{"cve":"CVE-2024-56593","nvd":{"published":"2024-12-27T15:15:18.613","modified":"2026-06-17T08:12:29.780","status":"Modified","description":"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 'sd_sgentry_align' 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) >> 4 + 1.\nGiven the default [rt]xglom_size=32 it's 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't 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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":["CWE-476"],"references":["https://git.kernel.org/stable/c/07c020c6d14d29e5a3ea4e4576b8ecf956a80834","https://git.kernel.org/stable/c/342f87d263462c2670b77ea9a32074cab2ac6fa1","https://git.kernel.org/stable/c/34941321b516bd7c6103bd01287d71a1804d19d3","https://git.kernel.org/stable/c/67a25ea28f8ec1da8894f2f115d01d3becf67dc7","https://git.kernel.org/stable/c/7522d7d745d13fbeff3350fe6aa56c8dae263571"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T21:57:56.913276502+00:00"},"epss":{"cve":"CVE-2024-56593","score":0.0024,"percentile":0.15145,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}