{"id":"CVE-2023-52928","summary":"bpf: Skip invalid kfunc call in backtrack_insn","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Skip invalid kfunc call in backtrack_insn\n\nThe verifier skips invalid kfunc call in check_kfunc_call(), which\nwould be captured in fixup_kfunc_call() if such insn is not eliminated\nby dead code elimination. However, this can lead to the following\nwarning in backtrack_insn(), also see [1]:\n\n  ------------[ cut here ]------------\n  verifier backtracking bug\n  WARNING: CPU: 6 PID: 8646 at kernel/bpf/verifier.c:2756 backtrack_insn\n  kernel/bpf/verifier.c:2756\n\t__mark_chain_precision kernel/bpf/verifier.c:3065\n\tmark_chain_precision kernel/bpf/verifier.c:3165\n\tadjust_reg_min_max_vals kernel/bpf/verifier.c:10715\n\tcheck_alu_op kernel/bpf/verifier.c:10928\n\tdo_check kernel/bpf/verifier.c:13821 [inline]\n\tdo_check_common kernel/bpf/verifier.c:16289\n  [...]\n\nSo make backtracking conservative with this by returning ENOTSUPP.\n\n  [1] https://lore.kernel.org/bpf/CACkBjsaXNceR8ZjkLG=dT3P=4A8SBsg0Z5h5PWLryF5=ghKq=g@mail.gmail.com/","modified":"2026-05-18T05:56:52.337032152Z","published":"2025-03-27T16:37:10.471Z","related":["SUSE-SU-2025:01620-1","SUSE-SU-2025:01640-1"],"database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/52xxx/CVE-2023-52928.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/6e2fac197de2c4c041bdd8982cffb104689113f1"},{"type":"WEB","url":"https://git.kernel.org/stable/c/74eec8266f37aff609db6a2f2b093e56a11c28c4"},{"type":"WEB","url":"https://git.kernel.org/stable/c/d3178e8a434b58678d99257c0387810a24042fb6"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/52xxx/CVE-2023-52928.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2023-52928"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"e6ac2450d6dee3121cd8bbf2907b78a68a8a353d"},{"fixed":"6e2fac197de2c4c041bdd8982cffb104689113f1"},{"fixed":"74eec8266f37aff609db6a2f2b093e56a11c28c4"},{"fixed":"d3178e8a434b58678d99257c0387810a24042fb6"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2023-52928.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"5.13.0"},{"fixed":"5.15.93"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.11"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2023-52928.json"}}],"schema_version":"1.7.5"}