CVE-2026-89983

i2c: core: fix debugfs UAF on adapter removal

N/A
Published: September 16, 2026 at 10:32 AM UTC
Updated: October 19, 2026 at 09:18 AM UTC
1 product affected across 1 vendorLinux Kernel

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Severity
N/A
Exploit prediction
EPSS 0.2%

Description

In the Linux kernel, the following vulnerability has been resolved: i2c: core: fix debugfs UAF on adapter removal i2c_del_adapter() frees the adapter's debugfs directory before it unregisters the adapter device, but the new_device sysfs attribute stays writable until device_del(). A write racing with removal still reaches i2c_device_probe(), which passes the freed adap->debugfs to debugfs_create_dir() as the new client's parent: BUG: KASAN: slab-use-after-free in lookup_noperm_common+0x407/0x430 Read of size 4 at addr ffff88803ef87810 by task syz.0.61/6090 lookup_noperm_common+0x407/0x430 simple_start_creating+0x9c/0x110 debugfs_start_creating+0xdb/0x1a0 debugfs_create_dir+0x24/0x350 i2c_device_probe+0x814/0xbf0 It's technically possible to create a client after i2c_deregister_clients has run. That client will never be unregistered and make wait_for_completion hang. Close the window by removing the new_device attribute at the start of i2c_del_adapter(). device_remove_file() will drain any clients left.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

0e8926abfd7aee220e44be5566affd7a8580b50e4a2be5a72865bdd219b2d8c327b9fa03e87a4a9e5.15.1686.1.1136.6.556.873febd775bdbdb98c81255ff85773ac410ded5c4e2a268b0f512fb18ae5961b1fdfaf610ed6bd661
Vendor states this is fixed in 112b3d48084c820bbccf41d9783fd122e3ac4cb0 (fixed)
Vendor states this is fixed in 1f1bcd4eca6caa3e4258d9a31925112539406eb6 (fixed)
Vendor states this is fixed in 552836be2d95c688eede6371f85532abe1a71232 (fixed)
Vendor states this is fixed in 643fb872aa04342d27dbef52b2b3cf3fe71b2c7b (fixed)
Vendor states this is fixed in b15b548d52b43ba8ac4652bc2c7244a8dd1e9622 (fixed)
Vendor states this is fixed in dc33a9762538b3250ed6b5644a4d44c748be33a6 (fixed)
Vendor states this is fixed in f9094ace03e0a532cc6505d2e97b61ae738da4ed (fixed)
Vendor states this is fixed in 5.15.221 (unaffected)
Vendor states this is fixed in 6.1.188 (unaffected)
Vendor states this is fixed in 6.12.110 (unaffected)
Vendor states this is fixed in 6.18.51 (unaffected)
Vendor states this is fixed in 6.6.157 (unaffected)
Vendor states this is fixed in 6.8 (unaffected)
Vendor states this is fixed in 7.2.5 (unaffected)
Vendor states this is fixed in 7.3 (unaffected)
Vendor states this is fixed in 7.3-rc1 (unaffected)

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

Quick Info

StatusRECEIVED

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