{ "schemaVersion": 1, "attribution": [ { "source": "CISA Known Exploited Vulnerabilities", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog", "licence": "US government work" }, { "source": "GitHub Advisory Database", "url": "https://github.com/advisories", "licence": "CC BY 4.0" }, { "source": "Have I Been Pwned", "url": "https://haveibeenpwned.com/", "licence": "CC BY 4.0" }, { "source": "CVE Program (CVE records)", "url": "https://www.cve.org/Legal/TermsOfUse", "licence": "CVE Terms of Use", "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.", "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy." }, { "source": "FIRST EPSS", "url": "https://www.first.org/epss/", "licence": "free to use; FIRST requests attribution" } ], "record": { "id": "CVE-2025-71194", "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2025-71194", "idYear": 2025, "status": "PUBLISHED", "publishedAt": "2026-02-04T16:04:15.389Z", "updatedAt": "2026-10-19T18:25:23.853Z", "importedAt": "2026-10-24T01:57:44.935Z", "snapshot": { "id": "cve_2026-10-24_midnight_baseline", "at": "2026-10-24T00:00:00.000Z", "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z" }, "facts": { "title": "btrfs: fix deadlock in wait_current_trans() due to ignored transaction type", "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nbtrfs: fix deadlock in wait_current_trans() due to ignored transaction type\n\nWhen wait_current_trans() is called during start_transaction(), it\ncurrently waits for a blocked transaction without considering whether\nthe given transaction type actually needs to wait for that particular\ntransaction state. The btrfs_blocked_trans_types[] array already defines\nwhich transaction types should wait for which transaction states, but\nthis check was missing in wait_current_trans().\n\nThis can lead to a deadlock scenario involving two transactions and\npending ordered extents:\n\n 1. Transaction A is in TRANS_STATE_COMMIT_DOING state\n\n 2. A worker processing an ordered extent calls start_transaction()\n with TRANS_JOIN\n\n 3. join_transaction() returns -EBUSY because Transaction A is in\n TRANS_STATE_COMMIT_DOING\n\n 4. Transaction A moves to TRANS_STATE_UNBLOCKED and completes\n\n 5. A new Transaction B is created (TRANS_STATE_RUNNING)\n\n 6. The ordered extent from step 2 is added to Transaction B's\n pending ordered extents\n\n 7. Transaction B immediately starts commit by another task and\n enters TRANS_STATE_COMMIT_START\n\n 8. The worker finally reaches wait_current_trans(), sees Transaction B\n in TRANS_STATE_COMMIT_START (a blocked state), and waits\n unconditionally\n\n 9. However, TRANS_JOIN should NOT wait for TRANS_STATE_COMMIT_START\n according to btrfs_blocked_trans_types[]\n\n 10. Transaction B is waiting for pending ordered extents to complete\n\n 11. Deadlock: Transaction B waits for ordered extent, ordered extent\n waits for Transaction B\n\nThis can be illustrated by the following call stacks:\n CPU0 CPU1\n btrfs_finish_ordered_io()\n start_transaction(TRANS_JOIN)\n join_transaction()\n # -EBUSY (Transaction A is\n # TRANS_STATE_COMMIT_DOING)\n # Transaction A completes\n # Transaction B created\n # ordered extent added to\n # Transaction B's pending list\n btrfs_commit_transaction()\n # Transaction B enters\n # TRANS_STATE_COMMIT_START\n # waiting for pending ordered\n # extents\n wait_current_trans()\n # waits for Transaction B\n # (should not wait!)\n\nTask bstore_kv_sync in btrfs_commit_transaction waiting for ordered\nextents:\n\n __schedule+0x2e7/0x8a0\n schedule+0x64/0xe0\n btrfs_commit_transaction+0xbf7/0xda0 [btrfs]\n btrfs_sync_file+0x342/0x4d0 [btrfs]\n __x64_sys_fdatasync+0x4b/0x80\n do_syscall_64+0x33/0x40\n entry_SYSCALL_64_after_hwframe+0x44/0xa9\n\nTask kworker in wait_current_trans waiting for transaction commit:\n\n Workqueue: btrfs-syno_nocow btrfs_work_helper [btrfs]\n __schedule+0x2e7/0x8a0\n schedule+0x64/0xe0\n wait_current_trans+0xb0/0x110 [btrfs]\n start_transaction+0x346/0x5b0 [btrfs]\n btrfs_finish_ordered_io.isra.0+0x49b/0x9c0 [btrfs]\n btrfs_work_helper+0xe8/0x350 [btrfs]\n process_one_work+0x1d3/0x3c0\n worker_thread+0x4d/0x3e0\n kthread+0x12d/0x150\n ret_from_fork+0x1f/0x30\n\nFix this by passing the transaction type to wait_current_trans() and\nchecking btrfs_blocked_trans_types[cur_trans->state] against the given\ntype before deciding to wait. This ensures that transaction types which\nare allowed to join during certain blocked states will not unnecessarily\nwait and cause deadlocks.", "affected": [ { "vendor": "Linux", "product": "Linux", "defaultStatus": "unaffected", "versions": [ { "version": "4a9d8bdee368de78ace8b36da4eb2186afea162d", "status": "affected", "versionType": "git", "lessThan": "e563f59395981fcd69d130761290929806e728d6" }, { "version": "4a9d8bdee368de78ace8b36da4eb2186afea162d", "status": "affected", "versionType": "git", "lessThan": "dc84036c173cff6a432d9ab926298850b1d2a659" }, { "version": "4a9d8bdee368de78ace8b36da4eb2186afea162d", "status": "affected", "versionType": "git", "lessThan": "d7b04b40ac8e6d814e35202a0e1568809b818295" }, { "version": "4a9d8bdee368de78ace8b36da4eb2186afea162d", "status": "affected", "versionType": "git", "lessThan": "99da896614d17e8a84aeb2b2d464ac046cc8633d" }, { "version": "4a9d8bdee368de78ace8b36da4eb2186afea162d", "status": "affected", "versionType": "git", "lessThan": "8b0bb145d3bc264360f525c9717653be3522e528" }, { "version": "4a9d8bdee368de78ace8b36da4eb2186afea162d", "status": "affected", "versionType": "git", "lessThan": "9ac63333d600732a56b35ee1fa46836da671eb50" }, { "version": "4a9d8bdee368de78ace8b36da4eb2186afea162d", "status": "affected", "versionType": "git", "lessThan": "5037b342825df7094a4906d1e2a9674baab50cb2" } ] }, { "vendor": "Linux", "product": "Linux", "defaultStatus": "affected", "versions": [ { "version": "3.11", "status": "affected" }, { "version": "0", "status": "unaffected", "versionType": "semver", "lessThan": "3.11" }, { "version": "5.10.249", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.10.*" }, { "version": "5.15.199", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.15.*" }, { "version": "6.1.162", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.1.*" }, { "version": "6.6.122", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.6.*" }, { "version": "6.12.67", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.12.*" }, { "version": "6.18.7", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.18.*" }, { "version": "6.19", "status": "unaffected", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*" } ] } ] } } }