ghsa-pf4v-7q2j-5rw9
Vulnerability from github
In the Linux kernel, the following vulnerability has been resolved:
media: rainshadow-cec: fix TOCTOU race condition in rain_interrupt()
In the interrupt handler rain_interrupt(), the buffer full check on rain->buf_len is performed before acquiring rain->buf_lock. This creates a Time-of-Check to Time-of-Use (TOCTOU) race condition, as rain->buf_len is concurrently accessed and modified in the work handler rain_irq_work_handler() under the same lock.
Multiple interrupt invocations can race, with each reading buf_len before it becomes full and then proceeding. This can lead to both interrupts attempting to write to the buffer, incrementing buf_len beyond its capacity (DATA_SIZE) and causing a buffer overflow.
Fix this bug by moving the spin_lock() to before the buffer full check. This ensures that the check and the subsequent buffer modification are performed atomically, preventing the race condition. An corresponding spin_unlock() is added to the overflow path to correctly release the lock.
This possible bug was found by an experimental static analysis tool developed by our team.
{
"affected": [],
"aliases": [
"CVE-2025-39713"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-09-05T18:15:48Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nmedia: rainshadow-cec: fix TOCTOU race condition in rain_interrupt()\n\nIn the interrupt handler rain_interrupt(), the buffer full check on\nrain-\u003ebuf_len is performed before acquiring rain-\u003ebuf_lock. This\ncreates a Time-of-Check to Time-of-Use (TOCTOU) race condition, as\nrain-\u003ebuf_len is concurrently accessed and modified in the work\nhandler rain_irq_work_handler() under the same lock.\n\nMultiple interrupt invocations can race, with each reading buf_len\nbefore it becomes full and then proceeding. This can lead to both\ninterrupts attempting to write to the buffer, incrementing buf_len\nbeyond its capacity (DATA_SIZE) and causing a buffer overflow.\n\nFix this bug by moving the spin_lock() to before the buffer full\ncheck. This ensures that the check and the subsequent buffer modification\nare performed atomically, preventing the race condition. An corresponding\nspin_unlock() is added to the overflow path to correctly release the\nlock.\n\nThis possible bug was found by an experimental static analysis tool\ndeveloped by our team.",
"id": "GHSA-pf4v-7q2j-5rw9",
"modified": "2025-09-05T18:31:27Z",
"published": "2025-09-05T18:31:27Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-39713"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/1c2769dc80255824542ea5a4ff1a07dcdeb1603f"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/2964dbe631fd21ad7873b1752b895548d3c12496"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/3c3e33b7edca7a2d6a96801f287f9faeb684d655"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/6aaef1a75985865d8c6c5b65fb54152060faba48"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/7af160aea26c7dc9e6734d19306128cce156ec40"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/ed905fe7cba03cf22ae0b84cf1b73cd1c070423a"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/fbc81e78d75bf28972bc22b1599559557b1a1b83"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/ff9dd3db6cd4c6b54a2ecbc58151bea4ec63bc59"
}
],
"schema_version": "1.4.0",
"severity": []
}
Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
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- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.