Upstream information
Description
In the Linux kernel, the following vulnerability has been resolved:btrfs: reject free space cache with more entries than pages
When loading a v1 free space cache, __load_free_space_cache() takes
num_entries and num_bitmaps straight from the on-disk
btrfs_free_space_header. That header is stored in the tree_root under a key
with type 0, which the tree-checker has no case for, so neither count is
validated before the load trusts it.
The load loops num_entries times and maps the next page whenever the current
one runs out, going through io_ctl_check_crc() -> io_ctl_map_page(), which
does io_ctl->pages[io_ctl->index++]. But pages[] is allocated in
io_ctl_init() from the cache inode's i_size, not from num_entries:
num_pages = DIV_ROUND_UP(i_size_read(inode), PAGE_SIZE);
io_ctl->pages = kcalloc(num_pages, sizeof(struct page *), GFP_NOFS);
So if num_entries claims more records than the pages can hold, io_ctl->index
runs off the end of pages[]. The write side never hits this because
io_ctl_add_entry() and io_ctl_add_bitmap() both stop once
io_ctl->index >= io_ctl->num_pages; the read side just never had the same
check.
To trigger it, take a clean cache (num_entries = <N> here), set num_entries
in the header to 0x10000, and fix up the leaf checksum so it still passes
the tree-checker. The cache inode has i_size = 65536, so num_pages is 16 and
pages[] is a 16-pointer (kmalloc-128) array. The load now tries to read
65536 entries, io_ctl->index walks up to 16, and pages[16] is read past the
array:
BUG: KASAN: slab-out-of-bounds in io_ctl_check_crc (fs/btrfs/free-space-cache.c:420 fs/btrfs/free-space-cache.c:565)
Read of size 8 at addr ffff88800c833a80 by task kworker/u8:3/58
io_ctl_check_crc (fs/btrfs/free-space-cache.c:420 fs/btrfs/free-space-cache.c:565)
__load_free_space_cache (fs/btrfs/free-space-cache.c:655 fs/btrfs/free-space-cache.c:820)
load_free_space_cache (fs/btrfs/free-space-cache.c:1017)
caching_thread (fs/btrfs/block-group.c:880)
btrfs_work_helper (fs/btrfs/async-thread.c:312)
process_one_work
worker_thread
kthread
ret_from_fork
free-space-cache.c:420 is io_ctl_map_page(), inlined into io_ctl_check_crc()
at line 565, which is why that is the frame KASAN names. The out-of-bounds
slot is then treated as a struct page and handed to crc32c(), so the bad
read turns into a GP fault.
Add the missing check to io_ctl_check_crc(), which is where both the entry
loop and the bitmap loop end up. When num_entries is too large the load now
fails like any corrupt cache: __load_free_space_cache() drops it and rebuilds
the free space from the extent tree, so a valid cache is never rejected.
SUSE information
Overall state of this security issue: Pending
This issue is currently rated as having moderate severity.
| CVSS detail | SUSE |
|---|---|
| Base Score | 5.5 |
| Vector | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
| Attack Vector | Local |
| Attack Complexity | Low |
| Privileges Required | Low |
| User Interaction | None |
| Scope | Unchanged |
| Confidentiality Impact | None |
| Integrity Impact | None |
| Availability Impact | High |
| CVSSv3 Version | 3.1 |
| CVSS detail | SUSE |
|---|---|
| Base Score | 6.8 |
| Vector | CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N |
| Attack Vector | Local |
| Attack Complexity | Low |
| Attack Requirements | None |
| Privileges Required | Low |
| User Interaction | None |
| Vulnerable System Confidentiality Impact | None |
| Vulnerable System Integrity Impact | None |
| Vulnerable System Availability Impact | High |
| Subsequent System Confidentiality Impact | None |
| Subsequent System Integrity Impact | None |
| Subsequent System Availability Impact | None |
| CVSSv4 Version | 4.0 |
Note from the SUSE Security Team on the kernel-default package
SUSE will no longer fix all CVEs in the Linux Kernel anymore, but declare some bug classes as won't fix. Please refer to TID 21496 for more details. SUSE Bugzilla entry: 1274006 [NEW] No SUSE Security Announcements cross referenced.Status of this issue by product and package
Please note that this evaluation state might be work in progress, incomplete or outdated. Also information for service packs in the LTSS phase is only included for issues meeting the LTSS criteria. If in doubt, feel free to contact us for clarification. The updates are grouped by state of their lifecycle. SUSE product lifecycles are documented on the lifecycle page.
