CVE-2026-89483 (GCVE-0-2026-89483)
Vulnerability from cvelistv5
Published
2026-09-11 19:43
Modified
2026-10-19 08:47
Severity ?
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Summary
In the Linux kernel, the following vulnerability has been resolved: nvme: zero the discard fallback page nvme_setup_discard() always maps sizeof(struct nvme_dsm_range) * NVME_DSM_MAX_RANGES = 4096 bytes as the DSM payload however many ranges the command declares, because some devices ignore the 'Number of Ranges' field - the Fixes: commit records two that read past the declared ranges. A single-range discard fills only the first 16 bytes. Normally the buffer comes from kzalloc() and the other 4080 bytes are zero. When that allocation fails the code falls back to the per-controller ctrl->discard_page, which nvme_init_ctrl() obtains with alloc_page(GFP_KERNEL) and nothing ever zeroes, so those 4080 bytes are whatever the page last held and are handed to the controller. Reaching it requires the kzalloc(GFP_ATOMIC | __GFP_NOWARN) to fail, that is memory pressure; it is not remotely triggerable. Failing the allocation under KMSAN reproduces it, with the leaked tail full of vmemmap struct page pointers. The extent in the report is a partial transfer of the payload, not the whole 4096 bytes; the 16-byte boundary in it is the one declared range: [ 11.991601] BUG: KMSAN: uninit-value in dma_map_phys+0x14c8/0x1900 [ 11.991969] dma_map_phys+0x14c8/0x1900 [ 11.992220] dma_map_page_attrs+0xcf/0x130 [ 11.992485] e1000_xmit_frame+0x4099/0x6d10 [ 11.992768] dev_hard_start_xmit+0x22f/0xa80 [ 11.993068] sch_direct_xmit+0x35c/0xcb0 [ 11.993315] __dev_queue_xmit+0x1ee5/0x5eb0 [ 11.993608] ip_finish_output2+0x1903/0x1c30 [ 11.993881] ip_finish_output+0x288/0x870 [ 11.994125] ip_output+0x15e/0x400 [ 11.994365] __ip_queue_xmit+0x1e85/0x1fb0 [ 11.994639] ip_queue_xmit+0x60/0x80 [ 11.994899] __tcp_transmit_skb+0x4e71/0x5fa0 [ 11.995210] tcp_write_xmit+0x3a36/0x9160 [ 11.995533] __tcp_push_pending_frames+0xc5/0x3c0 [ 11.995854] tcp_push+0x7dc/0x840 [ 11.996076] tcp_sendmsg_locked+0x766c/0x8400 [ 11.996371] tcp_sendmsg+0x4b/0x90 [ 11.996572] inet_sendmsg+0x134/0x2a0 [ 11.996823] __sock_sendmsg+0x265/0x360 [ 11.997076] sock_sendmsg+0x100/0x1e0 [ 11.997293] nvme_tcp_try_send+0x196f/0x6370 [ 11.997605] nvme_tcp_queue_rq+0x1d54/0x20b0 [ 11.997882] blk_mq_dispatch_rq_list+0x5ee/0x2e50 [ 11.998175] __blk_mq_sched_dispatch_requests+0x16dc/0x24a0 [ 11.998539] blk_mq_sched_dispatch_requests+0x11b/0x2c0 [ 11.998865] blk_mq_run_work_fn+0x13b/0x280 [ 11.999146] process_scheduled_works+0x966/0x1ad0 [ 11.999465] worker_thread+0xe44/0x1480 [ 11.999709] kthread+0x53b/0x600 [ 11.999927] ret_from_fork+0x29f/0x7c0 [ 12.000191] ret_from_fork_asm+0x1a/0x30 [ 12.000460] [ 12.000558] Uninit was created at: [ 12.000788] __alloc_frozen_pages_noprof+0x8bf/0xd30 [ 12.001096] alloc_pages_mpol+0x1d0/0x5f0 [ 12.001326] alloc_pages_noprof+0x102/0x290 [ 12.001627] nvme_init_ctrl+0x5a3/0x9f0 [ 12.001891] nvme_tcp_create_ctrl+0xd75/0x19b0 [ 12.002170] nvmf_dev_write+0x4c68/0x4fd0 [ 12.002426] vfs_write+0x587/0x1a10 [ 12.002636] __x64_sys_write+0x207/0x4f0 [ 12.002874] x64_sys_call+0x2ff0/0x3ea0 [ 12.003123] do_syscall_64+0x147/0x3b0 [ 12.003400] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 12.003680] [ 12.003777] Bytes 16-2843 of 2844 are uninitialized [ 12.004068] Memory access of size 2844 starts at ffff888109f82000 [ 12.004412] [ 12.004530] CPU: 0 UID: 0 PID: 101 Comm: kworker/0:1H Not tainted 7.2.0-rc5-NVMECTL-gf5098b6bae76 #1 PREEMPT(lazy) [ 12.005127] 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 [ 12.005762] Workqueue: kblockd blk_mq_run_work_fn [ 12.006073] ===================================================== Allocate the page with __GFP_ZERO. The single allocation site covers every use of it: bytes no discard has written stay zero, and bytes one did write hold that controller's own range list, which it has already been sent.
