{"id":"CVE-2026-89480","summary":"nvme-tcp: reject a read that transferred too few bytes","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnvme-tcp: reject a read that transferred too few bytes\n\nnvme_tcp_recv_data() completes a request once the current C2HData PDU\nhas been consumed. Nothing compares the total bytes received against\nthe length the command asked for: struct nvme_tcp_request has no\nreceive-side counter, queue-\u003edata_remaining is per queue, and\nblk_mq_end_request() completes for blk_rq_bytes(rq) unconditionally\nwith no residual concept anywhere above.\n\nA controller can therefore answer a 4096-byte read with 512 bytes and\nhave it reported as a complete read; user space then gets 4096 bytes of\nwhich 3584 are whatever was already in the page. I reproduced that with\na test target.\n\nCount the bytes received and refuse to complete a successful read whose\ncount does not match, at the two NVME_TCP_F_DATA_SUCCESS paths and in\nnvme_tcp_process_nvme_cqe(). The success test shifts req-\u003estatus right\nby one, because the driver keeps the wire value there and shifts it on\ncompletion, so the check must see what the completion path will see.\nOnly REQ_OP_READ is checked, because there the length comes from the\nsectors the request covers; a passthrough command is built by its\nsubmitter, which picks both command and buffer, so the kernel has\nnothing to compare against.","modified":"2026-09-13T03:47:18.192326728Z","published":"2026-09-11T19:43:35.930Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89480.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/7fa3f73f6c8ddc5f0425b50fb2a626a782ef7d12"},{"type":"WEB","url":"https://git.kernel.org/stable/c/832a685efeb5d925ee7d30011d2dbe45f81447a3"},{"type":"WEB","url":"https://git.kernel.org/stable/c/8a02ad98798fd01f51f648c1fdd8f3c9d07195d3"},{"type":"WEB","url":"https://git.kernel.org/stable/c/99066cf9bba175f610ceb61a35f6fc9fbc33ff65"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89480.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89480"},{"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":"3f2304f8c6d6ed97849057bd16fee99e434ca796"},{"fixed":"99066cf9bba175f610ceb61a35f6fc9fbc33ff65"},{"fixed":"8a02ad98798fd01f51f648c1fdd8f3c9d07195d3"},{"fixed":"832a685efeb5d925ee7d30011d2dbe45f81447a3"},{"fixed":"7fa3f73f6c8ddc5f0425b50fb2a626a782ef7d12"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-89480.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"5.0.0"},{"fixed":"6.12.109"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.50"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.2.4"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-89480.json"}}],"schema_version":"1.9.0"}