{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/smb/smbdirect/accept.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "959813a3752b459ed77b0b3eaf30b9f4c6204260",
              "status": "affected",
              "version": "eb3ed1e9048cf7b2a38112f48e0f1b772bb7860d",
              "versionType": "git"
            },
            {
              "lessThan": "383a9480f5f40bc46454cce27ccfad532cedad9c",
              "status": "affected",
              "version": "eb3ed1e9048cf7b2a38112f48e0f1b772bb7860d",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/smb/smbdirect/accept.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "7.1"
            },
            {
              "lessThan": "7.1",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.2.*",
              "status": "unaffected",
              "version": "7.2.6",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.3-rc1",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2.6",
                  "versionStartIncluding": "7.1",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.3-rc1",
                  "versionStartIncluding": "7.1",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsmb: smbdirect: destroy QP before mem pools on accept failure\n\nOn the rdma_accept_failed error path of\nsmbdirect_accept_connect_request(), the receive io posted just above is\nowned by the QP (recv_io is set to NULL after a successful post).  The\nerror path fell through to smbdirect_connection_destroy_mem_pools()\nbefore smbdirect_connection_destroy_qp(), so the mem pools and the\nrecv_io slab cache were destroyed while that recv_io was still\noutstanding on the QP.\n\nThe drain in smbdirect_connection_destroy_qp() (ib_drain_qp()) is what\nruns the recv completion that returns the recv_io to the free list, so\ndestroying the pools first leaves the object outstanding at\nkmem_cache_destroy() time (\"Slab cache still has objects\") and later\nfrees it into an already-destroyed mempool (mempool_free_bulk\nNULL-pointer dereference).\n\nGive rdma_accept_failed its own teardown that drains the QP first, then\ndestroys the mem pools, and returns.  The remaining labels\n(post_recv_io_failed onward) run before the recv_io was ever posted, so\nthey keep the mem-pools-then-qp order.\n\nThe outstanding recv_io at kmem_cache_destroy() time:\n\n[ 3487.344647] =============================================================================\n[ 3487.349942] BUG smbdirect_recv_io_cache_ffff88811ba99000 (Not tainted): Objects remaining on __kmem_cache_shutdown()\n[ 3487.356078] -----------------------------------------------------------------------------\n[ 3487.356078]\n[ 3487.356738] Object 0xffff8881511c3440 @offset=13376\n[ 3487.358464] Allocated in mempool_alloc_noprof+0x18c/0x290 age=1194 cpu=6 pid=22254\n[ 3487.361197]  mempool_alloc_noprof+0x18c/0x290\n[ 3487.361542]  smbdirect_connection_create_mem_pools+0x405/0x780\n[ 3487.361972]  smbdirect_accept_connect_request+0x5a8/0x1b80\n[ 3487.362359]  smbdirect_listen_rdma_event_handler+0x1579/0x1b90\n[ 3487.362779]  cma_cm_event_handler+0x9c/0x230\n[ 3487.363096]  cma_ib_req_handler+0x2682/0x45d0\n[ 3487.363414]  cm_process_work+0x56/0x3d0\n[ 3487.363676]  cm_work_handler+0x8a0e/0xd000\n[ 3487.367496]  process_scheduled_works+0xa07/0x13a0\n[ 3487.367859]  worker_thread+0x7c9/0xc80\n[ 3487.368148]  kthread+0x341/0x430\n[ 3487.368407]  ret_from_fork+0x3a8/0x7a0\n[ 3487.368704]  ret_from_fork_asm+0x1a/0x30\n[ 3487.370307] Slab 0xffffea0005447000 objects=19 used=1 fp=0xffff8881511c0040 flags=0x100000000000240(workingset|head|node=0|zone=2)\n[ 3487.372840] ------------[ cut here ]------------\n[ 3487.373195] WARNING: mm/slub.c:1244 at __slab_err+0x1a/0x30, CPU#6: kworker/6:84/22254\n[ 3487.373759] Modules linked in:\n[ 3487.373993] CPU: 6 UID: 0 PID: 22254 Comm: kworker/6:84 Tainted: G    B               7.1.0-next-20260623+ #88 PREEMPT(lazy)\n[ 3487.374778] Tainted: [B]=BAD_PAGE\n[ 3487.377830] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.17.0-debian-1.17.0-1 04/01/2014\n[ 