785c679dd409c8cb71f864c00fe6c463",
"versionType": "git"
},
{
"status": "affected",
"version": "e21d2b92354b3cd25dd774ebb0f0e52ff04a7861",
"versionType": "git"
},
{
"status": "affected",
"version": "85d177f56e5256e14b74a65940f981f6e3e8bb32",
"versionType": "git"
},
{
"lessThan": "5.11",
"status": "affected",
"version": "5.10.28",
"versionType": "semver"
},
{
"lessThan": "5.12",
"status": "affected",
"version": "5.11.11",
"versionType": "semver"
}
]
},
{
"defaultStatus": "affected",
"product": "Linux",
"programFiles": [
"include/linux/bpf.h",
"kernel/bpf/syscall.c",
"kernel/bpf/trampoline.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"status": "affected",
"version": "5.12"
},
{
"lessThan": "5.12",
"status": "unaffected",
"version": "0",
"versionType": "semver"
},
{
"lessThanOrEqual": "7.2.*",
"status": "unaffected",
"version": "7.2.10",
"versionType": "semver"
},
{
"lessThanOrEqual": "*",
"status": "unaffected",
"version": "7.3",
"versionType": "original_commit_for_fix"
}
]
}
],
"cpeApplicability": [
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "7.2.10",
"versionStartIncluding": "5.12",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "7.3",
"versionStartIncluding": "5.12",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "5.10.28",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "5.11.11",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Wait for an RCU tasks grace period before freeing trampoline progs\n\nWhen a prog is detached from a trampoline, it is freed after an RCU\ngrace period, or an RCU tasks trace one if it is sleepable. This covers\nthe tasks that are running the prog, since the prog\u0027s enter helper takes\nthe matching read lock before the prog is called. On a preemptible\nkernel, it doesn\u0027t cover a task that was preempted in the trampoline\njust before the enter helper. That task holds no lock yet, and it calls\nthe prog after it was freed:\n\n BUG: KASAN: vmalloc-out-of-bounds in __bpf_prog_enter_recur+0x3a5/0x3f0\n Read of size 8 at addr ffffc90000055040 by task candidate/110\n CPU: 1 UID: 0 PID: 110 Comm: candidate Not tainted 7.3.0-rc2-00014-g15071f2a1263-dirty #2 PREEMPT(full)\n Call Trace:\n \u003cTASK\u003e\n __bpf_prog_enter_recur+0x3a5/0x3f0\n bpf_trampoline_6442509193+0x37/0xf1\n __x64_sys_futex+0x9/0x410\n do_syscall_64+0xb0/0x530\n ...\n\nWait for an RCU tasks grace period before the existing one when freeing\na prog that was linked to a trampoline. An RCU tasks grace period only\nends once the tasks that were preempted have run again, and\nbpf_tramp_image_put() already relies on it to free the image. It doesn\u0027t\nwait for tasks that sleep in the trampoline, the next commit takes care\nof those.\n\nOnly progs that were linked to a trampoline can be called this way, so\nbpf_trampoline_add_prog() marks them and other progs are still freed as\nbefore."
}
],
"providerMetadata": {
"dateUpdated": "2026-10-19T09:25:53.724Z",
"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"shortName": "Linux"
},
"references": [
{
"url": "https://git.kernel.org/stable/c/40955f6512a03f0e046f5256b0706b26ba191018"
},
{
"url": "https://git.kernel.org/stable/c/0fb5751a6e411b1b466c06e50021818d9391df98"
}
],
"title": "bpf: Wait for an RCU tasks grace period before freeing trampoline progs",
"x_generator": {
"engine": "bippy-1.2.0"
}
}
},
"cveMetadata": {
"assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"assignerShortName": "Linux",
"cveId": "CVE-2026-98800",
"datePublished": "2026-10-18T15:48:46.223Z",
"dateReserved": "2026-09-25T10:25:14.370Z",
"dateUpdated": "2026-10-19T09:25:53.724Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
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