References
Impacted products
Vendor Product Version
Linux Linux Version: 530436c45ef2e446c12538a400e465929a0b3ade
Version: 530436c45ef2e446c12538a400e465929a0b3ade
Version: 530436c45ef2e446c12538a400e465929a0b3ade
Version: 530436c45ef2e446c12538a400e465929a0b3ade
Version: 530436c45ef2e446c12538a400e465929a0b3ade
Version: 530436c45ef2e446c12538a400e465929a0b3ade
Version: 530436c45ef2e446c12538a400e465929a0b3ade
Version: 530436c45ef2e446c12538a400e465929a0b3ade
Version: ffa56cbdd2409b522b4cb56461bea1c45889417b
Version: 8b0acb768a06083b0d28bace1481c1f6679e76f4
Version: 4.19.92   ≤
Version: 5.4.7   ≤
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      "descriptions": [
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          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnvme: zero the discard fallback page\n\nnvme_setup_discard() always maps sizeof(struct nvme_dsm_range) *\nNVME_DSM_MAX_RANGES = 4096 bytes as the DSM payload however many ranges\nthe command declares, because some devices ignore the \u0027Number of Ranges\u0027\nfield - the Fixes: commit records two that read past the declared ranges.\nA single-range discard fills only the first 16 bytes.\n\nNormally the buffer comes from kzalloc() and the other 4080 bytes are\nzero.  When that allocation fails the code falls back to the\nper-controller ctrl-\u003ediscard_page, which nvme_init_ctrl() obtains with\nalloc_page(GFP_KERNEL) and nothing ever zeroes, so those 4080 bytes are\nwhatever the page last held and are handed to the controller.  Reaching\nit requires the kzalloc(GFP_ATOMIC | __GFP_NOWARN) to fail, that is\nmemory pressure; it is not remotely triggerable.  Failing the allocation\nunder KMSAN reproduces it, with the leaked tail full of vmemmap struct\npage pointers.  The extent in the report is a partial transfer of the\npayload, not the whole 4096 bytes; the 16-byte boundary in it is the one\ndeclared range:\n\n[   11.991601] BUG: KMSAN: uninit-value in dma_map_phys+0x14c8/0x1900\n[   11.991969]  dma_map_phys+0x14c8/0x1900\n[   11.992220]  dma_map_page_attrs+0xcf/0x130\n[   11.992485]  e1000_xmit_frame+0x4099/0x6d10\n[   11.992768]  dev_hard_start_xmit+0x22f/0xa80\n[   11.993068]  sch_direct_xmit+0x35c/0xcb0\n[   11.993315]  __dev_queue_xmit+0x1ee5/0x5eb0\n[   11.993608]  ip_finish_output2+0x1903/0x1c30\n[   11.993881]  ip_finish_output+0x288/0x870\n[   11.994125]  ip_output+0x15e/0x400\n[   11.994365]  __ip_queue_xmit+0x1e85/0x1fb0\n[   11.994639]  ip_queue_xmit+0x60/0x80\n[   11.994899]  __tcp_transmit_skb+0x4e71/0x5fa0\n[   11.995210]  tcp_write_xmit+0x3a36/0x9160\n[   11.995533]  __tcp_push_pending_frames+0xc5/0x3c0\n[   11.995854]  tcp_push+0x7dc/0x840\n[   11.996076]  tcp_sendmsg_locked+0x766c/0x8400\n[   11.996371]  tcp_sendmsg+0x4b/0x90\n[   11.996572]  inet_sendmsg+0x134/0x2a0\n[   11.996823]  __sock_sendmsg+0x265/0x360\n[   11.997076]  sock_sendmsg+0x100/0x1e0\n[   11.997293]  nvme_tcp_try_send+0x196f/0x6370\n[   11.997605]  nvme_tcp_queue_rq+0x1d54/0x20b0\n[   11.997882]  blk_mq_dispatch_rq_list+0x5ee/0x2e50\n[   11.998175]  __blk_mq_sched_dispatch_requests+0x16dc/0x24a0\n[   11.998539]  blk_mq_sched_dispatch_requests+0x11b/0x2c0\n[   11.998865]  blk_mq_run_work_fn+0x13b/0x280\n[   11.999146]  process_scheduled_works+0x966/0x1ad0\n[   