ghsa-hx2r-xg86-xj35
Vulnerability from github
In the Linux kernel, the following vulnerability has been resolved:
spi: Fix deadlock when adding SPI controllers on SPI buses
Currently we have a global spi_add_lock which we take when adding new devices so that we can check that we're not trying to reuse a chip select that's already controlled. This means that if the SPI device is itself a SPI controller and triggers the instantiation of further SPI devices we trigger a deadlock as we try to register and instantiate those devices while in the process of doing so for the parent controller and hence already holding the global spi_add_lock. Since we only care about concurrency within a single SPI bus move the lock to be per controller, avoiding the deadlock.
This can be easily triggered in the case of spi-mux.
{
"affected": [],
"aliases": [
"CVE-2021-47469"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-05-22T07:15:11Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nspi: Fix deadlock when adding SPI controllers on SPI buses\n\nCurrently we have a global spi_add_lock which we take when adding new\ndevices so that we can check that we\u0027re not trying to reuse a chip\nselect that\u0027s already controlled. This means that if the SPI device is\nitself a SPI controller and triggers the instantiation of further SPI\ndevices we trigger a deadlock as we try to register and instantiate\nthose devices while in the process of doing so for the parent controller\nand hence already holding the global spi_add_lock. Since we only care\nabout concurrency within a single SPI bus move the lock to be per\ncontroller, avoiding the deadlock.\n\nThis can be easily triggered in the case of spi-mux.",
"id": "GHSA-hx2r-xg86-xj35",
"modified": "2024-05-22T09:31:45Z",
"published": "2024-05-22T09:31:45Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2021-47469"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/6098475d4cb48d821bdf453c61118c56e26294f0"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/722ef19a161ce3fffb3d1b01ce2301c306639bdd"
}
],
"schema_version": "1.4.0",
"severity": []
}