{"id":"CVE-2026-64232","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nblock: recompute nr_integrity_segments in blk_insert_cloned_request\n\nblk_insert_cloned_request() already recomputes nr_phys_segments\nagainst the bottom queue, because \"…","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nblock: recompute nr_integrity_segments in blk_insert_cloned_request\n\nblk_insert_cloned_request() already recomputes nr_phys_segments\nagainst the bottom queue, because \"…","severity":"critical","cvss":9.8,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","published":"2026-07-24","updated":"2026-07-27","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-64232","references":[{"url":"https://git.kernel.org/stable/c/0943f81e1b3176f27dbaf6db268fc69d8a94f0ba","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/2c6e6a18a37b905cb584eb0dda3ae482162a81ca","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/42929c98d044f126508baf54a65b0f87f932fa75","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/53a01bcc0242590eda4c452a5bd996f62457113b","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"tags":["nvd"],"epss":0.00457,"epssPercentile":0.38851,"ingestedAt":"2026-07-27T06:16:49.318Z","slug":"CVE-2026-64232","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nblock: recompute nr_integrity_segments in blk_insert_cloned_request\n\nblk_insert_cloned_request() already recomputes nr_phys_segments\nagainst the bottom queue, because \"the queue settings related to\nsegment counting may differ from the original queue.\" The exact same\nreasoning applies to integrity segments: a stacked driver's underlying\nqueue can have tighter virt_boundary_mask, seg_boundary_mask, or\nmax_segment_size than the top queue, in which case\nblk_rq_count_integrity_sg() against the bottom queue produces a\ndifferent count than the cached rq->nr_integrity_segments inherited\nfrom the source request by blk_rq_prep_clone().\n\nWhen the cached count is lower than the bottom queue's actual count,\nblk_rq_map_integrity_sg() trips\n\n\tBUG_ON(segments > rq->nr_integrity_segments);\n\non dispatch. The same families of stacked setups that motivated the\nexisting nr_phys_segments recompute -- dm-multipath fanning out to\nnvme-rdma in particular -- can produce this.\n\nMirror the nr_phys_segments handling: when the request carries\nintegrity, recompute nr_integrity_segments against the bottom queue\nand reject the request if it exceeds the bottom queue's\nmax_integrity_segments. blk_rq_count_integrity_sg() and\nqueue_max_integrity_segments() are both already available via\n<linux/blk-integrity.h>, which blk-mq.c includes.\n\nThis closes a latent gap in the stacking contract and brings the\nintegrity-segment accounting in line with the existing\nphys-segment accounting.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"midnight","depthScore":54,"depthScoreParts":{"impact":53.9,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}