11.999465]  worker_thread+0xe44/0x1480\n[   11.999709]  kthread+0x53b/0x600\n[   11.999927]  ret_from_fork+0x29f/0x7c0\n[   12.000191]  ret_from_fork_asm+0x1a/0x30\n[   12.000460]\n[   12.000558] Uninit was created at:\n[   12.000788]  __alloc_frozen_pages_noprof+0x8bf/0xd30\n[   12.001096]  alloc_pages_mpol+0x1d0/0x5f0\n[   12.001326]  alloc_pages_noprof+0x102/0x290\n[   12.001627]  nvme_init_ctrl+0x5a3/0x9f0\n[   12.001891]  nvme_tcp_create_ctrl+0xd75/0x19b0\n[   12.002170]  nvmf_dev_write+0x4c68/0x4fd0\n[   12.002426]  vfs_write+0x587/0x1a10\n[   12.002636]  __x64_sys_write+0x207/0x4f0\n[   12.002874]  x64_sys_call+0x2ff0/0x3ea0\n[   12.003123]  do_syscall_64+0x147/0x3b0\n[   12.003400]  entry_SYSCALL_64_after_hwframe+0x77/0x7f\n[   12.003680]\n[   12.003777] Bytes 16-2843 of 2844 are uninitialized\n[   12.004068] Memory access of size 2844 starts at ffff888109f82000\n[   12.004412]\n[   12.004530] CPU: 0 UID: 0 PID: 101 Comm: kworker/0:1H Not tainted 7.2.0-rc5-NVMECTL-gf5098b6bae76 #1 PREEMPT(lazy)\n[   12.005127] 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[   12.005762] Workqueue: kblockd blk_mq_run_work_fn\n[   12.006073] =====================================================\n\nAllocate the page with __GFP_ZERO.  The single allocation site covers\nevery use of it: bytes no discard has written stay zero, and bytes one\ndid write hold that controller\u0027s own range list, which it has already\nbeen sent."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7.5,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:N - nvme_setup_discard() DMA-maps a 4096-byte DSM buffer that nvme-tcp (KMSAN: nvme_tcp_try_send), nvme-rdma, and nvme-fc transmit to the remote controller, so a malicious NVMe-oF target on the storage fabric receives the leftover kernel page.\nAC:L - The fallback is used when kzalloc(GFP_ATOMIC|__GFP_NOWARN) fails; a fabric peer can drive watermarks with high queue-depth I/O while discards run and retry until discard_page is used, with no race or unknown layout required.\nPR:N - A compromised NVMe-oF target needs no Linux account or capability on the initiator; once the host is attached to fabric storage, DSM payloads are sent without further local authorization.\nUI:N - REQ_OP_DISCARD is issued automatically by mount-discard, fstrim timers, hole-punch, and thin-provision UNMAP during normal operation once an NVMe controller exists; no extra victim mount or click is required at exploit time.\nS:U - The disclosure is host kernel memory to the NVMe controller/peer within the same kernel authority and is not a VM escape, IOMMU bypass, or other cross-boundary scope change.\nC:H - nvme_init_ctrl() allocated discard_page with alloc_page(GFP_KERNEL) and no __GFP_ZERO, so up to 4080 bytes of stale buddy-page contents (KMSAN showed kernel/vmemmap pointers) are sent in the DSM payload, a page-sized leak rather than a few bounded bytes.\nI:N - The flaw only transmits leftover page bytes to the controller; it does not overwrite kernel objects, provide a write primitive, or enable control-flow hijacking.\nA:N - DMA/send of the uninitialized DSM padding completes without oops, panic, or hang; the KMSAN uninit-value report is a sanitizer finding on the transmit path, not a host denial of service."
