BlackTreeIndependent security intelligenceLinux · Linux
No CVSS base score is available from the CNA, CISA ADP or NIST. Absence of a score is not evidence of low risk; review the vendor advisory, affected exposure and exploit evidence.
Canonical’s release and source-package findings are shown separately from local repository availability.
A published vendor fix does not prove that a matching update is enabled and installable on a particular asset. Confirm the local package candidate before scheduling remediation.
| Ubuntu release | Source package | Vendor state | Fixed version | Evidence |
|---|---|---|---|---|
| Ubuntu 24.04 LTSnoble · standard archive | linux-azure-6.11 | Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition. | Not published in this feed | Canonical record ↗Source updated 10 Sept 2026 |
| Ubuntu 24.04 LTSnoble · standard archive | linux-gcp-6.11 | Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition. | Not published in this feed | Canonical record ↗Source updated 10 Sept 2026 |
| Ubuntu 24.04 LTSnoble · standard archive | linux-hwe-6.11 | Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition. | Not published in this feed | Canonical record ↗Source updated 10 Sept 2026 |
| Ubuntu 24.04 LTSnoble · standard archive | linux-lowlatency-hwe-6.11 | Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition. | Not published in this feed | Canonical record ↗Source updated 10 Sept 2026 |
| Ubuntu 24.04 LTSnoble · standard archive | linux-oem-6.11 | Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition. | Not published in this feed | Canonical record ↗Source updated 10 Sept 2026 |
| Ubuntu 24.04 LTSnoble · standard archive | linux-raspi-realtime | Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition. | Not published in this feed | Canonical record ↗Source updated 10 Sept 2026 |
| Ubuntu 24.04 LTSnoble · standard archive | linux-realtime | Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition. | Not published in this feed | Canonical record ↗Source updated 10 Sept 2026 |
| Ubuntu 24.04 LTSnoble · standard archive | linux-riscv | Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition. | Not published in this feed | Canonical record ↗Source updated 10 Sept 2026 |
No CVSS base score is available from the CNA, CISA ADP or NIST. Absence of a score is not evidence of low risk; review the vendor advisory, affected exposure and exploit evidence.
Patch availableIn the Linux kernel, the following vulnerability has been resolved: btrfs: call __btrfs_remove_free_space_cache_locked on cache load failure Now that lockdep is staying enabled through our entire CI runs I started seeing the following stack in generic/475 ------------[ cut here ]------------ WARNING: CPU: 1 PID: 2171864 at fs/btrfs/discard.c:604 btrfs_discard_update_discardable+0x98/0xb0 CPU: 1 PID: 2171864 Comm: kworker/u4:0 Not tainted 5.19.0-rc8+ #789 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-2.fc32 04/01/2014 Workqueue: btrfs-cache btrfs_work_helper RIP: 0010:btrfs_discard_update_discardable+0x98/0xb0 RSP: 0018:ffffb857c2f7bad0 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff8c85c605c200 RCX: 0000000000000001 RDX: 0000000000000000 RSI: ffffffff86807c5b RDI: ffffffff868a831e RBP: ffff8c85c4c54000 R08: 0000000000000000 R09: 0000000000000000 R10: ffff8c85c66932f0 R11: 0000000000000001 R12: ffff8c85c3899010 R13: ffff8c85d5be4f40 R14: ffff8c85c4c54000 R15: ffff8c86114bfa80 FS: 0000000000000000(0000) GS:ffff8c863bd00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f2e7f168160 CR3: 000000010289a004 CR4: 0000000000370ee0 Call Trace: __btrfs_remove_free_space_cache+0x27/0x30 load_free_space_cache+0xad2/0xaf0 caching_thread+0x40b/0x650 ? lock_release+0x137/0x2d0 btrfs_work_helper+0xf2/0x3e0 ? lock_is_held_type+0xe2/0x140 process_one_work+0x271/0x590 ? process_one_work+0x590/0x590 worker_thread+0x52/0x3b0 ? process_one_work+0x590/0x590 kthread+0xf0/0x120 ? kthread_complete_and_exit+0x20/0x20 ret_from_fork+0x1f/0x30 This is the code ctl = block_group->free_space_ctl; discard_ctl = &block_group->fs_info->discard_ctl; lockdep_assert_held(&ctl->tree_lock); We have a temporary free space ctl for loading the free space cache in order to avoid having allocations happening while we're loading the cache. When we hit an error we free it all up, however this also calls btrfs_discard_update_discardable, which requires block_group->free_space_ctl->tree_lock to be held. However this is our temporary ctl so this lock isn't held. Fix this by calling __btrfs_remove_free_space_cache_locked instead so that we only clean up the entries and do not mess with the discardable stats.
