CVE-2024-35794

2024-05-1713:15:59

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

web.nvd.nist.gov

linux kernel

vulnerability

resolved

dm-raid

sync_thread

suspend

ext4

deadlock

6.6 Medium

AI Score

Confidence

Low

0.0004 Low

EPSS

Percentile

15.5%

JSON

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

dm-raid: really frozen sync_thread during suspend

commit f52f5c71f3d4 (“md: fix stopping sync thread”) remove
MD_RECOVERY_FROZEN from __md_stop_writes() and doesn’t realize that
dm-raid relies on __md_stop_writes() to frozen sync_thread
indirectly. Fix this problem by adding MD_RECOVERY_FROZEN in
md_stop_writes(), and since stop_sync_thread() is only used for
dm-raid in this case, also move stop_sync_thread() to
md_stop_writes().
The flag MD_RECOVERY_FROZEN doesn’t mean that sync thread is frozen,
it only prevent new sync_thread to start, and it can’t stop the
running sync thread; In order to frozen sync_thread, after seting the
flag, stop_sync_thread() should be used.
The flag MD_RECOVERY_FROZEN doesn’t mean that writes are stopped, use
it as condition for md_stop_writes() in raid_postsuspend() doesn’t
look correct. Consider that reentrant stop_sync_thread() do nothing,
always call md_stop_writes() in raid_postsuspend().
raid_message can set/clear the flag MD_RECOVERY_FROZEN at anytime,
and if MD_RECOVERY_FROZEN is cleared while the array is suspended,
new sync_thread can start unexpected. Fix this by disallow
raid_message() to change sync_thread status during suspend.

Note that after commit f52f5c71f3d4 (“md: fix stopping sync thread”), the
test shell/lvconvert-raid-reshape.sh start to hang in stop_sync_thread(),
and with previous fixes, the test won’t hang there anymore, however, the
test will still fail and complain that ext4 is corrupted. And with this
patch, the test won’t hang due to stop_sync_thread() or fail due to ext4
is corrupted anymore. However, there is still a deadlock related to
dm-raid456 that will be fixed in following patches.

Affected configurations

Vulners

Node

linuxlinux_kernelRange4.8–6.7.12

linuxlinux_kernelRange6.8.0–6.8.3

linuxlinux_kernelRange6.9.0≥

VendorProductVersionCPE
linuxlinux_kernel*cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linuxlinux_kernel*cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linuxlinux_kernel*cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

Vendor	Product	Version	CPE
linux	linux_kernel	*	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	*	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	*	cpe:2.3:o:linux:linux_kernel::::::::

CNA Affected

[
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "unaffected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "drivers/md/dm-raid.c",
      "drivers/md/md.c"
    ],
    "versions": [
      {
        "version": "9dbd1aa3a81c",
        "lessThan": "af916cb66a80",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "9dbd1aa3a81c",
        "lessThan": "eaa8fc9b0928",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "9dbd1aa3a81c",
        "lessThan": "16c4770c75b1",
        "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/md/dm-raid.c",
      "drivers/md/md.c"
    ],
    "versions": [
      {
        "version": "4.8",
        "status": "affected"
      },
      {
        "version": "0",
        "lessThan": "4.8",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.7.12",
        "lessThanOrEqual": "6.7.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.8.3",
        "lessThanOrEqual": "6.8.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.9",
        "lessThanOrEqual": "*",
        "status": "unaffected",
        "versionType": "original_commit_for_fix"
      }
    ]
  }
]