{"id":"CVE-2026-23148","title":"nvmet: fix race in nvmet_bio_done() leading to NULL pointer dereference","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nnvmet: fix race in nvmet_bio_done() leading to NULL pointer dereference\n\nThere is a race condition in nvmet_bio_done() that can cause a NULL\npointer dereference in blk_…","severity":"high","cvss":7.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","cvssSource":"cna","vendor":"Linux","product":"Linux","affected":["Linux >= 431e58d56fcb5ff1f9eb630724a922e0d2a941df < ee10b06980acca1d46e0fa36d6fb4a9578eab6e4","Linux >= 190f4c2c863af7cc5bb354b70e0805f06419c038 < 68207ceefd71cc74ce4e983fa9bd10c3122e349b","Linux >= 190f4c2c863af7cc5bb354b70e0805f06419c038 < 0fcee2cfc4b2e16e62ff8e0cc2cd8dd24efad65e","Linux 2e2028fcf924d1c6df017033c8d6e28b735a0508","Linux >= 6.12.37 < 6.12.69","Linux >= 6.15.6 < 6.16","Linux 6.16"],"ssvc":{"exploitation":"none","automatable":"yes","technicalImpact":"partial","timestamp":"2026-10-16T15:06:34.978751Z"},"published":"2026-02-14","updated":"2026-10-16","sourceUpdated":"2026-10-16T15:09:49.729Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-23148","references":[{"url":"https://git.kernel.org/stable/c/ee10b06980acca1d46e0fa36d6fb4a9578eab6e4"},{"url":"https://git.kernel.org/stable/c/68207ceefd71cc74ce4e983fa9bd10c3122e349b"},{"url":"https://git.kernel.org/stable/c/0fcee2cfc4b2e16e62ff8e0cc2cd8dd24efad65e"}],"tags":["cve.org"],"epss":0.00317,"epssPercentile":0.23033,"ingestedAt":"2026-10-16T17:24:46.639Z","slug":"CVE-2026-23148","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nnvmet: fix race in nvmet_bio_done() leading to NULL pointer dereference\n\nThere is a race condition in nvmet_bio_done() that can cause a NULL\npointer dereference in blk_cgroup_bio_start():\n\n1. nvmet_bio_done() is called when a bio completes\n2. nvmet_req_complete() is called, which invokes req->ops->queue_response(req)\n3. The queue_response callback can re-queue and re-submit the same request\n4. The re-submission reuses the same inline_bio from nvmet_req\n5. Meanwhile, nvmet_req_bio_put() (called after nvmet_req_complete)\n   invokes bio_uninit() for inline_bio, which sets bio->bi_blkg to NULL\n6. The re-submitted bio enters submit_bio_noacct_nocheck()\n7. blk_cgroup_bio_start() dereferences bio->bi_blkg, causing a crash:\n\n  BUG: kernel NULL pointer dereference, address: 0000000000000028\n  #PF: supervisor read access in kernel mode\n  RIP: 0010:blk_cgroup_bio_start+0x10/0xd0\n  Call Trace:\n   submit_bio_noacct_nocheck+0x44/0x250\n   nvmet_bdev_execute_rw+0x254/0x370 [nvmet]\n   process_one_work+0x193/0x3c0\n   worker_thread+0x281/0x3a0\n\nFix this by reordering nvmet_bio_done() to call nvmet_req_bio_put()\nBEFORE nvmet_req_complete(). This ensures the bio is cleaned up before\nthe request can be re-submitted, preventing the race condition.\n\n## Affected\n\n- `Linux >= 431e58d56fcb5ff1f9eb630724a922e0d2a941df < ee10b06980acca1d46e0fa36d6fb4a9578eab6e4`\n- `Linux >= 190f4c2c863af7cc5bb354b70e0805f06419c038 < 68207ceefd71cc74ce4e983fa9bd10c3122e349b`\n- `Linux >= 190f4c2c863af7cc5bb354b70e0805f06419c038 < 0fcee2cfc4b2e16e62ff8e0cc2cd8dd24efad65e`\n- `Linux 2e2028fcf924d1c6df017033c8d6e28b735a0508`\n- `Linux >= 6.12.37 < 6.12.69`\n- `Linux >= 6.15.6 < 6.16`\n- `Linux 6.16`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":41,"depthScoreParts":{"impact":41.3,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}