| Product(s) | Source package | State |
|---|---|---|
| Products under general support and receiving all security fixes. | ||
| SUSE Linux Enterprise Desktop 15 SP7 | kernel-default | Affected |
| SUSE Linux Enterprise Desktop 15 SP7 | kernel-source | Affected |
| SUSE Linux Enterprise High Availability Extension 15 SP7 | kernel-default | Affected |
| SUSE Linux Enterprise High Availability Extension 15 SP7 | kernel-source | Affected |
| SUSE Linux Enterprise High Availability Extension 16.0 | kernel-default | Affected |
| SUSE Linux Enterprise High Availability Extension 16.0 | kernel-source | Affected |
| SUSE Linux Enterprise High Availability Extension 16.1 | kernel-default | Affected |
| SUSE Linux Enterprise High Availability Extension 16.1 | kernel-source | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP7 | kernel-default | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP7 | kernel-source | Affected |
| SUSE Linux Enterprise Live Patching 15 SP7 | kernel-default | Affected |
| SUSE Linux Enterprise Live Patching 15 SP7 | kernel-source | Affected |
| SUSE Linux Enterprise Micro 5.3 | kernel-default | Affected |
| SUSE Linux Enterprise Micro 5.3 | kernel-rt | Affected |
| SUSE Linux Enterprise Micro 5.3 | kernel-source | Affected |
| SUSE Linux Enterprise Micro 5.3 | kernel-source-rt | Affected |
| SUSE Linux Enterprise Micro 5.4 | kernel-default | Affected |
| SUSE Linux Enterprise Micro 5.4 | kernel-rt | Affected |
| SUSE Linux Enterprise Micro 5.4 | kernel-source | Affected |
| SUSE Linux Enterprise Micro 5.4 | kernel-source-rt | Affected |
| SUSE Linux Enterprise Micro 5.5 | kernel-default | Affected |
| SUSE Linux Enterprise Micro 5.5 | kernel-source | Affected |
| SUSE Linux Enterprise Micro 5.5 | kernel-source-rt | Affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP7 | kernel-default | Affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP7 | kernel-source | Affected |
| SUSE Linux Enterprise Module for Development Tools 15 SP7 | kernel-default | Affected |
| SUSE Linux Enterprise Module for Development Tools 15 SP7 | kernel-source | Affected |
| SUSE Linux Enterprise Module for Legacy 15 SP7 | kernel-default | Affected |
| SUSE Linux Enterprise Module for Legacy 15 SP7 | kernel-source | Affected |
| SUSE Linux Enterprise Real Time 15 SP7 | kernel-source-rt | Affected |
| SUSE Linux Enterprise Server 15 SP7 | kernel-default | Affected |
| SUSE Linux Enterprise Server 15 SP7 | kernel-source | Affected |
| SUSE Linux Enterprise Server 16.0 | kernel-default | Affected |
| SUSE Linux Enterprise Server 16.0 | kernel-source | Affected |
| SUSE Linux Enterprise Server 16.1 | kernel-default | Affected |
| SUSE Linux Enterprise Server 16.1 | kernel-source | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP7 | kernel-default | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP7 | kernel-source | Affected |
| SUSE Linux Enterprise Server for SAP applications 16.0 | kernel-default | Affected |
| SUSE Linux Enterprise Server for SAP applications 16.0 | kernel-source | Affected |
| SUSE Linux Enterprise Server for SAP applications 16.1 | kernel-default | Affected |
| SUSE Linux Enterprise Server for SAP applications 16.1 | kernel-source | Affected |
| SUSE Linux Enterprise Workstation Extension 15 SP7 | kernel-default | Affected |
| SUSE Linux Enterprise Workstation Extension 15 SP7 | kernel-source | Affected |
| SUSE Linux Micro 6.0 | kernel-default | Affected |
| SUSE Linux Micro 6.0 | kernel-source | Affected |
| SUSE Linux Micro 6.0 | kernel-source-rt | Affected |
| SUSE Linux Micro 6.1 | kernel-default | Affected |
| SUSE Linux Micro 6.1 | kernel-source | Affected |
| SUSE Linux Micro 6.1 | kernel-source-rt | Affected |
| SUSE Linux Micro 6.2 | kernel-default | Affected |
| SUSE Linux Micro 6.2 | kernel-source | Affected |
| SUSE Linux Micro Extras 6.0 | kernel-default | Affected |
| SUSE Linux Micro Extras 6.0 | kernel-source | Affected |
| SUSE Linux Micro Extras 6.0 | kernel-source-rt | Affected |
| SUSE Linux Micro Extras 6.1 | kernel-default | Affected |
| SUSE Linux Micro Extras 6.1 | kernel-source | Affected |
| SUSE Real Time Module 15 SP7 | kernel-source-rt | Affected |
| openSUSE Leap 16.0 | kernel-source | Affected |
| Products under Long Term Service Pack support and receiving important and critical security fixes. | ||