            }
          ]
        }
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      "providerMetadata": {
        "dateUpdated": "2026-10-19T08:47:33.684Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
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      "references": [
        {
          "url": "https://git.kernel.org/stable/c/76139b5bbf531e675934b97227be3521c7fdd537"
        },
        {
          "url": "https://git.kernel.org/stable/c/3f84d2bd0d8ae8c7e8e0f8fc3cbf018a282971a1"
        },
        {
          "url": "https://git.kernel.org/stable/c/415f2772ebcbc7f3f1ab1a71915dab82cee3465e"
        },
        {
          "url": "https://git.kernel.org/stable/c/66b5af23b6f956e57f8205c46aa80b054631be34"
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        {
          "url": "https://git.kernel.org/stable/c/bededeaaeff404978a5a8e2a605a6c3017cddd3e"
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      ],
      "title": "nvme: zero the discard fallback page",
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    "assignerShortName": "Linux",
    "cveId": "CVE-2026-89483",
    "datePublished": "2026-09-11T19:43:38.076Z",
    "dateReserved": "2026-09-11T19:38:34.712Z",
    "dateUpdated": "2026-10-19T08:47:33.684Z",
    "state": "PUBLISHED"
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  "vulnerability-lookup:meta": {
    "vulnrichment": {
      "containers": "{\"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-89483\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"none\"}, {\"Automatable\": \"yes\"}, {\"Technical Impact\": \"partial\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-10-16T19:22:40.450387Z\"}}}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2026-10-16T19:22:41.411Z\"}}], \"cna\": {\"title\": \"nvme: zero the discard fallback page\", \"metrics\": [{\"cvssV3_1\": {\"version\": \"3.1\", \"baseScore\": 7.5, \"baseSeverity\": \"HIGH\", \"vectorString\": \"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N\"}, \"scenarios\": [{\"lang\": \"en\", \"value\": \"AV:N - nvme_setup_discard() DMA-maps a 4096-byte DSM buffer that nvme-tcp (KMSAN: nvme_tcp_try_send), nvme-rdma, and nvme-fc transmit to the remote controller, so a malicious NVMe-oF target on the storage fabric receives the leftover kernel page.\\nAC:L - The fallback is used when kzalloc(GFP_ATOMIC|__GFP_NOWARN) fails; a fabric peer can drive watermarks with high queue-depth I/O while discards run and retry until discard_page is used, with no race or unknown layout required.\\nPR:N - A compromised NVMe-oF target needs no Linux account or capability on the initiator; once the host is attached to fabric storage, DSM payloads are sent without further local authorization.\\nUI:N - REQ_OP_DISCARD is issued automatically by mount-discard, fstrim timers, hole-punch, and thin-provision UNMAP during normal operation once an NVMe controller exists; no extra victim mount or click is required at exploit time.\\nS:U - The disclosure is host kernel memory to the NVMe controller/peer within the same kernel authority and is not a VM escape, IOMMU bypass, or other cross-boundary scope change.\\nC:H - nvme_init_ctrl() allocated discard_page with alloc_page(GFP_KERNEL) and no __GFP_ZERO, so up to 4080 bytes of stale buddy-page contents (KMSAN showed kernel/vmemmap pointers) are sent in the DSM payload, a page-sized leak rather than a few bounded bytes.