UBUNTU-CVE-2026-43371
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
02 / AFFECTED SOFTWARE
Affected packages
44 explicit affected versions
4 explicit affected versions
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13 explicit affected versions
37 explicit affected versions
10 explicit affected versions
13 explicit affected versions
12 explicit affected versions
10 explicit affected versions
46 explicit affected versions
46 explicit affected versions
13 explicit affected versions
4 explicit affected versions
1 explicit affected versions
13 explicit affected versions
43 explicit affected versions
7 explicit affected versions
11 explicit affected versions
50 explicit affected versions
6 explicit affected versions
12 explicit affected versions
19 explicit affected versions
10 explicit affected versions
6 explicit affected versions
24 explicit affected versions
10 explicit affected versions
37 explicit affected versions
26 explicit affected versions
7 explicit affected versions
40 explicit affected versions
35 explicit affected versions
18 explicit affected versions
45 explicit affected versions
13 explicit affected versions
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1 explicit affected versions
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16 explicit affected versions
10 explicit affected versions
48 explicit affected versions
8 explicit affected versions
7 explicit affected versions
12 explicit affected versions
11 explicit affected versions
7 explicit affected versions
12 explicit affected versions
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1 explicit affected versions
7 explicit affected versions
17 explicit affected versions
12 explicit affected versions
41 explicit affected versions
16 explicit affected versions
34 explicit affected versions
10 explicit affected versions
39 explicit affected versions
10 explicit affected versions
11 explicit affected versions
26 explicit affected versions
10 explicit affected versions
13 explicit affected versions
29 explicit affected versions
13 explicit affected versions
12 explicit affected versions
41 explicit affected versions
20 explicit affected versions
40 explicit affected versions
33 explicit affected versions
23 explicit affected versions
10 explicit affected versions
19 explicit affected versions
11 explicit affected versions
12 explicit affected versions
7 explicit affected versions
26 explicit affected versions
48 explicit affected versions
11 explicit affected versions
13 explicit affected versions
16 explicit affected versions
50 explicit affected versions
3 explicit affected versions
7 explicit affected versions
51 explicit affected versions
18 explicit affected versions
43 explicit affected versions
12 explicit affected versions
27 explicit affected versions
7 explicit affected versions
43 explicit affected versions
8 explicit affected versions
5 explicit affected versions
8 explicit affected versions
10 explicit affected versions
13 explicit affected versions
7 explicit affected versions
8 explicit affected versions
10 explicit affected versions
12 explicit affected versions
26 explicit affected versions
9 explicit affected versions
44 explicit affected versions
16 explicit affected versions
3 explicit affected versions
13 explicit affected versions
45 explicit affected versions
37 explicit affected versions
50 explicit affected versions
14 explicit affected versions
38 explicit affected versions
9 explicit affected versions
11 explicit affected versions
39 explicit affected versions
18 explicit affected versions
10 explicit affected versions
8 explicit affected versions
45 explicit affected versions
14 explicit affected versions
4 explicit affected versions
78 explicit affected versions
11 explicit affected versions
1 explicit affected versions
19 explicit affected versions
39 explicit affected versions
03 / CONNECTIONS
Connected vulnerabilities
04 / EVIDENCE
Source records
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
05 / REFERENCES
Further evidence
- https://git.kernel.org/linus/881a0263d502e1a93ebc13a78254e9ad19520232
- https://git.kernel.org/stable/c/0a47c3889fcd843c72aa57fa8c4d06f5801fced4
- https://git.kernel.org/stable/c/403182e0771b250cfde0fe7e1081d095ceaf8230
- https://git.kernel.org/stable/c/58f5d34f88e8f00910b692537f7b2efdb8c3705d
- https://git.kernel.org/stable/c/881a0263d502e1a93ebc13a78254e9ad19520232
- https://git.kernel.org/stable/c/88f974fe118cb4653f029929ecbca7cfe06132ae
- https://git.kernel.org/stable/c/c6783bfa31a59f34fe4feb1bdbf67791ef3fb0b7
- https://ubuntu.com/security/CVE-2026-43371
- https://ubuntu.com/security/notices/USN-8567-1
- https://ubuntu.com/security/notices/USN-8574-1
- https://ubuntu.com/security/notices/USN-8574-2
- https://ubuntu.com/security/notices/USN-8574-3
- https://ubuntu.com/security/notices/USN-8595-1
- https://ubuntu.com/security/notices/USN-8595-2
- https://ubuntu.com/security/notices/USN-8595-3
- https://ubuntu.com/security/notices/USN-8596-1
- https://ubuntu.com/security/notices/USN-8608-1
- https://www.cve.org/CVERecord?id=CVE-2026-43371