| SUSE Linux Enterprise High Performance Computing 12 SP5 | kernel-default | Affected |
| SUSE Linux Enterprise High Performance Computing 12 SP5 | kernel-source | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP4 | kernel-source | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS | kernel-default | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS | kernel-source | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5 | kernel-source | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS | kernel-default | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS | kernel-source | Affected |
| SUSE Linux Enterprise Live Patching 12 SP5 | kernel-default | Affected |
| SUSE Linux Enterprise Live Patching 12 SP5 | kernel-source | Affected |
| SUSE Linux Enterprise Live Patching 15 SP4 | kernel-default | Affected |
| SUSE Linux Enterprise Live Patching 15 SP4 | kernel-source | Affected |
| SUSE Linux Enterprise Live Patching 15 SP5 | kernel-default | Affected |
| SUSE Linux Enterprise Live Patching 15 SP5 | kernel-source | Affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP4 | kernel-source | Affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP5 | kernel-source | Affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP6 | kernel-source | Affected |
| SUSE Linux Enterprise Module for Development Tools 15 SP4 | kernel-source | Affected |
| SUSE Linux Enterprise Module for Development Tools 15 SP5 | kernel-source | Affected |
| SUSE Linux Enterprise Module for Development Tools 15 SP6 | kernel-source | Affected |
| SUSE Linux Enterprise Server 11 SP4 LTSS EXTREME CORE | kernel-default | Affected |
| SUSE Linux Enterprise Server 11 SP4 LTSS EXTREME CORE | kernel-source | Affected |
| SUSE Linux Enterprise Server 12 SP5 | kernel-source | Affected |
| SUSE Linux Enterprise Server 12 SP5-LTSS | kernel-default | Affected |
| SUSE Linux Enterprise Server 12 SP5-LTSS | kernel-source | Affected |
| SUSE Linux Enterprise Server 12 SP5-LTSS Extended Security | kernel-default | Affected |
| SUSE Linux Enterprise Server 12 SP5-LTSS Extended Security | kernel-source | Affected |
| SUSE Linux Enterprise Server 15 SP4 | kernel-source | Affected |
| SUSE Linux Enterprise Server 15 SP4-LTSS | kernel-default | Affected |
| SUSE Linux Enterprise Server 15 SP4-LTSS | kernel-source | Affected |
| SUSE Linux Enterprise Server 15 SP5 | kernel-source | Affected |
| SUSE Linux Enterprise Server 15 SP5-LTSS | kernel-default | Affected |
| SUSE Linux Enterprise Server 15 SP5-LTSS | kernel-source | Affected |
| SUSE Linux Enterprise Server 15 SP6 | kernel-source | Affected |
| SUSE Linux Enterprise Server 15 SP6-LTSS | kernel-default | Affected |
| SUSE Linux Enterprise Server 15 SP6-LTSS | kernel-source | Affected |
| SUSE Linux Enterprise Server LTSS Extended Security 12 SP5 | kernel-source | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP6 | kernel-default | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP6 | kernel-source | Affected |
| SUSE Manager Proxy 4.3 | kernel-source | Affected |
| SUSE Manager Proxy LTS 4.3 | kernel-source | Affected |
| SUSE Manager Retail Branch Server 4.3 | kernel-source | Affected |
| SUSE Manager Retail Branch Server LTS 4.3 | kernel-source | Affected |
| SUSE Manager Server 4.3 | kernel-source | Affected |
| SUSE Manager Server LTS 4.3 | kernel-source | Affected |
| Products past their end of life and not receiving proactive updates anymore. | ||
| SUSE CaaS Platform 4.0 | kernel-source | Affected |
| SUSE Enterprise Storage 6 | kernel-source | Affected |
| SUSE Enterprise Storage 7 | kernel-source | Affected |
| SUSE Enterprise Storage 7.1 | kernel-source | Affected |
| SUSE Linux Enterprise Desktop 11 SP4 | kernel-source | Affected |
| SUSE Linux Enterprise Desktop 15 SP1 | kernel-source | Affected |
| SUSE Linux Enterprise Desktop 15 SP2 | kernel-source | Affected |
| SUSE Linux Enterprise Desktop 15 SP3 | kernel-source | Affected |
| SUSE Linux Enterprise Desktop 15 SP4 | kernel-source | Affected |
| SUSE Linux Enterprise Desktop 15 SP5 | kernel-source | Affected |
