{"id":"AZL-101208","summary":"CVE-2026-89973 affecting package kernel 6.6.150.1-1","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnvme-tcp: check the data direction of a C2HData PDU\n\nnvme_tcp_handle_c2h_data() finds the request by command id and checks\nthat it has a payload, but it does not check that the command asked for\ndata to be read.  A controller that answers a write command with C2HData\ntherefore reaches nvme_tcp_recv_data(), where _copy_to_iter() hits\nWARN_ON_ONCE(i-\u003edata_source) and returns 0.  The receive path turns that\ninto -EFAULT and resets the controller.\n\nNo data is copied, so this is not memory corruption.  What a controller\ngets is a kernel warning it can raise at will, which is fatal on a host\nbooted with panic_on_warn.\n\nThe send path already knows the direction - it consults rq_data_dir()\nwhen it builds a command - and nvme_tcp_handle_r2t() checks the length\nand the offset of the request it names.  The C2HData path does not check\nthe direction at all.\n\nReject a C2HData PDU whose command is not a read.  Rejecting it fails\nthe command and resets the controller, as the neighbouring check in this\nfunction does; what goes away is the warning.\n\n  [    6.885580] ------------[ cut here ]------------\n  [    6.886457] WARNING: lib/iov_iter.c:193 at _copy_to_iter+0x289/0x1330, CPU#0: kworker/0:1H/71\n  [    6.888137] CPU: 0 UID: 0 PID: 71 Comm: kworker/0:1H Not tainted 7.2.0-rc5-NVMETCP-gf5098b6bae76 #1 PREEMPT(lazy)\n  [    6.891165] Workqueue: nvme_tcp_wq nvme_tcp_io_work\n  [    6.891875] RIP: 0010:_copy_to_iter+0x289/0x1330\n  [    6.903739] Call Trace:\n  [    6.904085]  \u003cTASK\u003e\n  [    6.909254]  __skb_datagram_iter+0x433/0x820\n  [    6.911026]  skb_copy_datagram_iter+0x37/0x120\n  [    6.911622]  nvme_tcp_recv_skb+0xa07/0x4320\n  [    6.913378]  __tcp_read_sock+0x1ab/0x810\n  [    6.915788]  nvme_tcp_try_recv+0x152/0x1e0\n  [    6.918222]  nvme_tcp_io_work+0x1e4/0x6c0\n  [    6.926906]  \u003c/TASK\u003e\n  [    6.927226] ---[ end trace 0000000000000000 ]---\n  [    6.927878] nvme nvme0: queue 1 failed to copy request 0x71 data\n  [    6.928709] nvme nvme0: receive failed:  -14","modified":"2026-09-17T14:15:47.816938873Z","published":"2026-09-16T11:17:08Z","upstream":["CVE-2026-89973"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89973"}],"affected":[{"package":{"name":"kernel","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/kernel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"6.6.150.1-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-101208.json"}}],"schema_version":"1.9.0"}