{"id":"CVE-2026-89983","state":"PUBLISHED","title":"i2c: core: fix debugfs UAF on adapter removal","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ni2c: core: fix debugfs UAF on adapter removal\n\ni2c_del_adapter() frees the adapter's debugfs directory before it\nunregisters the adapter device, but the new_device sysfs attribute\nstays writable until device_del(). A write racing with removal still\nreaches i2c_device_probe(), which passes the freed adap->debugfs to\ndebugfs_create_dir() as the new client's parent:\n\n  BUG: KASAN: slab-use-after-free in lookup_noperm_common+0x407/0x430\n  Read of size 4 at addr ffff88803ef87810 by task syz.0.61/6090\n   lookup_noperm_common+0x407/0x430\n   simple_start_creating+0x9c/0x110\n   debugfs_start_creating+0xdb/0x1a0\n   debugfs_create_dir+0x24/0x350\n   i2c_device_probe+0x814/0xbf0\n\nIt's technically possible to create a client after i2c_deregister_clients\nhas run. That client will never be unregistered and make\nwait_for_completion hang.\n\nClose the window by removing the new_device attribute at the start of\ni2c_del_adapter(). device_remove_file() will drain any clients left.","publishedAt":"2026-09-16T10:32:59.461Z","updatedAt":"2026-10-19T08:55:57.766Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"0e8926abfd7aee220e44be5566affd7a8580b50e","status":"affected","lessThan":"dc33a9762538b3250ed6b5644a4d44c748be33a6","versionType":"git"},{"version":"e2a268b0f512fb18ae5961b1fdfaf610ed6bd661","status":"affected","lessThan":"1f1bcd4eca6caa3e4258d9a31925112539406eb6","versionType":"git"},{"version":"4a2be5a72865bdd219b2d8c327b9fa03e87a4a9e","status":"affected","lessThan":"f9094ace03e0a532cc6505d2e97b61ae738da4ed","versionType":"git"},{"version":"73febd775bdbdb98c81255ff85773ac410ded5c4","status":"affected","lessThan":"643fb872aa04342d27dbef52b2b3cf3fe71b2c7b","versionType":"git"},{"version":"73febd775bdbdb98c81255ff85773ac410ded5c4","status":"affected","lessThan":"112b3d48084c820bbccf41d9783fd122e3ac4cb0","versionType":"git"},{"version":"73febd775bdbdb98c81255ff85773ac410ded5c4","status":"affected","lessThan":"552836be2d95c688eede6371f85532abe1a71232","versionType":"git"},{"version":"73febd775bdbdb98c81255ff85773ac410ded5c4","status":"affected","lessThan":"b15b548d52b43ba8ac4652bc2c7244a8dd1e9622","versionType":"git"},{"version":"5.15.168","status":"affected","lessThan":"5.15.221","versionType":"semver"},{"version":"6.1.113","status":"affected","lessThan":"6.1.188","versionType":"semver"},{"version":"6.6.55","status":"affected","lessThan":"6.6.157","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/i2c/i2c-core-base.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.8","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.8","versionType":"semver"},{"version":"5.15.221","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.188","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.157","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.110","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.51","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.5","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/i2c/i2c-core-base.c"]}],"references":["https://git.kernel.org/stable/c/dc33a9762538b3250ed6b5644a4d44c748be33a6","https://git.kernel.org/stable/c/1f1bcd4eca6caa3e4258d9a31925112539406eb6","https://git.kernel.org/stable/c/f9094ace03e0a532cc6505d2e97b61ae738da4ed","https://git.kernel.org/stable/c/643fb872aa04342d27dbef52b2b3cf3fe71b2c7b","https://git.kernel.org/stable/c/112b3d48084c820bbccf41d9783fd122e3ac4cb0","https://git.kernel.org/stable/c/552836be2d95c688eede6371f85532abe1a71232","https://git.kernel.org/stable/c/b15b548d52b43ba8ac4652bc2c7244a8dd1e9622"],"weaknesses":[],"ingestedAt":"2026-10-29T20:13:26.108Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/89xxx/CVE-2026-89983.