CVE-2024-46679 ethtool: check device is present when getting link settings

2024-09-1305:29:13

Linux

www.cve.org

linux kernel

ethtool

vulnerability

sysfs reader

device reset

device removal

panic

net-sysfs

device presence check

EPSS

Percentile

10.9%

JSON

In the Linux kernel, the following vulnerability has been resolved:

ethtool: check device is present when getting link settings

A sysfs reader can race with a device reset or removal, attempting to
read device state when the device is not actually present. eg:

 [exception RIP: qed_get_current_link+17]

#8 [ffffb9e4f2907c48] qede_get_link_ksettings at ffffffffc07a994a [qede]
#9 [ffffb9e4f2907cd8] __rh_call_get_link_ksettings at ffffffff992b01a3
#10 [ffffb9e4f2907d38] __ethtool_get_link_ksettings at ffffffff992b04e4
#11 [ffffb9e4f2907d90] duplex_show at ffffffff99260300
#12 [ffffb9e4f2907e38] dev_attr_show at ffffffff9905a01c
#13 [ffffb9e4f2907e50] sysfs_kf_seq_show at ffffffff98e0145b
#14 [ffffb9e4f2907e68] seq_read at ffffffff98d902e3
#15 [ffffb9e4f2907ec8] vfs_read at ffffffff98d657d1
#16 [ffffb9e4f2907f00] ksys_read at ffffffff98d65c3f
#17 [ffffb9e4f2907f38] do_syscall_64 at ffffffff98a052fb

crash> struct net_device.state ffff9a9d21336000
state = 5,

state 5 is __LINK_STATE_START (0b1) and __LINK_STATE_NOCARRIER (0b100).
The device is not present, note lack of __LINK_STATE_PRESENT (0b10).

This is the same sort of panic as observed in commit 4224cfd7fb65
(“net-sysfs: add check for netdevice being present to speed_show”).

There are many other callers of __ethtool_get_link_ksettings() which
don’t have a device presence check.

Move this check into ethtool to protect all callers.

CNA Affected

[
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "unaffected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "net/core/net-sysfs.c",
      "net/ethtool/ioctl.c"
    ],
    "versions": [
      {
        "version": "d519e17e2d01",
        "lessThan": "ec7b4f7f6440",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "d519e17e2d01",
        "lessThan": "842a40c7273b",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "d519e17e2d01",
        "lessThan": "7a8d98b6d648",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "d519e17e2d01",
        "lessThan": "9bba5955eed1",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "d519e17e2d01",
        "lessThan": "94ab317024ba",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "d519e17e2d01",
        "lessThan": "1d6d9b5b1b95",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "d519e17e2d01",
        "lessThan": "a699781c79ec",
        "status": "affected",
        "versionType": "git"
      }
    ]
  },
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "affected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "net/core/net-sysfs.c",
      "net/ethtool/ioctl.c"
    ],
    "versions": [
      {
        "version": "2.6.33",
        "status": "affected"
      },
      {
        "version": "0",
        "lessThan": "2.6.33",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.4.283",
        "lessThanOrEqual": "5.4.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.10.225",
        "lessThanOrEqual": "5.10.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.15.166",
        "lessThanOrEqual": "5.15.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.1.108",
        "lessThanOrEqual": "6.1.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.6.49",
        "lessThanOrEqual": "6.6.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.10.8",
        "lessThanOrEqual": "6.10.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.11",
        "lessThanOrEqual": "*",
        "status": "unaffected",
        "versionType": "original_commit_for_fix"
      }
    ]
  }
]