| SUSE Linux Enterprise Desktop 15 SP6 | kernel-source | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP1 | kernel-source | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP1-ESPOS | kernel-source | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP1-LTSS | kernel-source | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP2 | kernel-source | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP2-ESPOS | kernel-source | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP2-LTSS | kernel-source | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP3 | kernel-source | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP3-ESPOS | kernel-source | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP3-LTSS | kernel-source | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS | kernel-source | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS | kernel-source | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP6 | kernel-source | Affected |
| SUSE Linux Enterprise Micro 5.0 | kernel-default | Affected |
| SUSE Linux Enterprise Micro 5.1 | kernel-default | Affected |
| SUSE Linux Enterprise Micro 5.2 | kernel-default | Affected |
| SUSE Linux Enterprise Micro 5.2 | kernel-source | Affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP1 | kernel-source | Affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP2 | kernel-source | Affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP3 | kernel-source | Affected |
| SUSE Linux Enterprise Module for Development Tools 15 SP1 | kernel-source | Affected |
| SUSE Linux Enterprise Module for Development Tools 15 SP2 | kernel-source | Affected |
| SUSE Linux Enterprise Module for Development Tools 15 SP3 | kernel-source | Affected |
| SUSE Linux Enterprise Real Time 15 SP2 | kernel-source | Affected |
| SUSE Linux Enterprise Real Time 15 SP3 | kernel-source | Affected |
| SUSE Linux Enterprise Real Time 15 SP4 | kernel-source | Affected |
| SUSE Linux Enterprise Real Time 15 SP4 | kernel-source-rt | Affected |
| SUSE Linux Enterprise Real Time 15 SP5 | kernel-source-rt | Affected |
| SUSE Linux Enterprise Server 11 SP4 | kernel-source | Affected |
| SUSE Linux Enterprise Server 11 SP4-LTSS | kernel-source | Affected |
| SUSE Linux Enterprise Server 15 SP1 | kernel-source | Affected |
| SUSE Linux Enterprise Server 15 SP1-BCL | kernel-source | Affected |
| SUSE Linux Enterprise Server 15 SP1-LTSS | kernel-default | Affected |
| SUSE Linux Enterprise Server 15 SP1-LTSS | kernel-source | Affected |
| SUSE Linux Enterprise Server 15 SP2 | kernel-source | Affected |
| SUSE Linux Enterprise Server 15 SP2-BCL | kernel-source | Affected |
| SUSE Linux Enterprise Server 15 SP2-LTSS | kernel-default | Affected |
| SUSE Linux Enterprise Server 15 SP2-LTSS | kernel-source | Affected |
| SUSE Linux Enterprise Server 15 SP3 | kernel-source | Affected |
| SUSE Linux Enterprise Server 15 SP3-BCL | kernel-source | Affected |
| SUSE Linux Enterprise Server 15 SP3-LTSS | kernel-default | Affected |
| SUSE Linux Enterprise Server 15 SP3-LTSS | kernel-source | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP1 | kernel-source | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP2 | kernel-source | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP3 | kernel-source | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP4 | kernel-default | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP4 | kernel-source | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP5 | kernel-default | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP5 | kernel-source | Affected |
| SUSE Manager Proxy 4.0 | kernel-source | Affected |
| SUSE Manager Proxy 4.1 | kernel-source | Affected |
| SUSE Manager Proxy 4.2 | kernel-source | Affected |
| SUSE Manager Retail Branch Server 4.0 | kernel-source | Affected |
| SUSE Manager Retail Branch Server 4.1 | kernel-source | Affected |
| SUSE Manager Retail Branch Server 4.2 | kernel-source | Affected |
| SUSE Manager Server 4.0 | kernel-source | Affected |
| SUSE Manager Server 4.1 | kernel-source | Affected |
| SUSE Manager Server 4.2 | kernel-source | Affected |
| SUSE Real Time Module 15 SP4 | kernel-source-rt | Affected |
| SUSE Real Time Module 15 SP5 | kernel-source-rt | Affected |
| openSUSE Leap 15.3 | kernel-source | Affected |
| openSUSE Leap 15.4 | kernel-source | Affected |
| openSUSE Leap 15.4 | kernel-source-rt | Affected |
| openSUSE Leap 15.5 | kernel-source | Affected |
| openSUSE Leap 15.5 | kernel-source-rt | Affected |
| openSUSE Leap 15.6 | kernel-source | Affected |
SUSE Timeline for this CVE
CVE page created: Wed Aug 5 17:46:56 2026CVE page last modified: Thu Aug 6 13:39:57 2026