CVE-2026-23168
In the Linux kernel, the following vulnerability has been resolved: flex_proportions: make fprop_new_period() hardirq safe Bernd has reported a lockdep splat from flexible proportions code that is essentially complaining about the following race: <timer…
Does this matter?
Lower severity and a low EPSS score (0.11%). Track it; it rarely justifies an emergency change on its own.
Description
In the Linux kernel, the following vulnerability has been resolved: flex_proportions: make fprop_new_period() hardirq safe Bernd has reported a lockdep splat from flexible proportions code that is essentially complaining about the following race: <timer fires> run_timer_softirq - we are in softirq context call_timer_fn writeout_period fprop_new_period write_seqcount_begin(&p->sequence); <hardirq is raised> ... blk_mq_end_request() blk_update_request() ext4_end_bio() folio_end_writeback() __wb_writeout_add() __fprop_add_percpu_max() if (unlikely(max_frac < FPROP_FRAC_BASE)) { fprop_fraction_percpu() seq = read_seqcount_begin(&p->sequence); - sees odd sequence so loops indefinitely Note that a deadlock like this is only possible if the bdi has configured maximum fraction of writeout throughput which is very rare in general but frequent for example for FUSE bdis. To fix this problem we have to make sure write section of the sequence counter is irqsafe.
- CVSS 3.1
- 5.5 MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 0.11% probability · 2th percentile
- CISA KEV
- Not listed
- Affected
- linux/linux kernel
- Source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
References
- https://git.kernel.org/stable/c/0acc9ba7a1b5ba4d998c5753e709be904e179b75Patch
- https://git.kernel.org/stable/c/78ede9ebd679dadf480dce6f7b798e3603f88348Patch
- https://git.kernel.org/stable/c/884b2590ffcc7222cbbd6298051f4c243cc36f5dPatch
- https://git.kernel.org/stable/c/b91a84299d72ae0e05551e851e47cd3008bd025bPatch
- https://git.kernel.org/stable/c/dd9e2f5b38f1fdd49b1ab6d3a85f81c14369eaccPatch
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.