{"id":"CVE-2023-52767","summary":"tls: fix NULL deref on tls_sw_splice_eof() with empty record","details":"In the Linux kernel, the following vulnerability has been resolved:\n\ntls: fix NULL deref on tls_sw_splice_eof() with empty record\n\nsyzkaller discovered that if tls_sw_splice_eof() is executed as part of\nsendfile() when the plaintext/ciphertext sk_msg are empty, the send path\ngets confused because the empty ciphertext buffer does not have enough\nspace for the encryption overhead. This causes tls_push_record() to go on\nthe `split = true` path (which is only supposed to be used when interacting\nwith an attached BPF program), and then get further confused and hit the\ntls_merge_open_record() path, which then assumes that there must be at\nleast one populated buffer element, leading to a NULL deref.\n\nIt is possible to have empty plaintext/ciphertext buffers if we previously\nbailed from tls_sw_sendmsg_locked() via the tls_trim_both_msgs() path.\ntls_sw_push_pending_record() already handles this case correctly; let's do\nthe same check in tls_sw_splice_eof().","modified":"2026-04-02T09:43:19.045562Z","published":"2024-05-21T15:30:50.993Z","related":["SUSE-SU-2024:2571-1","SUSE-SU-2024:2896-1","SUSE-SU-2024:2973-1","SUSE-SU-2025:20008-1","SUSE-SU-2025:20028-1"],"database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/52xxx/CVE-2023-52767.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/2214e2bb5489145aba944874d0ee1652a0a63dc8"},{"type":"WEB","url":"https://git.kernel.org/stable/c/53f2cb491b500897a619ff6abd72f565933760f0"},{"type":"WEB","url":"https://git.kernel.org/stable/c/944900fe2736c07288efe2d9394db4d3ca23f2c9"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/52xxx/CVE-2023-52767.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2023-52767"},{"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":"5ad627faed136089e27bcd15e0c33760e575c8c3"},{"fixed":"944900fe2736c07288efe2d9394db4d3ca23f2c9"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"df720d288dbb1793e82b6ccbfc670ec871e9def4"},{"fixed":"2214e2bb5489145aba944874d0ee1652a0a63dc8"},{"fixed":"53f2cb491b500897a619ff6abd72f565933760f0"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2023-52767.json"}}],"schema_version":"1.7.5"}