Linux Kernel up to 5.15.63/5.18.17/5.19.1 fs/btrfs/block-rsv.c btrfs_buffered_write memory corruption

Summaryinfo

A vulnerability classified as critical was found in Linux Kernel up to 5.15.63/5.18.17/5.19.1. Affected by this issue is the function btrfs_buffered_write of the file fs/btrfs/block-rsv.c. The manipulation results in memory corruption. This vulnerability is cataloged as CVE-2022-50090. There is no exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability classified as critical has been found in Linux Kernel up to 5.15.63/5.18.17/5.19.1. Affected is the function btrfs_buffered_write of the file fs/btrfs/block-rsv.c. The manipulation with an unknown input leads to a memory corruption vulnerability. CWE is classifying the issue as CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: btrfs: replace BTRFS_MAX_EXTENT_SIZE with fs_info->max_extent_size On zoned filesystem, data write out is limited by max_zone_append_size, and a large ordered extent is split according the size of a bio. OTOH, the number of extents to be written is calculated using BTRFS_MAX_EXTENT_SIZE, and that estimated number is used to reserve the metadata bytes to update and/or create the metadata items. The metadata reservation is done at e.g, btrfs_buffered_write() and then released according to the estimation changes. Thus, if the number of extent increases massively, the reserved metadata can run out. The increase of the number of extents easily occurs on zoned filesystem if BTRFS_MAX_EXTENT_SIZE > max_zone_append_size. And, it causes the following warning on a small RAM environment with disabling metadata over-commit (in the following patch). [75721.498492] ------------[ cut here ]------------ [75721.505624] BTRFS: block rsv 1 returned -28 [75721.512230] WARNING: CPU: 24 PID: 2327559 at fs/btrfs/block-rsv.c:537 btrfs_use_block_rsv+0x560/0x760 [btrfs] [75721.581854] CPU: 24 PID: 2327559 Comm: kworker/u64:10 Kdump: loaded Tainted: G W 5.18.0-rc2-BTRFS-ZNS+ #109 [75721.597200] Hardware name: Supermicro Super Server/H12SSL-NT, BIOS 2.0 02/22/2021 [75721.607310] Workqueue: btrfs-endio-write btrfs_work_helper [btrfs] [75721.616209] RIP: 0010:btrfs_use_block_rsv+0x560/0x760 [btrfs] [75721.646649] RSP: 0018:ffffc9000fbdf3e0 EFLAGS: 00010286 [75721.654126] RAX: 0000000000000000 RBX: 0000000000004000 RCX: 0000000000000000 [75721.663524] RDX: 0000000000000004 RSI: 0000000000000008 RDI: fffff52001f7be6e [75721.672921] RBP: ffffc9000fbdf420 R08: 0000000000000001 R09: ffff889f8d1fc6c7 [75721.682493] R10: ffffed13f1a3f8d8 R11: 0000000000000001 R12: ffff88980a3c0e28 [75721.692284] R13: ffff889b66590000 R14: ffff88980a3c0e40 R15: ffff88980a3c0e8a [75721.701878] FS: 0000000000000000(0000) GS:ffff889f8d000000(0000) knlGS:0000000000000000 [75721.712601] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [75721.720726] CR2: 000055d12e05c018 CR3: 0000800193594000 CR4: 0000000000350ee0 [75721.730499] Call Trace: [75721.735166] <TASK> [75721.739886] btrfs_alloc_tree_block+0x1e1/0x1100 [btrfs] [75721.747545] ? btrfs_alloc_logged_file_extent+0x550/0x550 [btrfs] [75721.756145] ? btrfs_get_32+0xea/0x2d0 [btrfs] [75721.762852] ? btrfs_get_32+0xea/0x2d0 [btrfs] [75721.769520] ? push_leaf_left+0x420/0x620 [btrfs] [75721.776431] ? memcpy+0x4e/0x60 [75721.781931] split_leaf+0x433/0x12d0 [btrfs] [75721.788392] ? btrfs_get_token_32+0x580/0x580 [btrfs] [75721.795636] ? push_for_double_split.isra.0+0x420/0x420 [btrfs] [75721.803759] ? leaf_space_used+0x15d/0x1a0 [btrfs] [75721.811156] btrfs_search_slot+0x1bc3/0x2790 [btrfs] [75721.818300] ? lock_downgrade+0x7c0/0x7c0 [75721.824411] ? free_extent_buffer.part.0+0x107/0x200 [btrfs] [75721.832456] ? split_leaf+0x12d0/0x12d0 [btrfs] [75721.839149] ? free_extent_buffer.part.0+0x14f/0x200 [btrfs] [75721.846945] ? free_extent_buffer+0x13/0x20 [btrfs] [75721.853960] ? btrfs_release_path+0x4b/0x190 [btrfs] [75721.861429] btrfs_csum_file_blocks+0x85c/0x1500 [btrfs] [75721.869313] ? rcu_read_lock_sched_held+0x16/0x80 [75721.876085] ? lock_release+0x552/0xf80 [75721.881957] ? btrfs_del_csums+0x8c0/0x8c0 [btrfs] [75721.888886] ? __kasan_check_write+0x14/0x20 [75721.895152] ? do_raw_read_unlock+0x44/0x80 [75721.901323] ? _raw_write_lock_irq+0x60/0x80 [75721.907983] ? btrfs_global_root+0xb9/0xe0 [btrfs] [75721.915166] ? btrfs_csum_root+0x12b/0x180 [btrfs] [75721.921918] ? btrfs_get_global_root+0x820/0x820 [btrfs] [75721.929166] ? _raw_write_unlock+0x23/0x40 [75721.935116] ? unpin_extent_cache+0x1e3/0x390 [btrfs] [75721.942041] btrfs_finish_ordered_io.isra.0+0xa0c/0x1dc0 [btrfs] [75721.949906] ? try_to_wake_up+0x30/0x14a0 [75721.955700] ? btrfs_unlink_subvol+0xda0/0xda0 [btrfs] [75721.962661] ? rcu ---truncated---

