tracepoint: balance regfunc() on func_add() failure in tracepoint_add_func()
Summary
| CVE | CVE-2026-46196 |
|---|---|
| State | PUBLISHED |
| Assigner | Linux |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-05-28 10:16:35 UTC |
| Updated | 2026-05-28 13:44:01 UTC |
| Description | In the Linux kernel, the following vulnerability has been resolved: tracepoint: balance regfunc() on func_add() failure in tracepoint_add_func() When a tracepoint goes through the 0 -> 1 transition, tracepoint_add_func() invokes the subsystem's ext->regfunc() before attempting to install the new probe via func_add(). If func_add() then fails (for example, when allocate_probes() cannot allocate a new probe array under memory pressure and returns -ENOMEM), the function returns the error without calling the matching ext->unregfunc(), leaving the side effects of regfunc() behind with no installed probe to justify them. For syscall tracepoints this is particularly unpleasant: syscall_regfunc() bumps sys_tracepoint_refcount and sets SYSCALL_TRACEPOINT on every task. After a leaked failure, the refcount is stuck at a non-zero value with no consumer, and every task continues paying the syscall trace entry/exit overhead until reboot. Other subsystems providing regfunc()/unregfunc() pairs exhibit similarly scoped persistent state. Mirror the existing 1 -> 0 cleanup and call ext->unregfunc() in the func_add() error path, gated on the same condition used there so the unwind is symmetric with the registration. |
Risk And Classification
EPSS: 0.000180000 probability, percentile 0.050770000 (date 2026-06-01)
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Linux | Linux | affected 8cf868affdc459beee1a941df0cfaba1673740e3 247ed8a969f981bfba3112fd4bb441eaa6cef59c git | Not specified |
| CNA | Linux | Linux | affected 8cf868affdc459beee1a941df0cfaba1673740e3 7bcadb3c2bc1cf60690e931aadd35fb7bd646a49 git | Not specified |
| CNA | Linux | Linux | affected 8cf868affdc459beee1a941df0cfaba1673740e3 2c5b8eeea006eb694c81631cd5713d494b80be90 git | Not specified |
| CNA | Linux | Linux | affected 8cf868affdc459beee1a941df0cfaba1673740e3 342829e042ac00f3d68d442ea92873fb6683f494 git | Not specified |
| CNA | Linux | Linux | affected 8cf868affdc459beee1a941df0cfaba1673740e3 fad217e16fded7f3c09f8637b0f6a224d58b5f2e git | Not specified |
| CNA | Linux | Linux | affected 4.10 | Not specified |
| CNA | Linux | Linux | unaffected 4.10 semver | Not specified |
| CNA | Linux | Linux | unaffected 6.6.140 6.6.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.12.88 6.12.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.18.30 6.18.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.0.7 7.0.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.1-rc1 * original_commit_for_fix | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| git.kernel.org/stable/c/247ed8a969f981bfba3112fd4bb441eaa6cef59c | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/342829e042ac00f3d68d442ea92873fb6683f494 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/fad217e16fded7f3c09f8637b0f6a224d58b5f2e | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/2c5b8eeea006eb694c81631cd5713d494b80be90 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/7bcadb3c2bc1cf60690e931aadd35fb7bd646a49 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.