tracepoint: balance regfunc() on func_add() failure in tracepoint_add_func()
Published May 28, 2026
5.5
MEDIUMCVSS 3.1
EPSS 0.16%
Description
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.
Affected products
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- Version StatusaffectedConstraints
- Version StatusaffectedConstraints
- Version StatusaffectedConstraints
- Version StatusaffectedConstraints
- Version StatusaffectedConstraints
- Version StatusaffectedConstraints
- Version StatusaffectedConstraints
- Version StatusaffectedConstraints
- Version
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- Version 4.10StatusaffectedConstraints-
- Version 0StatusunaffectedConstraints<4.10
- Version 5.10.259StatusunaffectedConstraints<=5.10.*
- Version 5.15.210StatusunaffectedConstraints<=5.15.*
- Version 6.1.176StatusunaffectedConstraints<=6.1.*
- Version 6.12.88StatusunaffectedConstraints<=6.12.*
- Version 6.18.30StatusunaffectedConstraints<=6.18.*
- Version 6.6.140StatusunaffectedConstraints<=6.6.*
- Version 7.0.7StatusunaffectedConstraints<=7.0.*
- Version 7.1StatusunaffectedConstraints<=*
- Version
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | |||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Linux | Linux | unaffected |
| |||||||||||||||||||||||||||||||||
| Linux | Linux | affected |
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- ≥ 4.10 · < 6.6.140
- ≥ 6.7 · < 6.12.88
- ≥ 6.13 · < 6.18.30
- ≥ 6.19 · < 7.0.7
No data.
Red Hat Enterprise Linux 10
kernel
Fix deferred
Red Hat Enterprise Linux 6
kernel
Not affected
Red Hat Enterprise Linux 7
kernel
Not affected
Red Hat Enterprise Linux 7
kernel-rt
Not affected
Red Hat Enterprise Linux 8
kernel
Fix deferred
Red Hat Enterprise Linux 8
kernel-rt
Fix deferred
Red Hat Enterprise Linux 9
kernel
Fix deferred
Red Hat Enterprise Linux 9
kernel-rt
Fix deferred
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 10 | kernel | Fix deferred | n/a |
| Red Hat Enterprise Linux 6 | kernel | Not affected | n/a |
| Red Hat Enterprise Linux 7 | kernel | Not affected | n/a |
| Red Hat Enterprise Linux 7 | kernel-rt | Not affected | n/a |
| Red Hat Enterprise Linux 8 | kernel | Fix deferred | n/a |
| Red Hat Enterprise Linux 8 | kernel-rt | Fix deferred | n/a |
| Red Hat Enterprise Linux 9 | kernel | Fix deferred | n/a |
| Red Hat Enterprise Linux 9 | kernel-rt | Fix deferred | n/a |
No package ranges for this CVE.
Remediation
No remediation recorded yet.
References (14)
- https://access.redhat.com/security/cve/CVE-2026-46196 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=2482590 Issue Tracking
- https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-32823 Advisory
- https://git.kernel.org/stable/c/247ed8a969f981bfba3112fd4bb441eaa6cef59c Patch
- https://git.kernel.org/stable/c/2c5b8eeea006eb694c81631cd5713d494b80be90 Patch
- https://git.kernel.org/stable/c/342829e042ac00f3d68d442ea92873fb6683f494 Patch
- https://git.kernel.org/stable/c/36ff362235307af95152d510b53c2d9b8773a342
- https://git.kernel.org/stable/c/4f1756d043e56ea2e9a6c858fb290a0cf6fc2251
- https://git.kernel.org/stable/c/5787052e5f69beb649f3d6a80a8aa37d9e683e4e
- https://git.kernel.org/stable/c/7bcadb3c2bc1cf60690e931aadd35fb7bd646a49 Patch
- https://git.kernel.org/stable/c/fad217e16fded7f3c09f8637b0f6a224d58b5f2e Patch
- https://lore.kernel.org/linux-cve-announce/2026052833-CVE-2026-46196-8c55@gregkh/T
- https://nvd.nist.gov/vuln/detail/CVE-2026-46196
- https://www.cve.org/CVERecord?id=CVE-2026-46196
Change history (0)
No recorded changes yet.