{"id":"CVE-2024-56544","url":"https://www.cyber-defence.io/tools/cve/CVE-2024-56544","generatedAt":"2026-10-28T02:56:35.665Z","title":"In the Linux kernel, the following vulnerability has been resolved: udmabuf: change folios array from kmalloc to kvmalloc When PAGE_SIZE 4096, MAX_PAGE_ORDER 10, 64bit machine, page_alloc only support 4MB.","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nudmabuf: change folios array from kmalloc to kvmalloc\n\nWhen PAGE_SIZE 4096, MAX_PAGE_ORDER 10, 64bit machine,\npage_alloc only support 4MB.\nIf above this, trigger this warn and return NULL.\n\nudmabuf can change size limit, if change it to 3072(3GB), and then alloc\n3GB udmabuf, will fail create.\n\n[ 4080.876581] ------------[ cut here ]------------\n[ 4080.876843] WARNING: CPU: 3 PID: 2015 at mm/page_alloc.c:4556 __alloc_pages+0x2c8/0x350\n[ 4080.878839] RIP: 0010:__alloc_pages+0x2c8/0x350\n[ 4080.879470] Call Trace:\n[ 4080.879473]  <TASK>\n[ 4080.879473]  ? __alloc_pages+0x2c8/0x350\n[ 4080.879475]  ? __warn.cold+0x8e/0xe8\n[ 4080.880647]  ? __alloc_pages+0x2c8/0x350\n[ 4080.880909]  ? report_bug+0xff/0x140\n[ 4080.881175]  ? handle_bug+0x3c/0x80\n[ 4080.881556]  ? exc_invalid_op+0x17/0x70\n[ 4080.881559]  ? asm_exc_invalid_op+0x1a/0x20\n[ 4080.882077]  ? udmabuf_create+0x131/0x400\n\nBecause MAX_PAGE_ORDER, kmalloc can max alloc 4096 * (1 << 10), 4MB\nmemory, each array entry is pointer(8byte), so can save 524288 pages(2GB).\n\nFurther more, costly order(order 3) may not be guaranteed that it can be\napplied for, due to fragmentation.\n\nThis patch change udmabuf array use kvmalloc_array, this can fallback\nalloc into vmalloc, which can guarantee allocation for any size and does\nnot affect the performance of kmalloc allocations.","published":"2024-12-27T14:15:34.000Z","lastModified":"2026-10-21T13:17:52.000Z","status":"Modified","sourceIdentifier":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","cvss":{"version":"3.1","score":5.5,"severity":"MEDIUM","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"},"cwe":["CWE-476"],"affected":["linux/linux kernel"],"epss":{"score":0.00254,"percentile":0.16727,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and a low EPSS score (0.25%). Track it; it rarely justifies an emergency change on its own."},"changes":[],"references":[{"url":"https://git.kernel.org/stable/c/1c0844c6184e658064e14c4335885785ad3bf84b","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/2384a29db79bd2cfe0b7646ac0030cb355825e29","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/2acc6192aa8570661ed37868c02c03002b1dc290","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/85bb72397cb63649fe493c96e27e1d0e4ed2ff63","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2024-56544","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}