GHSA-R4V9-GF4R-42WW
Vulnerability from github – Published: 2026-08-15 06:32 – Updated: 2026-08-15 06:32In the Linux kernel, the following vulnerability has been resolved:
ieee802154: ca8210: fix pointer truncation in kfifo on 64-bit
ca8210_test_int_driver_write() and ca8210_test_int_user_read() exchange a kmalloc'd buffer pointer through a struct kfifo, but pass a literal '4' as the byte count to kfifo_in()/kfifo_out().
This is correct on 32-bit (pointer = 4 bytes), but on 64-bit only the low 4 bytes of the 8-byte pointer are written into the FIFO. The reader then reads back 4 bytes into an 8-byte local pointer variable, leaving the upper 4 bytes uninitialized stack data. The first dereference of the reconstructed pointer (fifo_buffer[1]) accesses an arbitrary kernel address and generally results in an oops.
Use sizeof(fifo_buffer) so the byte count matches pointer width on every architecture.
The driver has no architecture restriction in Kconfig, so any 64-bit build with CONFIG_IEEE802154_CA8210_DEBUGFS=y is exposed. Issue has been latent since the driver was added in 2017 because it is most commonly deployed on 32-bit MCUs.
Found via a custom Coccinelle semantic patch hunting for short-byte kfifo I/O on byte-mode kfifos used to shuttle pointers.
{
"affected": [],
"aliases": [
"CVE-2026-72047"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-08-15T06:21:13Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nieee802154: ca8210: fix pointer truncation in kfifo on 64-bit\n\nca8210_test_int_driver_write() and ca8210_test_int_user_read() exchange\na kmalloc\u0027d buffer pointer through a struct kfifo, but pass a literal\n\u00274\u0027 as the byte count to kfifo_in()/kfifo_out().\n\nThis is correct on 32-bit (pointer = 4 bytes), but on 64-bit only the\nlow 4 bytes of the 8-byte pointer are written into the FIFO. The reader\nthen reads back 4 bytes into an 8-byte local pointer variable, leaving\nthe upper 4 bytes uninitialized stack data. The first dereference of\nthe reconstructed pointer (fifo_buffer[1]) accesses an arbitrary kernel\naddress and generally results in an oops.\n\nUse sizeof(fifo_buffer) so the byte count matches pointer width on every\narchitecture.\n\nThe driver has no architecture restriction in Kconfig, so any 64-bit\nbuild with CONFIG_IEEE802154_CA8210_DEBUGFS=y is exposed. Issue has\nbeen latent since the driver was added in 2017 because it is most\ncommonly deployed on 32-bit MCUs.\n\nFound via a custom Coccinelle semantic patch hunting for short-byte\nkfifo I/O on byte-mode kfifos used to shuttle pointers.",
"id": "GHSA-r4v9-gf4r-42ww",
"modified": "2026-08-15T06:32:10Z",
"published": "2026-08-15T06:32:10Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-72047"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/093aacb0c56d5c693e3169a0224062e77c3fd0c0"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/1fe2643d0b24ca3cdd61a31a45c2d3233dc6cbfe"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/2059c28bd725beded01277cdf1f67be33e714323"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/2c1664ccfae653979b38788211240b5a1ee317ed"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/65dc342274a01616f5c17105f7360a3b4bfd7a3d"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/6d7f7bcf225b2d566176bf6229dbd1252940cb3c"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/87dab14a4f68895d6f4d798e6ee3556cd64e8c72"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/d8ce67fa6a5e6929f5414e933ff9665176c2bce6"
}
],
"schema_version": "1.4.0",
"severity": []
}
Sightings
| Author | Source | Type | Date | Other |
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Nomenclature
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