ghsa-9pg7-c56m-xqjx
Vulnerability from github
In the Linux kernel, the following vulnerability has been resolved:
wifi: brcmfmac: Fix oops due to NULL pointer dereference in brcmf_sdiod_sglist_rw()
This patch fixes a NULL pointer dereference bug in brcmfmac that occurs when a high 'sd_sgentry_align' value applies (e.g. 512) and a lot of queued SKBs are sent from the pkt queue.
The problem is the number of entries in the pre-allocated sgtable, it is nents = max(rxglom_size, txglom_size) + max(rxglom_size, txglom_size) >> 4 + 1. Given the default [rt]xglom_size=32 it's actually 35 which is too small. Worst case, the pkt queue can end up with 64 SKBs. This occurs when a new SKB is added for each original SKB if tailroom isn't enough to hold tail_pad. At least one sg entry is needed for each SKB. So, eventually the "skb_queue_walk loop" in brcmf_sdiod_sglist_rw may run out of sg entries. This makes sg_next return NULL and this causes the oops.
The patch sets nents to max(rxglom_size, txglom_size) * 2 to be able handle the worst-case. Btw. this requires only 64-35=29 * 16 (or 20 if CONFIG_NEED_SG_DMA_LENGTH) = 464 additional bytes of memory.
{
"affected": [],
"aliases": [
"CVE-2024-56593"
],
"database_specific": {
"cwe_ids": [
"CWE-476"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-12-27T15:15:18Z",
"severity": "MODERATE"
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nwifi: brcmfmac: Fix oops due to NULL pointer dereference in brcmf_sdiod_sglist_rw()\n\nThis patch fixes a NULL pointer dereference bug in brcmfmac that occurs\nwhen a high \u0027sd_sgentry_align\u0027 value applies (e.g. 512) and a lot of queued SKBs\nare sent from the pkt queue.\n\nThe problem is the number of entries in the pre-allocated sgtable, it is\nnents = max(rxglom_size, txglom_size) + max(rxglom_size, txglom_size) \u003e\u003e 4 + 1.\nGiven the default [rt]xglom_size=32 it\u0027s actually 35 which is too small.\nWorst case, the pkt queue can end up with 64 SKBs. This occurs when a new SKB\nis added for each original SKB if tailroom isn\u0027t enough to hold tail_pad.\nAt least one sg entry is needed for each SKB. So, eventually the \"skb_queue_walk loop\"\nin brcmf_sdiod_sglist_rw may run out of sg entries. This makes sg_next return\nNULL and this causes the oops.\n\nThe patch sets nents to max(rxglom_size, txglom_size) * 2 to be able handle\nthe worst-case.\nBtw. this requires only 64-35=29 * 16 (or 20 if CONFIG_NEED_SG_DMA_LENGTH) = 464\nadditional bytes of memory.",
"id": "GHSA-9pg7-c56m-xqjx",
"modified": "2025-01-08T18:30:47Z",
"published": "2024-12-27T15:31:54Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-56593"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/07c020c6d14d29e5a3ea4e4576b8ecf956a80834"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/342f87d263462c2670b77ea9a32074cab2ac6fa1"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/34941321b516bd7c6103bd01287d71a1804d19d3"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/67a25ea28f8ec1da8894f2f115d01d3becf67dc7"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/7522d7d745d13fbeff3350fe6aa56c8dae263571"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/857282b819cbaa0675aaab1e7542e2c0579f52d7"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/dfb3f9d3f602602de208da7bdcc0f6d5ee74af68"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
"type": "CVSS_V3"
}
]
}
Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- 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.