net: bcmgenet: unshare the skb before writing the control block
Summary
| CVE | CVE-2026-99192 |
|---|---|
| State | PUBLISHED |
| Assigner | Linux |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-10-28 11:17:40 UTC |
| Updated | 2026-10-30 13:21:52 UTC |
| Description | In the Linux kernel, the following vulnerability has been resolved: net: bcmgenet: unshare the skb before writing the control block bcmgenet stores first_cb, last_cb and bytes_sent in the skb control block and reads them back on completion to free the skb and credit BQL. ether_setup() leaves IFF_TX_SKB_SHARING set, so the stack can resubmit a shared skb that is still in the ring. The next transmit overwrites last_cb, so the earlier slots complete without crediting their bytes and BQL stalls the queue until the watchdog resets it. Unshare the skb before writing the control block. Reproduce with pktgen in clone_skb mode, which hands the driver the same skb while earlier copies are still in the ring: modprobe pktgen pg=/proc/net/pktgen echo "add_device eth0" > $pg/kpktgend_0 echo "dst_mac AA:BB:CC:DD:EE:FF" > $pg/eth0 echo "dst 192.0.2.1" > $pg/eth0 echo "clone_skb 8" > $pg/eth0 echo "count 0" > $pg/eth0 echo start > $pg/pgctrl & sleep 5 echo stop > $pg/pgctrl wait cat /sys/class/net/eth0/queues/tx-0/byte_queue_limits/inflight inflight stays nonzero on the now idle queue. clone_skb 0 leaves it at zero. |
Risk And Classification
EPSS: 0.001790000 probability, percentile 0.074770000 (date 2026-11-01)
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Linux | Linux | affected f48bed16a756f5bc0244acd581f61968f7d7c2a4 c13d43c92bc89f494592a60e624a7c0c42218d36 git | Not specified |
| CNA | Linux | Linux | affected f48bed16a756f5bc0244acd581f61968f7d7c2a4 e5aa07c62e4fda1206d314c9ea36d67cd6b95cad git | Not specified |
| CNA | Linux | Linux | affected f48bed16a756f5bc0244acd581f61968f7d7c2a4 2e5fb9dd3aca0da534793ad8123b81deff396efe git | Not specified |
| CNA | Linux | Linux | affected f48bed16a756f5bc0244acd581f61968f7d7c2a4 40c04abcbc34e3afe338f41dae851ecbd72852ac git | Not specified |
| CNA | Linux | Linux | affected f48bed16a756f5bc0244acd581f61968f7d7c2a4 7939ad3b4db9eadf45a64f0524f38337a9494672 git | Not specified |
| CNA | Linux | Linux | affected f48bed16a756f5bc0244acd581f61968f7d7c2a4 89771ce4f8f67dcffae561b2ccac95c0f6e3aa01 git | Not specified |
| CNA | Linux | Linux | affected fb4ca2b4bc6712a6ad635df5b9b41131846589f9 git | Not specified |
| CNA | Linux | Linux | affected 3.16.50 3.17 semver | Not specified |
| CNA | Linux | Linux | affected 4.13 | Not specified |
| CNA | Linux | Linux | unaffected 4.13 semver | Not specified |
| CNA | Linux | Linux | unaffected 6.1.191 6.1.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.6.161 6.6.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.12.115 6.12.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.18.59 6.18.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.2.13 7.2.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.3 * original_commit_for_fix | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| git.kernel.org/stable/c/40c04abcbc34e3afe338f41dae851ecbd72852ac | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/2e5fb9dd3aca0da534793ad8123b81deff396efe | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/e5aa07c62e4fda1206d314c9ea36d67cd6b95cad | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/89771ce4f8f67dcffae561b2ccac95c0f6e3aa01 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/7939ad3b4db9eadf45a64f0524f38337a9494672 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/c13d43c92bc89f494592a60e624a7c0c42218d36 | 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.