Answer in brief
CVE-2026-89655 records a Unknown severity vulnerability in ceph: fix UAF in __kick_flushing_caps() on cf entry freed during unlock. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <2701431aa3cc8b23efe6890182e7b04f5e76fab5 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <fe46746087b5b9c5bb2d022df6c7819218494ced || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <2dba24dcd5050be4b7b119e6f0b01f62203b5d26 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <7af4c4f01305b0935adf6d4301b1ec407025485d || >=0 <6.12.109 || >=0 <6.18.50 || >=0 <7.2.4 | 2701431aa3cc8b23efe6890182e7b04f5e76fab5, fe46746087b5b9c5bb2d022df6c7819218494ced, 2dba24dcd5050be4b7b119e6f0b01f62203b5d26, 7af4c4f01305b0935adf6d4301b1ec407025485d, 6.12.109, 6.18.50, 7.2.4 |
Published upstream
Sep 11, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Sep 11, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Sep 11, 2026
In the Linux kernel, the following vulnerability has been resolved: ceph: fix UAF in __kick_flushing_caps() on cf entry freed during unlock list_for_each_entry() iterates ci->i_cap_flush_list but drops i_ceph_lock to send cap messages. During the unlock window, handle_cap_flush_ack() can acquire i_ceph_lock, detach cf entries with tid <= flush_tid from the list, release i_ceph_lock, and free them via ceph_free_cap_flush() outside any lock. When the original thread reacquires i_ceph_lock and the for-loop macro advances via cf = list_next_entry(cf, i_list), it dereferences cf->i_list.next on freed memory. The race timeline: __kick_flushing_caps() handle_cap_flush_ack() ----------------------- ----------------------- holds i_ceph_lock <--- iterates to cf (tid=10) prepares FLUSH message drops i_ceph_lock <--- __send_cap() ── FLUSH(tid=10) MDS sends FLUSH_ACK(tid=10) ---> acquires i_ceph_lock cf->tid(10) <= flush_tid(10), detaches cf from i_cap_flush_list drops i_ceph_lock ceph_free_cap_flush(cf) <- frees it! acquires i_ceph_lock <--- for-loop advances: cf = list_next_entry(cf, i_list) -- UAF on freed cf->i_list.next The cf was just sent by __kick_flushing_caps itself via __send_cap(). The MDS may respond with FLUSH_ACK quickly enough that handle_cap_flush_ack() frees cf before __kick_flushing_caps can finish the iteration. Fix by converting to a manual while loop: save the next pointer under i_ceph_lock before dropping it, then use the saved pointer after reacquiring, so the potentially-freed cf is never accessed again.
Quoted source text, attributed separately from HOL analysis.