GHSA-R5PJ-8MRW-4GQJ
Vulnerability from github – Published: 2024-12-27 15:31 – Updated: 2025-11-03 21:31In the Linux kernel, the following vulnerability has been resolved:
nfsd: make sure exp active before svc_export_show
The function e_show was called with protection from RCU. This only
ensures that exp will not be freed. Therefore, the reference count for
exp can drop to zero, which will trigger a refcount use-after-free
warning when exp_get is called. To resolve this issue, use
cache_get_rcu to ensure that exp remains active.
------------[ cut here ]------------ refcount_t: addition on 0; use-after-free. WARNING: CPU: 3 PID: 819 at lib/refcount.c:25 refcount_warn_saturate+0xb1/0x120 CPU: 3 UID: 0 PID: 819 Comm: cat Not tainted 6.12.0-rc3+ #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.1-2.fc37 04/01/2014 RIP: 0010:refcount_warn_saturate+0xb1/0x120 ... Call Trace: e_show+0x20b/0x230 [nfsd] seq_read_iter+0x589/0x770 seq_read+0x1e5/0x270 vfs_read+0x125/0x530 ksys_read+0xc1/0x160 do_syscall_64+0x5f/0x170 entry_SYSCALL_64_after_hwframe+0x76/0x7e
{
"affected": [],
"aliases": [
"CVE-2024-56558"
],
"database_specific": {
"cwe_ids": [
"CWE-416"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-12-27T15:15:14Z",
"severity": "HIGH"
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnfsd: make sure exp active before svc_export_show\n\nThe function `e_show` was called with protection from RCU. This only\nensures that `exp` will not be freed. Therefore, the reference count for\n`exp` can drop to zero, which will trigger a refcount use-after-free\nwarning when `exp_get` is called. To resolve this issue, use\n`cache_get_rcu` to ensure that `exp` remains active.\n\n------------[ cut here ]------------\nrefcount_t: addition on 0; use-after-free.\nWARNING: CPU: 3 PID: 819 at lib/refcount.c:25\nrefcount_warn_saturate+0xb1/0x120\nCPU: 3 UID: 0 PID: 819 Comm: cat Not tainted 6.12.0-rc3+ #1\nHardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS\n1.16.1-2.fc37 04/01/2014\nRIP: 0010:refcount_warn_saturate+0xb1/0x120\n...\nCall Trace:\n \u003cTASK\u003e\n e_show+0x20b/0x230 [nfsd]\n seq_read_iter+0x589/0x770\n seq_read+0x1e5/0x270\n vfs_read+0x125/0x530\n ksys_read+0xc1/0x160\n do_syscall_64+0x5f/0x170\n entry_SYSCALL_64_after_hwframe+0x76/0x7e",
"id": "GHSA-r5pj-8mrw-4gqj",
"modified": "2025-11-03T21:31:50Z",
"published": "2024-12-27T15:31:53Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-56558"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/1cecfdbc6bfc89c516d286884c7f29267b95de2b"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/6cefcadd34e3c71c81ea64b899a0daa86314a51a"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/7365d1f8de63cffdbbaa2287ce0205438e1a922f"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/7d8f7816bebcd2e7400bb4d786eccb8f33c9f9ec"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/7fd29d284b55c2274f7a748e6c5f25b4758b8da5"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/be8f982c369c965faffa198b46060f8853e0f1f0"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/e2fa0d0e327279a8defb87b263cd0bf288fd9261"
},
{
"type": "WEB",
"url": "https://lists.debian.org/debian-lts-announce/2025/03/msg00001.html"
},
{
"type": "WEB",
"url": "https://lists.debian.org/debian-lts-announce/2025/03/msg00002.html"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
Sightings
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|---|
Nomenclature
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