{"id":"CVE-2026-90209","title":"In the Linux kernel, the following vulnerability has been resolved:\n\ns390/debug: Fix deadlock during unregister\n\nUnregistering an s390dbf debug area while one of the associated debugfs\nfiles is being written to can cause a deadlock:\n\n$ e…","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\ns390/debug: Fix deadlock during unregister\n\nUnregistering an s390dbf debug area while one of the associated debugfs\nfiles is being written to can cause a deadlock:\n\n$ e…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= 9372a82892c2caa6bccab9a4081166fa769699f8 < a214c3dacc779b2afcb0ac9c8001e45ee4ffb2ed","Linux >= 9372a82892c2caa6bccab9a4081166fa769699f8 < 183f8f6d64bb0510070c856b9927618c53014a7b","Linux >= 9372a82892c2caa6bccab9a4081166fa769699f8 < a08b70ed2d1ec907353a72f15163b8e34ff4b2f8","Linux >= 9372a82892c2caa6bccab9a4081166fa769699f8 < 45bb341d1b73eb293e0dd43d9b72bbc8b615d0ba","Linux >= 9372a82892c2caa6bccab9a4081166fa769699f8 < 5d83f3faa3fb7f23f298cfd40382611999de5d1d","Linux >= 9372a82892c2caa6bccab9a4081166fa769699f8 < 54e1259b75d6402a1d0cfb822b9bb2c507e53dab","Linux >= 9372a82892c2caa6bccab9a4081166fa769699f8 < 445c31ac638fd1af203d79bdf25fc0cb3149fbbc","Linux c68ba4a708fbd0efdc384cd29250bb292a45e559","Linux 86f9980909f31ab205323eeeb290fe3cbb4952b4","Linux fe5793e90d3f572a87ba67fe2f0e1679fdff14f8","Linux e234f66168f0d50c0d28154fb983a14e85c3c526","Linux >= 5.4.146 < 5.5","Linux >= 5.10.65 < 5.11","Linux >= 5.13.17 < 5.14","Linux >= 5.14.4 < 5.15","Linux 5.15"],"published":"2026-09-17","updated":"2026-09-17","sourceUpdated":"2026-09-17T17:17:16.060","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-90209","references":[{"url":"https://git.kernel.org/stable/c/183f8f6d64bb0510070c856b9927618c53014a7b","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/445c31ac638fd1af203d79bdf25fc0cb3149fbbc","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/45bb341d1b73eb293e0dd43d9b72bbc8b615d0ba","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/54e1259b75d6402a1d0cfb822b9bb2c507e53dab","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/5d83f3faa3fb7f23f298cfd40382611999de5d1d","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/a08b70ed2d1ec907353a72f15163b8e34ff4b2f8","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/a214c3dacc779b2afcb0ac9c8001e45ee4ffb2ed","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"tags":["nvd","cve.org"],"ingestedAt":"2026-09-17T16:21:47.858Z","epss":0.00206,"epssPercentile":0.1094,"slug":"CVE-2026-90209","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\ns390/debug: Fix deadlock during unregister\n\nUnregistering an s390dbf debug area while one of the associated debugfs\nfiles is being written to can cause a deadlock:\n\n$ echo >.../vmur/level    $ rmmod vmur\n===================================================\ndebugfs write\ndebugfs_file_get()\n                          debug_unregister()\n                          mutex_lock(debug_mutex)\n                          debugfs_remove()\n                          wait for debugfs_file_put()\ndebug_file_ops.write()\ndebug_input()\nmutex_lock(debug_mutex) ==> DEADLOCK\n\nFix this by splitting debug_unregister() into an s390dbf and debugfs\npart, and running only the s390dbf part with debug_mutex locked.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}