ghsa-37c3-qm4g-jf9g
Vulnerability from github
In the Linux kernel, the following vulnerability has been resolved:
bpf, sockmap: Prevent lock inversion deadlock in map delete elem
syzkaller started using corpuses where a BPF tracing program deletes elements from a sockmap/sockhash map. Because BPF tracing programs can be invoked from any interrupt context, locks taken during a map_delete_elem operation must be hardirq-safe. Otherwise a deadlock due to lock inversion is possible, as reported by lockdep:
CPU0 CPU1
---- ----
lock(&htab->buckets[i].lock);
local_irq_disable();
lock(&host->lock);
lock(&htab->buckets[i].lock);
Locks in sockmap are hardirq-unsafe by design. We expects elements to be deleted from sockmap/sockhash only in task (normal) context with interrupts enabled, or in softirq context.
Detect when map_delete_elem operation is invoked from a context which is not hardirq-unsafe, that is interrupts are disabled, and bail out with an error.
Note that map updates are not affected by this issue. BPF verifier does not allow updating sockmap/sockhash from a BPF tracing program today.
{
"affected": [],
"aliases": [
"CVE-2024-35895"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-05-19T09:15:10Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf, sockmap: Prevent lock inversion deadlock in map delete elem\n\nsyzkaller started using corpuses where a BPF tracing program deletes\nelements from a sockmap/sockhash map. Because BPF tracing programs can be\ninvoked from any interrupt context, locks taken during a map_delete_elem\noperation must be hardirq-safe. Otherwise a deadlock due to lock inversion\nis possible, as reported by lockdep:\n\n CPU0 CPU1\n ---- ----\n lock(\u0026htab-\u003ebuckets[i].lock);\n local_irq_disable();\n lock(\u0026host-\u003elock);\n lock(\u0026htab-\u003ebuckets[i].lock);\n \u003cInterrupt\u003e\n lock(\u0026host-\u003elock);\n\nLocks in sockmap are hardirq-unsafe by design. We expects elements to be\ndeleted from sockmap/sockhash only in task (normal) context with interrupts\nenabled, or in softirq context.\n\nDetect when map_delete_elem operation is invoked from a context which is\n_not_ hardirq-unsafe, that is interrupts are disabled, and bail out with an\nerror.\n\nNote that map updates are not affected by this issue. BPF verifier does not\nallow updating sockmap/sockhash from a BPF tracing program today.",
"id": "GHSA-37c3-qm4g-jf9g",
"modified": "2024-08-29T18:31:32Z",
"published": "2024-05-19T09:34:47Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-35895"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/668b3074aa14829e2ac2759799537a93b60fef86"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/6af057ccdd8e7619960aca1f0428339f213b31cd"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/913c30f827e17d8cda1da6eeb990f350d36cb69b"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/a44770fed86515eedb5a7c00b787f847ebb134a5"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/d1e73fb19a4c872d7a399ad3c66e8ca30e0875ec"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/dd54b48db0c822ae7b520bc80751f0a0a173ef75"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/f7990498b05ac41f7d6a190dc0418ef1d21bf058"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/ff91059932401894e6c86341915615c5eb0eca48"
},
{
"type": "WEB",
"url": "https://lists.debian.org/debian-lts-announce/2024/06/msg00017.html"
}
],
"schema_version": "1.4.0",
"severity": []
}
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.