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-89983","state":"PUBLISHED","datePublished":"2026-09-16T10:32:59.461Z","dateUpdated":"2026-10-19T08:55:57.766Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-09-11T19:38:34.779Z"},"containers":{"cna":{"title":"i2c: core: fix debugfs UAF on adapter removal","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\ni2c: core: fix debugfs UAF on adapter removal\n\ni2c_del_adapter() frees the adapter's debugfs directory before it\nunregisters the adapter device, but the new_device sysfs attribute\nstays writable until device_del(). A write racing with removal still\nreaches i2c_device_probe(), which passes the freed adap->debugfs to\ndebugfs_create_dir() as the new client's parent:\n\n  BUG: KASAN: slab-use-after-free in lookup_noperm_common+0x407/0x430\n  Read of size 4 at addr ffff88803ef87810 by task syz.0.61/6090\n   lookup_noperm_common+0x407/0x430\n   simple_start_creating+0x9c/0x110\n   debugfs_start_creating+0xdb/0x1a0\n   debugfs_create_dir+0x24/0x350\n   i2c_device_probe+0x814/0xbf0\n\nIt's technically possible to create a client after i2c_deregister_clients\nhas run. That client will never be unregistered and make\nwait_for_completion hang.\n\nClose the window by removing the new_device attribute at the start of\ni2c_del_adapter(). device_remove_file() will drain any clients left."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"0e8926abfd7aee220e44be5566affd7a8580b50e","status":"affected","lessThan":"dc33a9762538b3250ed6b5644a4d44c748be33a6","versionType":"git"},{"version":"e2a268b0f512fb18ae5961b1fdfaf610ed6bd661","status":"affected","lessThan":"1f1bcd4eca6caa3e4258d9a31925112539406eb6","versionType":"git"},{"version":"4a2be5a72865bdd219b2d8c327b9fa03e87a4a9e","status":"affected","lessThan":"f9094ace03e0a532cc6505d2e97b61ae738da4ed","versionType":"git"},{"version":"73febd775bdbdb98c81255ff85773ac410ded5c4","status":"affected","lessThan":"643fb872aa04342d27dbef52b2b3cf3fe71b2c7b","versionType":"git"},{"version":"73febd775bdbdb98c81255ff85773ac410ded5c4","status":"affected","lessThan":"112b3d48084c820bbccf41d9783fd122e3ac4cb0","versionType":"git"},{"version":"73febd775bdbdb98c81255ff85773ac410ded5c4","status":"affected","lessThan":"552836be2d95c688eede6371f85532abe1a71232","versionType":"git"},{"version":"73febd775bdbdb98c81255ff85773ac410ded5c4","status":"affected","lessThan":"b15b548d52b43ba8ac4652bc2c7244a8dd1e9622","versionType":"git"},{"version":"5.15.168","status":"affected","lessThan":"5.15.221","versionType":"semver"},{"version":"6.1.113","status":"affected","lessThan":"6.1.188","versionType":"semver"},{"version":"6.6.55","status":"affected","lessThan":"6.6.157","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/i2c/i2c-core-base.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.8","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.8","versionType":"semver"},{"version":"5.15.221","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.188","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.157","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.110","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.51","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.5","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/i2c/i2c-core-base.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/dc33a9762538b3250ed6b5644a4d44c748be33a6"},{"url":"https://git.kernel.org/stable/c/1f1bcd4eca6caa3e4258d9a31925112539406eb6"},{"url":"https://git.kernel.org/stable/c/f9094ace03e0a532cc6505d2e97b61ae738da4ed"},{"url":"https://git.kernel.org/stable/c/643fb872aa04342d27dbef52b2b3cf3fe71b2c7b"},{"url":"https://git.kernel.org/stable/c/112b3d48084c820bbccf41d9783fd122e3ac4cb0"},{"url":"https://git.kernel.org/stable/c/552836be2d95c688eede6371f85532abe1a71232"},{"url":"https://git.kernel.org/stable/c/b15b548d52b43ba8ac4652bc2c7244a8dd1e9622"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-19T08:55:57.766Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15.168","versionEndExcluding":"5.15.221"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.1.113","versionEndExcluding":"6.1.188"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.6.55","versionEndExcluding":"6.6.157"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.8","versionEndExcluding":"6.12.110"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.8","versionEndExcluding":"6.18.51"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.8","versionEndExcluding":"7.2.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.8","versionEndExcluding":"7.3"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}