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CVE-2026-89780

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: net: qualcomm: rmnet: restore skb->dev on deaggregated frames rmnet_map_deaggregate() allocates each sub-frame with alloc_skb() and leaves skb->dev NULL. __rmnet_map_ingress_handler() assigns skb->dev = ep->egress_dev only on the data path, but a MAP command frame is dispatched to rmnet_map_command() before that, so rmnet_map_send_ack() runs netif_tx_lock(skb->dev) on a NULL device. An unprivileged user reaches this by unsharing a user+net namespace, creating an rmnet link over a tap device with INGRESS_DEAGGREGATION and INGRESS_MAP_COMMANDS, and writing an aggregated frame carrying a flow-control command to the tap fd. Restore the assignment dropped by 378e25357ac7, so every skb leaving rmnet_map_deaggregate() has a valid device. BUG: KASAN: null-ptr-deref in _raw_spin_lock (kernel/locking/spinlock.c:158) Write of size 4 at addr 00000000000004b4 by task exploit/144 Call Trace: _raw_spin_lock (kernel/locking/spinlock.c:158) netif_tx_lock (net/sched/sch_generic.c:497) rmnet_map_command (drivers/net/ethernet/qualcomm/rmnet/rmnet_map_command.c:67) rmnet_rx_handler (drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c:125) __netif_receive_skb_core.constprop.0 (net/core/dev.c:6103) ... __netif_receive_skb_one_core (net/core/dev.c:6214) netif_receive_skb (net/core/dev.c:6474) tun_get_user (drivers/net/tun.c:1966) tun_chr_write_iter (drivers/net/tun.c:2012) vfs_write (fs/read_write.c:687) ksys_write (fs/read_write.c:739) do_syscall_64 (arch/x86/entry/syscall_64.c:94) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121) Kernel panic - not syncing: Fatal exception in interrupt

Severity
Not scored
CVSS score
Not available
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-09-16 09:17:08.520000
Last modified
2026-10-19 09:18:21.380000
View original CVE JSON
{
  "id": "CVE-2026-89780",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-09-16T09:17:08.520",
  "lastModified": "2026-10-19T09:18:21.380",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: qualcomm: rmnet: restore skb->dev on deaggregated frames\n\nrmnet_map_deaggregate() allocates each sub-frame with alloc_skb() and\nleaves skb->dev NULL. __rmnet_map_ingress_handler() assigns\nskb->dev = ep->egress_dev only on the data path, but a MAP command frame\nis dispatched to rmnet_map_command() before that, so rmnet_map_send_ack()\nruns netif_tx_lock(skb->dev) on a NULL device. An unprivileged user\nreaches this by unsharing a user+net namespace, creating an rmnet link\nover a tap device with INGRESS_DEAGGREGATION and INGRESS_MAP_COMMANDS,\nand writing an aggregated frame carrying a flow-control command to the\ntap fd.\n\nRestore the assignment dropped by 378e25357ac7, so every skb leaving\nrmnet_map_deaggregate() has a valid device.\n\n  BUG: KASAN: null-ptr-deref in _raw_spin_lock (kernel/locking/spinlock.c:158)\n  Write of size 4 at addr 00000000000004b4 by task exploit/144\n  Call Trace:\n   _raw_spin_lock (kernel/locking/spinlock.c:158)\n   netif_tx_lock (net/sched/sch_generic.c:497)\n   rmnet_map_command (drivers/net/ethernet/qualcomm/rmnet/rmnet_map_command.c:67)\n   rmnet_rx_handler (drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c:125)\n   __netif_receive_skb_core.constprop.0 (net/core/dev.c:6103)\n   ...\n   __netif_receive_skb_one_core (net/core/dev.c:6214)\n   netif_receive_skb (net/core/dev.c:6474)\n   tun_get_user (drivers/net/tun.c:1966)\n   tun_chr_write_iter (drivers/net/tun.c:2012)\n   vfs_write (fs/read_write.c:687)\n   ksys_write (fs/read_write.c:739)\n   do_syscall_64 (arch/x86/entry/syscall_64.c:94)\n   entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121)\n  Kernel panic - not syncing: Fatal exception in interrupt"
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "378e25357ac78ad02fbc98bec9b4e3baaa916c5c",
              "lessThan": "5aaa7409c1b4ca4c60d66e2afa99703bf4eb7ddd",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "378e25357ac78ad02fbc98bec9b4e3baaa916c5c",
              "lessThan": "9b78ab84ddf97c06a8567edb62b6c0fd582f9a62",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "378e25357ac78ad02fbc98bec9b4e3baaa916c5c",
              "lessThan": "9d18c6c6cd1666b2cb7915cad052e22abf520997",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "378e25357ac78ad02fbc98bec9b4e3baaa916c5c",
              "lessThan": "4bcef54e4a3355a62d9ad90729fe563435ec76c3",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "378e25357ac78ad02fbc98bec9b4e3baaa916c5c",
              "lessThan": "b14c22c31d9e30f38ea1693ac06d318f32258f5d",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "378e25357ac78ad02fbc98bec9b4e3baaa916c5c",
              "lessThan": "7abe769e72c792e5f9eb273813eb3ecd8389854c",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "378e25357ac78ad02fbc98bec9b4e3baaa916c5c",
              "lessThan": "200460a0793dc6af97d3b36d92ac245350ac26fc",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "378e25357ac78ad02fbc98bec9b4e3baaa916c5c",
              "lessThan": "a66734a1c5e36525ea07e9f4547fddc51e916de3",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "4.17",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "4.17",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "5.10.270",
              "lessThanOrEqual": "5.10.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "5.15.221",
              "lessThanOrEqual": "5.15.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.1.188",
              "lessThanOrEqual": "6.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.6.157",
              "lessThanOrEqual": "6.6.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.110",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.52",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.6",
              "lessThanOrEqual": "7.2.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.3",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {},
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/200460a0793dc6af97d3b36d92ac245350ac26fc",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/4bcef54e4a3355a62d9ad90729fe563435ec76c3",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/5aaa7409c1b4ca4c60d66e2afa99703bf4eb7ddd",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/7abe769e72c792e5f9eb273813eb3ecd8389854c",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/9b78ab84ddf97c06a8567edb62b6c0fd582f9a62",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/9d18c6c6cd1666b2cb7915cad052e22abf520997",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/a66734a1c5e36525ea07e9f4547fddc51e916de3",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/b14c22c31d9e30f38ea1693ac06d318f32258f5d",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}