The advisory is shared for download at git.kernel.org. This vulnerability is traded as CVE-2022-50090 since 06/18/2025. The exploitability is told to be easy. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 11/30/2025).

The vulnerability scanner Nessus provides a plugin with the ID 250199 (Linux Distros Unpatched Vulnerability : CVE-2022-50090), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.15.64, 5.18.18 or 5.19.2 eliminates this vulnerability. Applying the patch 1aa262c1d056551dd1246115af8b7e351184deae/6cb4b96df97082a54634ba02196516919cda228c/096e8eb9639b342bc35f9b741cf05e26d0106e92/f7b12a62f008a3041f42f2426983e59a6a0a3c59 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (250199) and CERT Bund (WID-SEC-2025-1350). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Affected

• Debian Linux
• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• SUSE openSUSE
• Open Source Linux Kernel
• RESF Rocky Linux
• Dell Avamar
• Dell NetWorker
• Dell Secure Connect Gateway
• IBM QRadar SIEM

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 5.15.0
• 5.15.1
• 5.15.2
• 5.15.3
• 5.15.4
• 5.15.5
• 5.15.6
• 5.15.7
• 5.15.8
• 5.15.9
• 5.15.10
• 5.15.11
• 5.15.12
• 5.15.13
• 5.15.14
• 5.15.15
• 5.15.16
• 5.15.17
• 5.15.18
• 5.15.19
• 5.15.20
• 5.15.21
• 5.15.22
• 5.15.23
• 5.15.24
• 5.15.25
• 5.15.26
• 5.15.27
• 5.15.28
• 5.15.29
• 5.15.30
• 5.15.31
• 5.15.32
• 5.15.33
• 5.15.34
• 5.15.35
• 5.15.36
• 5.15.37
• 5.15.38
• 5.15.39
• 5.15.40
• 5.15.41
• 5.15.42
• 5.15.43
• 5.15.44
• 5.15.45
• 5.15.46
• 5.15.47
• 5.15.48
• 5.15.49
• 5.15.50
• 5.15.51
• 5.15.52
• 5.15.53
• 5.15.54
• 5.15.55
• 5.15.56
• 5.15.57
• 5.15.58
• 5.15.59
• 5.15.60
• 5.15.61
• 5.15.62
• 5.15.63
• 5.18.0
• 5.18.1
• 5.18.2
• 5.18.3
• 5.18.4
• 5.18.5
• 5.18.6
• 5.18.7
• 5.18.8
• 5.18.9
• 5.18.10
• 5.18.11
• 5.18.12
• 5.18.13
• 5.18.14
• 5.18.15
• 5.18.16
• 5.18.17
• 5.19.0
• 5.19.1

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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Entryinfo

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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