{"cve":"CVE-2023-54247","nvd":{"published":"2025-12-30T13:16:13.327","modified":"2026-06-17T06:47:05.280","status":"Deferred","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Silence a warning in btf_type_id_size()\n\nsyzbot reported a warning in [1] with the following stacktrace:\n  WARNING: CPU: 0 PID: 5005 at kernel/bpf/btf.c:1988 btf_type_id_size+0x2d9/0x9d0 kernel/bpf/btf.c:1988\n  ...\n  RIP: 0010:btf_type_id_size+0x2d9/0x9d0 kernel/bpf/btf.c:1988\n  ...\n  Call Trace:\n   <TASK>\n   map_check_btf kernel/bpf/syscall.c:1024 [inline]\n   map_create+0x1157/0x1860 kernel/bpf/syscall.c:1198\n   __sys_bpf+0x127f/0x5420 kernel/bpf/syscall.c:5040\n   __do_sys_bpf kernel/bpf/syscall.c:5162 [inline]\n   __se_sys_bpf kernel/bpf/syscall.c:5160 [inline]\n   __x64_sys_bpf+0x79/0xc0 kernel/bpf/syscall.c:5160\n   do_syscall_x64 arch/x86/entry/common.c:50 [inline]\n   do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80\n   entry_SYSCALL_64_after_hwframe+0x63/0xcd\n\nWith the following btf\n  [1] DECL_TAG 'a' type_id=4 component_idx=-1\n  [2] PTR '(anon)' type_id=0\n  [3] TYPE_TAG 'a' type_id=2\n  [4] VAR 'a' type_id=3, linkage=static\nand when the bpf_attr.btf_key_type_id = 1 (DECL_TAG),\nthe following WARN_ON_ONCE in btf_type_id_size() is triggered:\n  if (WARN_ON_ONCE(!btf_type_is_modifier(size_type) &&\n                   !btf_type_is_var(size_type)))\n          return NULL;\n\nNote that 'return NULL' is the correct behavior as we don't want\na DECL_TAG type to be used as a btf_{key,value}_type_id even\nfor the case like 'DECL_TAG -> STRUCT'. So there\nis no correctness issue here, we just want to silence warning.\n\nTo silence the warning, I added DECL_TAG as one of kinds in\nbtf_type_nosize() which will cause btf_type_id_size() returning\nNULL earlier without the warning.\n\n  [1] https://lore.kernel.org/bpf/000000000000e0df8d05fc75ba86@google.com/","cvss_v4":null,"cvss_v3":null,"cwes":[],"references":["https://git.kernel.org/stable/c/61f4bd46a03a81865aca3bcbad2f7b7032fb3160","https://git.kernel.org/stable/c/7c4f5ab63e7962812505cbd38cc765168a223acb","https://git.kernel.org/stable/c/e6c2f594ed961273479505b42040782820190305"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:18:08.089039631+00:00"},"epss":{"cve":"CVE-2023-54247","score":0.00198,"percentile":0.09597,"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."]}