3487.378515] Workqueue: ib_cm cm_work_handler\n[ 3487.378820] RIP: 0010:__slab_err+0x1a/0x30\n[ 3487.379129] Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 44 00 00 e8 36 00 00 00 bf 05 00 00 00 be 01 00 00 00 e8 f7 75 45 00 90 \u003c0f\u003e 0b 90 c3 cc cc cc cc cc 66 66 66 66 2e 0f 1f 84 00 00 00 00 00\n[ 3487.383255] RSP: 0018:ffff888220fc7050 EFLAGS: 00010093\n[ 3487.383643] RAX: ffffffff8168e60a RBX: ffff88810955e640 RCX: ffff88821c381d80\n[ 3487.384158] RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff870fa080\n[ 3487.384662] RBP: ffff888220fc7068 R08: ffffffff870fa087 R09: 1ffffffff0e1f410\n[ 3487.385192] R10: dffffc0000000000 R11: fffffbfff0e1f411 R12: ffffea0005447210\n[ 3487.385674] R13: ffffea0005447000 R14: ffff888220fc7068 R15: ffff88812a8ab300\n[ 3487.388932] FS:  0000000000000000(0000) GS:ffff888427e76000(0000) knlGS:0000000000000000\n[ 3487.389529] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n[ 3487.389934] CR2: 00007ffcf2d84fd8 CR3: 0000000111d64006 CR4: 0000000000f72ef0\n[ 3487.390440] PKRU: 55555554\n[ 3487.390641] Call Trace:\n[ 3487.390826]  \u003cTASK\u003e\n[ 3\n---truncated---"
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7.5,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:N - A remote RDMA peer sends an IB CM REQ (RDMA_CM_EVENT_CONNECT_REQUEST) that cma_ib_req_handler delivers to smbdirect_listen_rdma_event_handler; ksmbd_rdma_init() listens for that on RoCEv2/IB port 445 and iWARP port 5445, which are IP-routable SMB Direct transports.\nAC:L - smbdirect_accept_connect_request() takes rdma_accept_failed after smbdirect_connection_post_recv_io() has already posted the recv_io; the attacker makes rdma_accept() fail with a CONNECT_REQUEST whose CM REQ path/QP fields cause cma_modify_qp_rtr()/ib_send_cm_rep() to fail, so the error path is attacker-driven rather than a victim-side race.\nPR:N - The bug runs in smbdirect_accept_connect_request() from the listen CONNECT_REQUEST handler, before smbdirect_accept_negotiate_recv_done() processes the SMB Direct negotiate request and before ksmbd_conn_handler_loop() runs SMB2 SESSION_SETUP, so no credentials are checked.\nUI:N - Once ksmbd_rdma_init() has called smbdirect_socket_listen(), the attacker triggers the buggy teardown solely by sending the RDMA CM CONNECT_REQUEST that fails rdma_accept(); no victim mount or other interaction is required.\nS:U - The oops is in the host kernel on smbdirect_connection_destroy_mem_pools()/mempool_free_bulk() during ksmbd SMB Direct accept teardown and does not cross a VM, IOMMU, or other security authority.\nC:N - kmem_cache_destroy() of the per-connection smbdirect_recv_io_cache returns without freeing the still-posted recv_io, and the later mempool_free(recv_io, NULL) NULL-dereferences sc-\u003erecv_io.mem.pool in mempool_free_bulk(); that path does not return kernel memory to the RDMA peer.\nI:N - The outstanding recv_io is not actually released by the failed kmem_cache_destroy(), and mempool_free_bulk() oopses on the NULL pool pointer before any write through a dangling object, so there is no integrity or code-execution primitive.\nA:H - After ib_drain_qp() in smbdirect_connection_destroy_qp() returns the posted recv_io onto the free list, smbdirect_socket_release() calls smbdirect_connection_destroy_mem_pools() again, which mempool_free()s it with sc-\u003erecv_io.mem.pool already NULL and oopses in mempool_free_bulk()."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-09-18T17:53:32.077Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/959813a3752b459ed77b0b3eaf30b9f4c6204260"
        },
        {
          "url": "https://git.kernel.org/stable/c/383a9480f5f40bc46454cce27ccfad532cedad9c"
        }
      ],
      "title": "smb: smbdirect: destroy QP before mem pools on accept failure",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-90172",
    "datePublished": "2026-09-17T16:06:59.794Z",
    "dateReserved": "2026-09-11T19:38:34.791Z",
    "dateUpdated": "2026-09-18T17:53:32.077Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}