CVE-2021-47237

2024-05-2115:15:12

416baaa9-dc9f-4396-8d5f-8c081fb06d67

web.nvd.nist.gov

linux kernel

memory leak

net: hamradio

mkiss_close

vulnerability

6.5 Medium

AI Score

Confidence

Low

0.0004 Low

EPSS

Percentile

13.1%

JSON

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

net: hamradio: fix memory leak in mkiss_close

My local syzbot instance hit memory leak in
mkiss_open()[1]. The problem was in missing
free_netdev() in mkiss_close().

In mkiss_open() netdevice is allocated and then
registered, but in mkiss_close() netdevice was
only unregistered, but not freed.

Fail log:

BUG: memory leak
unreferenced object 0xffff8880281ba000 (size 4096):
comm “syz-executor.1”, pid 11443, jiffies 4295046091 (age 17.660s)
hex dump (first 32 bytes):
61 78 30 00 00 00 00 00 00 00 00 00 00 00 00 00 ax0…
00 27 fa 2a 80 88 ff ff 00 00 00 00 00 00 00 00 .'.*…
backtrace:
[<ffffffff81a27201>] kvmalloc_node+0x61/0xf0
[<ffffffff8706e7e8>] alloc_netdev_mqs+0x98/0xe80
[<ffffffff84e64192>] mkiss_open+0xb2/0x6f0 [1]
[<ffffffff842355db>] tty_ldisc_open+0x9b/0x110
[<ffffffff84236488>] tty_set_ldisc+0x2e8/0x670
[<ffffffff8421f7f3>] tty_ioctl+0xda3/0x1440
[<ffffffff81c9f273>] __x64_sys_ioctl+0x193/0x200
[<ffffffff8911263a>] do_syscall_64+0x3a/0xb0
[<ffffffff89200068>] entry_SYSCALL_64_after_hwframe+0x44/0xae

BUG: memory leak
unreferenced object 0xffff8880141a9a00 (size 96):
comm “syz-executor.1”, pid 11443, jiffies 4295046091 (age 17.660s)
hex dump (first 32 bytes):
e8 a2 1b 28 80 88 ff ff e8 a2 1b 28 80 88 ff ff …(…(…
98 92 9c aa b0 40 02 00 00 00 00 00 00 00 00 00 …@…
backtrace:
[<ffffffff8709f68b>] __hw_addr_create_ex+0x5b/0x310
[<ffffffff8709fb38>] __hw_addr_add_ex+0x1f8/0x2b0
[<ffffffff870a0c7b>] dev_addr_init+0x10b/0x1f0
[<ffffffff8706e88b>] alloc_netdev_mqs+0x13b/0xe80
[<ffffffff84e64192>] mkiss_open+0xb2/0x6f0 [1]
[<ffffffff842355db>] tty_ldisc_open+0x9b/0x110
[<ffffffff84236488>] tty_set_ldisc+0x2e8/0x670
[<ffffffff8421f7f3>] tty_ioctl+0xda3/0x1440
[<ffffffff81c9f273>] __x64_sys_ioctl+0x193/0x200
[<ffffffff8911263a>] do_syscall_64+0x3a/0xb0
[<ffffffff89200068>] entry_SYSCALL_64_after_hwframe+0x44/0xae

BUG: memory leak
unreferenced object 0xffff8880219bfc00 (size 512):
comm “syz-executor.1”, pid 11443, jiffies 4295046091 (age 17.660s)
hex dump (first 32 bytes):
00 a0 1b 28 80 88 ff ff 80 8f b1 8d ff ff ff ff …(…
80 8f b1 8d ff ff ff ff 00 00 00 00 00 00 00 00 …
backtrace:
[<ffffffff81a27201>] kvmalloc_node+0x61/0xf0
[<ffffffff8706eec7>] alloc_netdev_mqs+0x777/0xe80
[<ffffffff84e64192>] mkiss_open+0xb2/0x6f0 [1]
[<ffffffff842355db>] tty_ldisc_open+0x9b/0x110
[<ffffffff84236488>] tty_set_ldisc+0x2e8/0x670
[<ffffffff8421f7f3>] tty_ioctl+0xda3/0x1440
[<ffffffff81c9f273>] __x64_sys_ioctl+0x193/0x200
[<ffffffff8911263a>] do_syscall_64+0x3a/0xb0
[<ffffffff89200068>] entry_SYSCALL_64_after_hwframe+0x44/0xae

BUG: memory leak
unreferenced object 0xffff888029b2b200 (size 256):
comm “syz-executor.1”, pid 11443, jiffies 4295046091 (age 17.660s)
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 …
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 …
backtrace:
[<ffffffff81a27201>] kvmalloc_node+0x61/0xf0
[<ffffffff8706f062>] alloc_netdev_mqs+0x912/0xe80
[<ffffffff84e64192>] mkiss_open+0xb2/0x6f0 [1]
[<ffffffff842355db>] tty_ldisc_open+0x9b/0x110
[<ffffffff84236488>] tty_set_ldisc+0x2e8/0x670
[<ffffffff8421f7f3>] tty_ioctl+0xda3/0x1440
[<ffffffff81c9f273>] __x64_sys_ioctl+0x193/0x200
[<ffffffff8911263a>] do_syscall_64+0x3a/0xb0
[<ffffffff89200068>] entry_SYSCALL_64_after_hwframe+0x44/0xae

Affected configurations

Vulners

Node

linuxlinux_kernelRange2.6.14–4.4.274

linuxlinux_kernelRange4.5.0–4.9.274

linuxlinux_kernelRange4.10.0–4.14.238

linuxlinux_kernelRange4.15.0–4.19.196

linuxlinux_kernelRange4.20.0–5.4.128

linuxlinux_kernelRange5.5.0–5.10.46

linuxlinux_kernelRange5.11.0–5.12.13

linuxlinux_kernelRange5.13.0≥

CNA Affected

[
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "unaffected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "drivers/net/hamradio/mkiss.c"
    ],
    "versions": [
      {
        "version": "815f62bf7427",
        "lessThan": "c634ba0b4159",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "815f62bf7427",
        "lessThan": "3942d0f9ace1",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "815f62bf7427",
        "lessThan": "765a8a04f828",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "815f62bf7427",
        "lessThan": "c16c4716a1b5",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "815f62bf7427",
        "lessThan": "a49cbb762ef2",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "815f62bf7427",
        "lessThan": "290b0b6432e2",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "815f62bf7427",
        "lessThan": "f4de2b43d13b",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "815f62bf7427",
        "lessThan": "7edcc6823014",
        "status": "affected",
        "versionType": "git"
      }
    ]
  },
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "affected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "drivers/net/hamradio/mkiss.c"
    ],
    "versions": [
      {
        "version": "2.6.14",
        "status": "affected"
      },
      {
        "version": "0",
        "lessThan": "2.6.14",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "4.4.274",
        "lessThanOrEqual": "4.4.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "4.9.274",
        "lessThanOrEqual": "4.9.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "4.14.238",
        "lessThanOrEqual": "4.14.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "4.19.196",
        "lessThanOrEqual": "4.19.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.4.128",
        "lessThanOrEqual": "5.4.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.10.46",
        "lessThanOrEqual": "5.10.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.12.13",
        "lessThanOrEqual": "5.12.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.13",
        "lessThanOrEqual": "*",
        "status": "unaffected",
        "versionType": "original_commit_for_fix"
      }
    ]
  }
]