{"id":"AZL-101852","summary":"CVE-2026-90294 affecting package kernel 6.6.150.1-1","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nIB/isert: delay the final Login Response until the session is registered\n\nisert_put_login_tx() puts the final Login Response on the wire before\n__transport_register_session(), which iscsi_post_login_handler() reaches\nonly after iscsi_target_do_login() returns.  An initiator that issues a\nSCSI command as soon as it sees that response can have it executed against\nan se_session whose se_tpg is still NULL, and the ib-comp-wq worker oopses\non the NULL dereference.\n\n Oops: general protection fault, probably for non-canonical address 0xdffffc000000000f: 0000 [#1] SMP KASAN NOPTI\n KASAN: null-ptr-deref in range [0x0000000000000078-0x000000000000007f]\n CPU: 0 UID: 0 PID: 178 Comm: kworker/0:1H Not tainted 7.2.0-rc5-V2CTL-gf5098b6bae76 #10 PREEMPT(lazy)\n Hardware 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\n Workqueue: ib-comp-wq ib_cq_poll_work\n RIP: 0010:target_submit+0xbe/0x390\n Code: fa 48 c1 ea 03 80 3c 02 00 0f 85 89 02 00 00 48 b8 00 00 00 00 00 fc ff df 4d 8b 64 24 18 49 8d 7c 24 78 48 89 fa 48 c1 ea 03 \u003c80\u003e 3c 02 00 0f 85 5a 02 00 00 48 8d 7b 78 4d 8b 6c 24 78 48 b8 00\n RSP: 0018:ffff8881058cfa78 EFLAGS: 00010206\n RAX: dffffc0000000000 RBX: ffff88810c78c6f0 RCX: ffffffff964bb363\n RDX: 000000000000000f RSI: 00000000fffffe00 RDI: 0000000000000078\n RBP: 1ffff11020b19f52 R08: 0000000000000001 R09: ffffed1020b19f52\n R10: 0000000000000003 R11: ffff88810596c000 R12: 0000000000000000\n R13: ffff88810c61b000 R14: ffff88810c6a3400 R15: ffff88810c61b044\n FS:  0000000000000000(0000) GS:ffff8881822b2000(0000) knlGS:0000000000000000\n CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n CR2: 00007f1f1b83c000 CR3: 000000006fe72001 CR4: 0000000000770ef0\n PKRU: 55555554\n Call Trace:\n  \u003cTASK\u003e\n  ? __pfx__raw_spin_lock_bh+0x10/0x10\n  ? __pfx_target_submit+0x10/0x10\n  ? mutex_lock+0x81/0xe0\n  ? __pfx_mutex_lock+0x10/0x10\n  ? iscsit_execute_cmd+0x650/0x850\n  iscsit_sequence_cmd+0x186/0x3d0\n  iscsit_process_scsi_cmd+0x87/0x300\n  isert_recv_done+0x1002/0x2390\n  ? __pfx_isert_recv_done+0x10/0x10\n  ? rxe_poll_cq+0x253/0x3d0\n  ? finish_task_switch.isra.0+0x1dc/0xa70\n  __ib_process_cq+0xe1/0x390\n  ib_cq_poll_work+0x46/0x150\n  process_one_work+0x633/0x1030\n  ? assign_work+0x11d/0x370\n  worker_thread+0x45b/0xd10\n  ? __pfx_worker_thread+0x10/0x10\n  ? __pfx_worker_thread+0x10/0x10\n  kthread+0x2c6/0x3b0\n  ? recalc_sigpending+0x15c/0x1e0\n  ? __pfx_kthread+0x10/0x10\n  ret_from_fork+0x36e/0x5a0\n  ? __pfx_ret_from_fork+0x10/0x10\n  ? __switch_to+0x572/0xdd0\n  ? __pfx_kthread+0x10/0x10\n  ret_from_fork_asm+0x1a/0x30\n  \u003c/TASK\u003e\n Modules linked in:\n ---[ end trace 0000000000000000 ]---\n\nDelay the final Login Response instead.  isert_get_rx_pdu() runs from\niscsi_target_rx_thread() after conn-\u003erx_login_comp, completed by\niscsi_post_login_handler() after __transport_register_session(); iscsi-TCP\nand cxgbit already take PDUs from that thread, isert alone does not.  The\nbuffers are still posted first, so the initiator's first command does not\nmeet an empty receive queue and nothing depends on RNR flow control, and\nthe header and payload live in isert_conn, not in the struct iscsi_login\nthat iscsi_target_nego_release() frees first.\n\nOver rxe, 400 login cycles per run, the oops appeared in 10 of 20\nunpatched runs and in none of 20 runs with this patch.  An\ninitiator that never waits is handled by the next patch.\n\nNot tested: iWARP, discovery sessions over iSER, and real HCAs.","modified":"2026-09-18T14:16:28.512708235Z","published":"2026-09-17T17:17:26Z","upstream":["CVE-2026-90294"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-90294"}],"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-101852.json"}}],"schema_version":"1.9.0"}