\\nI:N - The flaw only transmits leftover page bytes to the controller; it does not overwrite kernel objects, provide a write primitive, or enable control-flow hijacking.\\nA:N - DMA/send of the uninitialized DSM padding completes without oops, panic, or hang; the KMSAN uninit-value report is a sanitizer finding on the transmit path, not a host denial of service.\"}]}], \"affected\": [{\"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\", \"vendor\": \"Linux\", \"product\": \"Linux\", \"versions\": [{\"status\": \"affected\", \"version\": \"530436c45ef2e446c12538a400e465929a0b3ade\", \"lessThan\": \"76139b5bbf531e675934b97227be3521c7fdd537\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"530436c45ef2e446c12538a400e465929a0b3ade\", \"lessThan\": \"3f84d2bd0d8ae8c7e8e0f8fc3cbf018a282971a1\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"530436c45ef2e446c12538a400e465929a0b3ade\", \"lessThan\": \"415f2772ebcbc7f3f1ab1a71915dab82cee3465e\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"530436c45ef2e446c12538a400e465929a0b3ade\", \"lessThan\": \"66b5af23b6f956e57f8205c46aa80b054631be34\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"530436c45ef2e446c12538a400e465929a0b3ade\", \"lessThan\": \"dc4d4b70a863f7e39ef8bd137634be4e6db8b084\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"530436c45ef2e446c12538a400e465929a0b3ade\", \"lessThan\": \"67551d8430df94c827e1830bd3a5fae1f66a5219\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"530436c45ef2e446c12538a400e465929a0b3ade\", \"lessThan\": \"f5827817b4fc7feeabf4f53fb4b626e6edc52fef\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"530436c45ef2e446c12538a400e465929a0b3ade\", \"lessThan\": \"bededeaaeff404978a5a8e2a605a6c3017cddd3e\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"ffa56cbdd2409b522b4cb56461bea1c45889417b\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"8b0acb768a06083b0d28bace1481c1f6679e76f4\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"4.19.92\", \"lessThan\": \"4.20\", \"versionType\": \"semver\"}, {\"status\": \"affected\", \"version\": \"5.4.7\", \"lessThan\": \"5.5\", \"versionType\": \"semver\"}], \"programFiles\": [\"drivers/nvme/host/core.c\"], \"defaultStatus\": \"unaffected\"}, {\"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\", \"vendor\": \"Linux\", \"product\": \"Linux\", \"versions\": [{\"status\": \"affected\", \"version\": \"5.5\"}, {\"status\": \"unaffected\", \"version\": \"0\", \"lessThan\": \"5.5\", \"versionType\": \"semver\"}, {\"status\": \"unaffected\", \"version\": \"5.10.270\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"5.10.*\"}, {\"status\": \"unaffected\", \"version\": \"5.15.221\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"5.15.*\"}, {\"status\": \"unaffected\", \"version\": \"6.1.188\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"6.1.*\"}, {\"status\": \"unaffected\", \"version\": \"6.6.157\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"6.6.*\"}, {\"status\": \"unaffected\", \"version\": \"6.12.109\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"6.12.*\"}, {\"status\": \"unaffected\", \"version\": \"6.18.50\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"6.18.*\"}, {\"status\": \"unaffected\", \"version\": \"7.2.4\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"7.2.