ghsa-3792-937m-5pm4
Vulnerability from github
In the Linux kernel, the following vulnerability has been resolved:
crypto: zstd - fix double-free in per-CPU stream cleanup
The crypto/zstd module has a double-free bug that occurs when multiple tfms are allocated and freed.
The issue happens because zstd_streams (per-CPU contexts) are freed in zstd_exit() during every tfm destruction, rather than being managed at the module level. When multiple tfms exist, each tfm exit attempts to free the same shared per-CPU streams, resulting in a double-free.
This leads to a stack trace similar to:
BUG: Bad page state in process kworker/u16:1 pfn:106fd93 page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x106fd93 flags: 0x17ffffc0000000(node=0|zone=2|lastcpupid=0x1fffff) page_type: 0xffffffff() raw: 0017ffffc0000000 dead000000000100 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: nonzero entire_mapcount Modules linked in: ... CPU: 3 UID: 0 PID: 2506 Comm: kworker/u16:1 Kdump: loaded Tainted: G B Hardware name: ... Workqueue: btrfs-delalloc btrfs_work_helper Call Trace: dump_stack_lvl+0x5d/0x80 bad_page+0x71/0xd0 free_unref_page_prepare+0x24e/0x490 free_unref_page+0x60/0x170 crypto_acomp_free_streams+0x5d/0xc0 crypto_acomp_exit_tfm+0x23/0x50 crypto_destroy_tfm+0x60/0xc0 ...
Change the lifecycle management of zstd_streams to free the streams only once during module cleanup.
{
"affected": [],
"aliases": [
"CVE-2025-68262"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-12-16T15:15:55Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\ncrypto: zstd - fix double-free in per-CPU stream cleanup\n\nThe crypto/zstd module has a double-free bug that occurs when multiple\ntfms are allocated and freed.\n\nThe issue happens because zstd_streams (per-CPU contexts) are freed in\nzstd_exit() during every tfm destruction, rather than being managed at\nthe module level. When multiple tfms exist, each tfm exit attempts to\nfree the same shared per-CPU streams, resulting in a double-free.\n\nThis leads to a stack trace similar to:\n\n BUG: Bad page state in process kworker/u16:1 pfn:106fd93\n page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x106fd93\n flags: 0x17ffffc0000000(node=0|zone=2|lastcpupid=0x1fffff)\n page_type: 0xffffffff()\n raw: 0017ffffc0000000 dead000000000100 dead000000000122 0000000000000000\n raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000\n page dumped because: nonzero entire_mapcount\n Modules linked in: ...\n CPU: 3 UID: 0 PID: 2506 Comm: kworker/u16:1 Kdump: loaded Tainted: G B\n Hardware name: ...\n Workqueue: btrfs-delalloc btrfs_work_helper\n Call Trace:\n \u003cTASK\u003e\n dump_stack_lvl+0x5d/0x80\n bad_page+0x71/0xd0\n free_unref_page_prepare+0x24e/0x490\n free_unref_page+0x60/0x170\n crypto_acomp_free_streams+0x5d/0xc0\n crypto_acomp_exit_tfm+0x23/0x50\n crypto_destroy_tfm+0x60/0xc0\n ...\n\nChange the lifecycle management of zstd_streams to free the streams only\nonce during module cleanup.",
"id": "GHSA-3792-937m-5pm4",
"modified": "2025-12-16T15:30:47Z",
"published": "2025-12-16T15:30:47Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-68262"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/48bc9da3c97c15f1ea24934bcb3b736acd30163d"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/dc0f4509b0ed5d82bef78e058db0ac4df04d0695"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/e983feaa79de1e46c9087fb9f02fedb0e5397ce6"
}
],
"schema_version": "1.4.0",
"severity": []
}
Sightings
| Author | Source | Type | Date |
|---|
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