In the Linux kernel, the following vulnerability has been resolved: btrfs: call __btrfs_remove_free_space_cache_locked on cache load failure Now that lockdep is staying enabled through our entire CI runs I started seeing the following stack in generic/475 ------------[ cut here ]------------ WARNING: CPU: 1 PID: 2171864 at fs/btrfs/discard.c:604 btrfs_discard_update_discardable+0x98/0xb0 CPU: 1 PID: 2171864 Comm: kworker/u4:0 Not tainted 5.19.0-rc8+ #789 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-2.fc32 04/01/2014 Workqueue: btrfs-cache btrfs_work_helper RIP: 0010:btrfs_discard_update_discardable+0x98/0xb0 RSP: 0018:ffffb857c2f7bad0 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff8c85c605c200 RCX: 0000000000000001 RDX: 0000000000000000 RSI: ffffffff86807c5b RDI: ffffffff868a831e RBP: ffff8c85c4c54000 R08: 0000000000000000 R09: 0000000000000000 R10: ffff8c85c66932f0 R11: 0000000000000001 R12: ffff8c85c3899010 R13: ffff8c85d5be4f40 R14: ffff8c85c4c54000 R15: ffff8c86114bfa80 FS: 0000000000000000(0000) GS:ffff8c863bd00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f2e7f168160 CR3: 000000010289a004 CR4: 0000000000370ee0 Call Trace: __btrfs_remove_free_space_cache+0x27/0x30 load_free_space_cache+0xad2/0xaf0 caching_thread+0x40b/0x650 ? lock_release+0x137/0x2d0 btrfs_work_helper+0xf2/0x3e0 ? lock_is_held_type+0xe2/0x140 process_one_work+0x271/0x590 ? process_one_work+0x590/0x590 worker_thread+0x52/0x3b0 ? process_one_work+0x590/0x590 kthread+0xf0/0x120 ? kthread_complete_and_exit+0x20/0x20 ret_from_fork+0x1f/0x30 This is the code ctl = block_group->free_space_ctl; discard_ctl = &block_group->fs_info->discard_ctl; lockdep_assert_held(&ctl->tree_lock); We have a temporary free space ctl for loading the free space cache in order to avoid having allocations happening while we're loading the cache. When we hit an error we free it all up, however this also calls btrfs_discard_update_discardable, which requires block_group->free_space_ctl->tree_lock to be held. However this is our temporary ctl so this lock isn't held. Fix this by calling __btrfs_remove_free_space_cache_locked instead so that we only clean up the entries and do not mess with the discardable stats.
The current structured CVE record identifies a security weakness, but the root cause requires confirmation in the linked vendor material.
An attacker operating through the affected interface may attempt exploitation when the stated preconditions are met. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.
In the Linux kernel, the following vulnerability has been resolved: btrfs: call __btrfs_remove_free_space_cache_locked on cache load failure Now that lockdep is staying enabled through our entire CI runs I started seeing the following stack in generic/475 ------------[ cut here ]------------ WARNING: CPU: 1 PID: 2171864 at fs/btrfs/discard.c:604 btrfs_discard_update_discardable+0x98/0xb0 CPU: 1 PID: 2171864 Comm: kworker/u4:0 Not tainted 5.19.0-rc8+ #789 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-2.fc32 04/01/2014 Workqueue: btrfs-cache btrfs_work_helper RIP: 0010:btrfs_discard_update_discardable+0x98/0xb0 RSP: 0018:ffffb857c2f7bad0 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff8c85c605c200 RCX: 0000000000000001 RDX: 0000000000000000 RSI: ffffffff86807c5b RDI: ffffffff868a831e RBP: ffff8c85c4c54000 R08: 0000000000000000 R09: 0000000000000000 R10: ffff8c85c66932f0 R11: 0000000000000001 R12: ffff8c85c3899010 R13: ffff8c85d5be4f40 R14: ffff8c85c4c54000 R15: ffff8c86114bfa80 FS: 0000000000000000(0000) GS:ffff8c863bd00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f2e7f168160 CR3: 000000010289a004 CR4: 0000000000370ee0 Call Trace: __btrfs_remove_free_space_cache+0x27/0x30 load_free_space_cache+0xad2/0xaf0 caching_thread+0x40b/0x650 ? lock_release+0x137/0x2d0 btrfs_work_helper+0xf2/0x3e0 ? lock_is_held_type+0xe2/0x140 process_one_work+0x271/0x590 ? process_one_work+0x590/0x590 worker_thread+0x52/0x3b0 ? process_one_work+0x590/0x590 kthread+0xf0/0x120 ? kthread_complete_and_exit+0x20/0x20 ret_from_fork+0x1f/0x30 This is the code ctl = block_group->free_space_ctl; discard_ctl = &block_group->fs_info->discard_ctl; lockdep_assert_held(&ctl->tree_lock); We have a temporary free space ctl for loading the free space cache in order to avoid having allocations happening while we're loading the cache. When we hit an error we free it all up, however this also calls btrfs_discard_update_discardable, which requires block_group->free_space_ctl->tree_lock to be held. However this is our temporary ctl so this lock isn't held. Fix this by calling __btrfs_remove_free_space_cache_locked instead so that we only clean up the entries and do not mess with the discardable stats.
The current structured CVE record identifies a security weakness, but the root cause requires confirmation in the linked vendor material.
An attacker operating through the affected interface may attempt exploitation when the stated preconditions are met. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.
CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.
No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.
No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.
Not available from the selected scoring authority.Operational remediation based on structured source evidence.
Published 22 Oct 2025 · Last source change 11 May 2026, 19:21 UTC · CWE not yet assigned
Missing structured fields: CVSS base score, CWE classification. Missing data is not evidence of low risk; review the primary advisory.
No material field changes have been recorded since change tracking began. Routine source refreshes and cosmetic edits are intentionally excluded.