*\"}, {\"status\": \"unaffected\", \"version\": \"7.3\", \"versionType\": \"original_commit_for_fix\", \"lessThanOrEqual\": \"*\"}], \"programFiles\": [\"drivers/nvme/host/core.c\"], \"defaultStatus\": \"affected\"}], \"references\": [{\"url\": \"https://git.kernel.org/stable/c/76139b5bbf531e675934b97227be3521c7fdd537\"}, {\"url\": \"https://git.kernel.org/stable/c/3f84d2bd0d8ae8c7e8e0f8fc3cbf018a282971a1\"}, {\"url\": \"https://git.kernel.org/stable/c/415f2772ebcbc7f3f1ab1a71915dab82cee3465e\"}, {\"url\": \"https://git.kernel.org/stable/c/66b5af23b6f956e57f8205c46aa80b054631be34\"}, {\"url\": \"https://git.kernel.org/stable/c/dc4d4b70a863f7e39ef8bd137634be4e6db8b084\"}, {\"url\": \"https://git.kernel.org/stable/c/67551d8430df94c827e1830bd3a5fae1f66a5219\"}, {\"url\": \"https://git.kernel.org/stable/c/f5827817b4fc7feeabf4f53fb4b626e6edc52fef\"}, {\"url\": \"https://git.kernel.org/stable/c/bededeaaeff404978a5a8e2a605a6c3017cddd3e\"}], \"x_generator\": {\"engine\": \"bippy-1.2.0\"}, \"descriptions\": [{\"lang\": \"en\", \"value\": \"In the Linux kernel, the following vulnerability has been resolved:\\n\\nnvme: zero the discard fallback page\\n\\nnvme_setup_discard() always maps sizeof(struct nvme_dsm_range) *\\nNVME_DSM_MAX_RANGES = 4096 bytes as the DSM payload however many ranges\\nthe command declares, because some devices ignore the \u0027Number of Ranges\u0027\\nfield - the Fixes: commit records two that read past the declared ranges.\\nA single-range discard fills only the first 16 bytes.\\n\\nNormally the buffer comes from kzalloc() and the other 4080 bytes are\\nzero.  When that allocation fails the code falls back to the\\nper-controller ctrl-\u003ediscard_page, which nvme_init_ctrl() obtains with\\nalloc_page(GFP_KERNEL) and nothing ever zeroes, so those 4080 bytes are\\nwhatever the page last held and are handed to the controller.  Reaching\\nit requires the kzalloc(GFP_ATOMIC | __GFP_NOWARN) to fail, that is\\nmemory pressure; it is not remotely triggerable.  Failing the allocation\\nunder KMSAN reproduces it, with the leaked tail full of vmemmap struct\\npage pointers.  The extent in the report is a partial transfer of the\\npayload, not the whole 4096 bytes; the 16-byte boundary in it is the one\\ndeclared range:\\n\\n[   11.991601] BUG: KMSAN: uninit-value in dma_map_phys+0x14c8/0x1900\\n[   11.991969]  dma_map_phys+0x14c8/0x1900\\n[   11.992220]  dma_map_page_attrs+0xcf/0x130\\n[   11.992485]  e1000_xmit_frame+0x4099/0x6d10\\n[   11.992768]  dev_hard_start_xmit+0x22f/0xa80\\n[   11.993068]  sch_direct_xmit+0x35c/0xcb0\\n[   11.993315]  __dev_queue_xmit+0x1ee5/0x5eb0\\n[   11.993608]  ip_finish_output2+0x1903/0x1c30\\n[   11.993881]  ip_finish_output+0x288/0x870\\n[   11.994125]  ip_output+0x15e/0x400\\n[   11.994365]  __ip_queue_xmit+0x1e85/0x1fb0\\n[   11.994639]  ip_queue_xmit+0x60/0x80\\n[   11.994899]  __tcp_transmit_skb+0x4e71/0x5fa0\\n[   11.995210]  tcp_write_xmit+0x3a36/0x9160\\n[   11.995533]  __tcp_push_pending_frames+0xc5/0x3c0\\n[   11.995854]  tcp_push+0x7dc/0x840\\n[   11.996076]  tcp_sendmsg_locked+0x766c/0x8400\\n[   11.996371]  tcp_sendmsg+0x4b/0x90\\n[   11.996572]  inet_sendmsg+0x134/0x2a0\\n[   11.996823]  __sock_sendmsg+0x265/0x360\\n[   11.997076]  sock_sendmsg+0x100/0x1e0\\n[   11.997293]  nvme_tcp_try_send+0x196f/0x6370\\n[   11.997605]  nvme_tcp_queue_rq+0x1d54/0x20b0\\n[   11.997882]  blk_mq_dispatch_rq_list+0x5ee/0x2e50\\n[   11.998175]  __blk_mq_sched_dispatch_requests+0x16dc/0x24a0\\n[   