net/sched: cls_bpf: prevent unbounded recursion in offload rollback
Summary
| CVE | CVE-2026-74382 |
|---|---|
| State | PUBLISHED |
| Assigner | Linux |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-08-15 06:22:40 UTC |
| Updated | 2026-08-17 06:19:33 UTC |
| Description | In the Linux kernel, the following vulnerability has been resolved: net/sched: cls_bpf: prevent unbounded recursion in offload rollback Quan Sun reported [1] a stack overflow in cls_bpf_offload_cmd(). Reproducer on netdevsim: add a skip_sw cls_bpf filter, set the bpf_tc_accept debugfs knob to 0, then `tc filter replace`. The replace calls tc_setup_cb_replace() which fails. cls_bpf_offload_cmd() then swaps prog/oldprog and recursively calls itself to roll back. But bpf_tc_accept=0 makes the rollback fail too, which triggers yet another rollback frame with the same arguments, and so on until the stack is exhausted. bpf_tc_accept is just a convenient knob for the reproducer. Any driver whose tc_setup_cb_replace() fails twice in a row can hit the same loop, so this is not a netdevsim-only issue. Two ways to fix it: 1) Have the rollback call tc_setup_cb_add() on oldprog instead of re-entering cls_bpf_offload_cmd(). 2) Mark the rollback frame with a flag and skip a second-level rollback from inside it. Go with (2). It is the smaller change and keeps the original behaviour: the rollback still goes through tc_setup_cb_replace(), so the driver gets one real chance to restore its state. If that attempt also fails, we just return the original error instead of recursing. [1]: https://lore.kernel.org/bpf/[email protected]/T/#u |
Risk And Classification
EPSS: 0.001950000 probability, percentile 0.095310000 (date 2026-08-17)
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Linux | Linux | affected 102740bd9436a3a6ba129af3a48271d794009fa5 a018f208ab7512380bd4cf670064d48cba00a1b1 git | Not specified |
| CNA | Linux | Linux | affected 102740bd9436a3a6ba129af3a48271d794009fa5 33373e1f378a501bc51aa73312f74295c84e3101 git | Not specified |
| CNA | Linux | Linux | affected 102740bd9436a3a6ba129af3a48271d794009fa5 e2d3b7bab3748c811dc5750ce9a8d62bc7f90ed7 git | Not specified |
| CNA | Linux | Linux | affected 102740bd9436a3a6ba129af3a48271d794009fa5 4a76953c3ed043797e81529b9395e9ca6f4c7609 git | Not specified |
| CNA | Linux | Linux | affected 102740bd9436a3a6ba129af3a48271d794009fa5 1387f252a242a51bfbb6eace29c8f8db21b457da git | Not specified |
| CNA | Linux | Linux | affected 102740bd9436a3a6ba129af3a48271d794009fa5 10753da2d659dd425a6e620f47f86852d604f67f git | Not specified |
| CNA | Linux | Linux | affected 102740bd9436a3a6ba129af3a48271d794009fa5 3fa6fb5d771c992ebedbfa7331c6bcc6f33f89b7 git | Not specified |
| CNA | Linux | Linux | affected 102740bd9436a3a6ba129af3a48271d794009fa5 27db54b90bcc7c37867fe664107fa25ea6a116e4 git | Not specified |
| CNA | Linux | Linux | affected 4.15 | Not specified |
| CNA | Linux | Linux | unaffected 4.15 semver | Not specified |
| CNA | Linux | Linux | unaffected 5.10.261 5.10.* semver | Not specified |
| CNA | Linux | Linux | unaffected 5.15.212 5.15.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.1.178 6.1.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.6.145 6.6.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.12.97 6.12.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.18.40 6.18.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.1.5 7.1.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.2 * original_commit_for_fix | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| git.kernel.org/stable/c/a018f208ab7512380bd4cf670064d48cba00a1b1 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/e2d3b7bab3748c811dc5750ce9a8d62bc7f90ed7 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/3fa6fb5d771c992ebedbfa7331c6bcc6f33f89b7 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/27db54b90bcc7c37867fe664107fa25ea6a116e4 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/4a76953c3ed043797e81529b9395e9ca6f4c7609 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/1387f252a242a51bfbb6eace29c8f8db21b457da | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/33373e1f378a501bc51aa73312f74295c84e3101 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/10753da2d659dd425a6e620f47f86852d604f67f | 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.