# CVE-2022-50782: ext4: fix bug_on in __es_tree_search caused by bad quota inode

> A local attacker can cause a kernel crash by mounting a crafted ext4 filesystem with a bad quota inode.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 24 Dec 2025
- **Updated:** 11 May 2026
- **Also known as:** DEBIAN-CVE-2022-50782, GHSA-pjj6-7q87-wc4g, UBUNTU-CVE-2022-50782

## What is CVE-2022-50782?

CVE-2022-50782 is a denial of service vulnerability in Linux, published on 24 Dec 2025. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

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

ext4: fix bug_on in __es_tree_search caused by bad quota inode

We got a issue as fllows:
==================================================================
 kernel BUG at fs/ext4/extents_status.c:202!
 invalid opcode: 0000 [#1] PREEMPT SMP
 CPU: 1 PID: 810 Comm: mount Not tainted 6.1.0-rc1-next-g9631525255e3 #352
 RIP: 0010:__es_tree_search.isra.0+0xb8/0xe0
 RSP: 0018:ffffc90001227900 EFLAGS: 00010202
 RAX: 0000000000000000 RBX: 0000000077512a0f RCX: 0000000000000000
 RDX: 0000000000000002 RSI: 0000000000002a10 RDI: ffff8881004cd0c8
 RBP: ffff888177512ac8 R08: 47ffffffffffffff R09: 0000000000000001
 R10: 0000000000000001 R11: 00000000000679af R12: 0000000000002a10
 R13: ffff888177512d88 R14: 0000000077512a10 R15: 0000000000000000
 FS: 00007f4bd76dbc40(0000)GS:ffff88842fd00000(0000)knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00005653bf993cf8 CR3: 000000017bfdf000 CR4: 00000000000006e0
 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
 Call Trace:
  <TASK>
  ext4_es_cache_extent+0xe2/0x210
  ext4_cache_extents+0xd2/0x110
  ext4_find_extent+0x5d5/0x8c0
  ext4_ext_map_blocks+0x9c/0x1d30
  ext4_map_blocks+0x431/0xa50
  ext4_getblk+0x82/0x340
  ext4_bread+0x14/0x110
  ext4_quota_read+0xf0/0x180
  v2_read_header+0x24/0x90
  v2_check_quota_file+0x2f/0xa0
  dquot_load_quota_sb+0x26c/0x760
  dquot_load_quota_inode+0xa5/0x190
  ext4_enable_quotas+0x14c/0x300
  __ext4_fill_super+0x31cc/0x32c0
  ext4_fill_super+0x115/0x2d0
  get_tree_bdev+0x1d2/0x360
  ext4_get_tree+0x19/0x30
  vfs_get_tree+0x26/0xe0
  path_mount+0x81d/0xfc0
  do_mount+0x8d/0xc0
  __x64_sys_mount+0xc0/0x160
  do_syscall_64+0x35/0x80
  entry_SYSCALL_64_after_hwframe+0x63/0xcd
  </TASK>
==================================================================

Above issue may happen as follows:
-------------------------------------
ext4_fill_super
 ext4_orphan_cleanup
  ext4_enable_quotas
   ext4_quota_enable
    ext4_iget --> get error inode <5>
     ext4_ext_check_inode --> Wrong imode makes it escape inspection
     make_bad_inode(inode) --> EXT4_BOOT_LOADER_INO set imode
    dquot_load_quota_inode
     vfs_setup_quota_inode --> check pass
     dquot_load_quota_sb
      v2_check_quota_file
       v2_read_header
        ext4_quota_read
         ext4_bread
          ext4_getblk
           ext4_map_blocks
            ext4_ext_map_blocks
             ext4_find_extent
              ext4_cache_extents
               ext4_es_cache_extent
                __es_tree_search.isra.0
                 ext4_es_end --> Wrong extents trigger BUG_ON

In the above issue, s_usr_quota_inum is set to 5, but inode<5> contains
incorrect imode and disordered extents. Because 5 is EXT4_BOOT_LOADER_INO,
the ext4_ext_check_inode check in the ext4_iget function can be bypassed,
finally, the extents that are not checked trigger the BUG_ON in the
__es_tree_search function. To solve this issue, check whether the inode is
bad_inode in vfs_setup_quota_inode().

## Which versions are affected by CVE-2022-50782?


## How do I fix CVE-2022-50782?

Apply the vendor's patch.

## Is CVE-2022-50782 being exploited?

There is no known exploitation of CVE-2022-50782 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2022-50782 and fix it if it is affected.

What it is: CVE-2022-50782 is a denial of service vulnerability in Linux, published on 24 Dec 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2022-50782 in the wild and no public exploit code.

Affected product: Linux. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2022-50782/ (Markdown: https://insights.sbomify.com/CVE-2022-50782/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2022-50782
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2022-50782
- OSV: https://osv.dev/vulnerability/CVE-2022-50782

---
From sbomify Insights: https://insights.sbomify.com/CVE-2022-50782/
Summaries are generated and may contain mistakes; the official description above is the record.