{"cve":"CVE-2026-89482","nvd":{"published":"2026-09-11T20:19:29.730","modified":"2026-10-19T09:17:41.540","status":"Received","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnvme-tcp: do not accept C2HData based on blk_rq_payload_bytes() alone\n\nCommit 25e5cb780e62 (\"nvme-tcp: fix possible crash in write_zeroes\nprocessing\") established that blk_rq_payload_bytes() must not be read\nwithout first checking blk_rq_nr_phys_segments(), and recorded the\nresult in nvme_tcp_setup_cmd_pdu() as req->data_len. The receive side\nwas left as it was.\n\nThe two differ for REQ_OP_WRITE_ZEROES, which has no physical segments\nbut a non-zero blk_rq_bytes(), so setup leaves req->iter untouched\nwhile the receive gate lets a C2HData through and nvme_tcp_recv_data()\ncopies into whatever the previous command on that tag left there. The\ndriver-private area is zeroed only when the tag set is allocated.\n\nReproduced with a test target that leaves a residual iterator on a tag\nand then sends a C2HData for a WRITE_ZEROES command on the same tag:\n\nBUG: KASAN: wild-memory-access in _copy_to_iter+0x642/0x1330\nWrite of size 512 at addr ffe728c2175dfa81 by task kworker/0:1H/103\n\nCPU: 0 UID: 0 PID: 103 Comm: kworker/0:1H Not tainted 7.2.0-rc5-NVMETCP-gf5098b6bae76 #1 PREEMPT(lazy)\nHardware name: QEMU Ubuntu 24.04 PC v2 (i440FX + PIIX, arch_caps fix, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014\nWorkqueue: nvme_tcp_wq nvme_tcp_io_work\nCall Trace:\n <TASK>\n dump_stack_lvl+0x53/0x70\n kasan_report+0xce/0x100\n ? _copy_to_iter+0x642/0x1330\n kasan_check_range+0x105/0x1b0\n __asan_memcpy+0x3c/0x60\n _copy_to_iter+0x642/0x1330\n ? __pfx_sock_has_perm+0x10/0x10\n ? worker_thread+0x45b/0xd10\n ? __pfx__copy_to_iter+0x10/0x10\n ? _raw_spin_lock_bh+0x83/0xe0\n ? __pfx__raw_spin_lock_bh+0x10/0x10\n __skb_datagram_iter+0xf3/0x820\n ? __pfx_simple_copy_to_iter+0x10/0x10\n ? __asan_memcpy+0x3c/0x60\n ? skb_copy_bits+0x58d/0x830\n skb_copy_datagram_iter+0x37/0x120\n nvme_tcp_recv_skb+0xa07/0x4320\n ? __pfx_nvme_tcp_recv_skb+0x10/0x10\n __tcp_read_sock+0x1ab/0x810\n ? __pfx_nvme_tcp_recv_skb+0x10/0x10\n ? __pfx_lock_sock_nested+0x10/0x10\n ? __pfx___tcp_read_sock+0x10/0x10\n nvme_tcp_try_recv+0x152/0x1e0\n ? __pfx_nvme_tcp_try_recv+0x10/0x10\n ? __pfx_mutex_unlock+0x10/0x10\n nvme_tcp_io_work+0x1e4/0x6c0\n ? __schedule+0x181a/0x49f0\n ? __pfx_nvme_tcp_io_work+0x10/0x10\n process_one_work+0x633/0x1030\n\nKeep the blk_rq_payload_bytes() test and add req->data_len to it. The\nold test is what rejects a C2HData naming a tag that is no longer in\nflight, because blk_update_request() zeroes rq->__data_len on\ncompletion; req->data_len and req->curr_bio are driver-private and\nsurvive completion, so they cannot stand in for it. Setup initialises\nthe iterator only when both req->curr_bio and req->data_len are set, so\nthe gate now tests the same two.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","score":9.8},"cwes":[],"references":["https://git.kernel.org/stable/c/32ea8ce96b9bd797c59c351ce490ffd97adaa8c0","https://git.kernel.org/stable/c/3a4aa9e6ad3e35f8e24d5eaf38ee4d437075fb36","https://git.kernel.org/stable/c/641ad3a30ba560f0a9a610376c568d7b75d2a2aa","https://git.kernel.org/stable/c/6a01b58263108eaf9869bb6f82f07709240c6589","https://git.kernel.org/stable/c/7ed0b61bbc145988be292c4d3ec580aebd8d2bcd"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:53:43.293028046+00:00"},"epss":{"cve":"CVE-2026-89482","score":0.00714,"percentile":0.53394,"date":"2026-10-25"},"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."]}