11.998539]  blk_mq_sched_dispatch_requests+0x11b/0x2c0\\n[   11.998865]  blk_mq_run_work_fn+0x13b/0x280\\n[   11.999146]  process_scheduled_works+0x966/0x1ad0\\n[   11.999465]  worker_thread+0xe44/0x1480\\n[   11.999709]  kthread+0x53b/0x600\\n[   11.999927]  ret_from_fork+0x29f/0x7c0\\n[   12.000191]  ret_from_fork_asm+0x1a/0x30\\n[   12.000460]\\n[   12.000558] Uninit was created at:\\n[   12.000788]  __alloc_frozen_pages_noprof+0x8bf/0xd30\\n[   12.001096]  alloc_pages_mpol+0x1d0/0x5f0\\n[   12.001326]  alloc_pages_noprof+0x102/0x290\\n[   12.001627]  nvme_init_ctrl+0x5a3/0x9f0\\n[   12.001891]  nvme_tcp_create_ctrl+0xd75/0x19b0\\n[   12.002170]  nvmf_dev_write+0x4c68/0x4fd0\\n[   12.002426]  vfs_write+0x587/0x1a10\\n[   12.002636]  __x64_sys_write+0x207/0x4f0\\n[   12.002874]  x64_sys_call+0x2ff0/0x3ea0\\n[   12.003123]  do_syscall_64+0x147/0x3b0\\n[   12.003400]  entry_SYSCALL_64_after_hwframe+0x77/0x7f\\n[   12.003680]\\n[   12.003777] Bytes 16-2843 of 2844 are uninitialized\\n[   12.004068] Memory access of size 2844 starts at ffff888109f82000\\n[   12.004412]\\n[   12.004530] CPU: 0 UID: 0 PID: 101 Comm: kworker/0:1H Not tainted 7.2.0-rc5-NVMECTL-gf5098b6bae76 #1 PREEMPT(lazy)\\n[   12.005127] 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[   12.005762] Workqueue: kblockd blk_mq_run_work_fn\\n[   12.006073] =====================================================\\n\\nAllocate the page with __GFP_ZERO.  The single allocation site covers\\nevery use of it: bytes no discard has written stay zero, and bytes one\\ndid write hold that controller\u0027s own range list, which it has already\\nbeen sent.\"}], \"cpeApplicability\": [{\"nodes\": [{\"negate\": false, \"cpeMatch\": [{\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"5.10.270\", \"versionStartIncluding\": \"5.5\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"5.15.221\", \"versionStartIncluding\": \"5.5\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"6.1.188\", \"versionStartIncluding\": \"5.5\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"6.6.157\", \"versionStartIncluding\": \"5.5\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"6.12.109\", \"versionStartIncluding\": \"5.5\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"6.18.50\", \"versionStartIncluding\": \"5.5\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"7.2.4\", \"versionStartIncluding\": \"5.5\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"7.3\", \"versionStartIncluding\": \"5.5\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionStartIncluding\": \"4.19.92\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionStartIncluding\": \"5.4.7\"}], \"operator\": \"OR\"}]}], \"providerMetadata\": {\"orgId\": \"416baaa9-dc9f-4396-8d5f-8c081fb06d67\", \"shortName\": \"Linux\", \"dateUpdated\": \"2026-10-19T08:47:33.684Z\"}}}",
      "cveMetadata": "{\"cveId\": \"CVE-2026-89483\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-10-19T08:47:33.684Z\", \"dateReserved\": \"2026-09-11T19:38:34.712Z\", \"assignerOrgId\": \"416baaa9-dc9f-4396-8d5f-8c081fb06d67\", \"datePublished\": \"2026-09-11T19:43:38.076Z\", \"assignerShortName\": \"Linux\"}",
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}


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  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
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