CVE-2026-43371

Description

In the Linux kernel, the following vulnerability has been resolved: net: macb: Shuffle the tx ring before enabling tx Quanyang observed that when using an NFS rootfs on an AMD ZynqMp board, the rootfs may take an extended time to recover after a suspend. Upon investigation, it was determined that the issue originates from a problem in the macb driver. According to the Zynq UltraScale TRM [1], when transmit is disabled, the transmit buffer queue pointer resets to point to the address specified by the transmit buffer queue base address register. In the current implementation, the code merely resets `queue->tx_head` and `queue->tx_tail` to '0'. This approach presents several issues: - Packets already queued in the tx ring are silently lost, leading to memory leaks since the associated skbs cannot be released. - Concurrent write access to `queue->tx_head` and `queue->tx_tail` may occur from `macb_tx_poll()` or `macb_start_xmit()` when these values are reset to '0'. - The transmission may become stuck on a packet that has already been sent out, with its 'TX_USED' bit set, but has not yet been processed. However, due to the manipulation of 'queue->tx_head' and 'queue->tx_tail', `macb_tx_poll()` incorrectly assumes there are no packets to handle because `queue->tx_head == queue->tx_tail`. This issue is only resolved when a new packet is placed at this position. This is the root cause of the prolonged recovery time observed for the NFS root filesystem. To resolve this issue, shuffle the tx ring and tx skb array so that the first unsent packet is positioned at the start of the tx ring. Additionally, ensure that updates to `queue->tx_head` and `queue->tx_tail` are properly protected with the appropriate lock. [1] https://docs.amd.com/v/u/en-US/ug1085-zynq-ultrascale-trm

Gravité et risque d'exploitation

CVE-2026-43371 obtient un score CVSS de 0.0/10, soit une gravité non évaluée. Selon le modèle EPSS, la probabilité qu'elle soit exploitée dans les 30 prochains jours est de 0.16 %, ce qui la place devant 5.1 % des CVE référencées.

Que faire ?

• Vérifiez si Linux (versions b3a7aa33ca7d46be513fccf832d3540acfe587d0, 6e704e89f16fd4a1145756210bc210f14f174f94, 6.1.165, 6.12.75, <6.12.78, <6.6.130, <c6783bfa31a59f34fe4feb1bdbf67791ef3fb0b7, ec4445ae9e58aed88561d3d1dfa849b039c7782e, <403182e0771b250cfde0fe7e1081d095ceaf8230, bf9cf80cab81e39701861a42877a28295ade266f, <6.18.20, <6.1.167, 316d9fe71fb18bc9b1dba464fdb68dd201315eba, 6.19.6, 6.6.128, <88f974fe118cb4653f029929ecbca7cfe06132ae, <6.19.9, d89b8b17057e16fad4564c71160e68ca549c1b42, 6.18.16, <881a0263d502e1a93ebc13a78254e9ad19520232, <0a47c3889fcd843c72aa57fa8c4d06f5801fced4, <58f5d34f88e8f00910b692537f7b2efdb8c3705d) est présent sur votre parc.
• Appliquez le correctif ou la version corrigée indiqués dans les références de l'éditeur.
• À défaut de correctif, limitez l'exposition (filtrage réseau, désactivation du composant).
• Automatisez la détection : les agents CVE Heimdall (gratuits, open source) corrèlent l'inventaire de vos serveurs avec la base CVE.

Références

• https://git.kernel.org/stable/c/c6783bfa31a59f34fe4feb1bdbf67791ef3fb0b7
• https://git.kernel.org/stable/c/0a47c3889fcd843c72aa57fa8c4d06f5801fced4
• https://git.kernel.org/stable/c/88f974fe118cb4653f029929ecbca7cfe06132ae
• https://git.kernel.org/stable/c/58f5d34f88e8f00910b692537f7b2efdb8c3705d
• https://git.kernel.org/stable/c/403182e0771b250cfde0fe7e1081d095ceaf8230
• https://git.kernel.org/stable/c/881a0263d502e1a93ebc13a78254e9ad19520232