wifi: brcmsmac: fix UAF in brcms_free_timer()

Summary

In the Linux kernel, the following vulnerability has been resolved: wifi: brcmsmac: fix UAF in brcms_free_timer() brcms_free_timer() calls brcms_del_timer() which uses the non-synchronous cancel_delayed_work() to cancel the timer's underlying delayed work. If the work callback (_brcms_timer) is already running, cancel_delayed_work() returns false without waiting, and brcms_free_timer() proceeds to kfree(t) while the callback still accesses t through container_of(). Add an explicit cancel_delayed_work_sync() after brcms_del_timer() to guarantee that any in-flight callback has completed before the timer structure is freed.

Timeline

1. Oct 6, 2026, 8:44 AM UTCCVE published
2. Oct 19, 2026, 9:15 AM UTCRecord last updated

Affected versions

• Linux Linux

  From 5b435de0d786869c95d1962121af0d7df2542009 · fixed in 10eeb0b29fd7f52487c9ae573e8d79c210a0095d; From 5b435de0d786869c95d1962121af0d7df2542009 · fixed in 74acccc928851f69184271832d690607877122af; From 5b435de0d786869c95d1962121af0d7df2542009 · fixed in 050d2486e8ed2c0a23b87249ccd23e8072721391; From 5b435de0d786869c95d1962121af0d7df2542009 · fixed in 856dabd5f2617efb23c043be9e1b22a9e6e97c41; From 5b435de0d786869c95d1962121af0d7df2542009 · fixed in 2a4841ff0b74b495cddd31ae324e922217fc2f13; From 5b435de0d786869c95d1962121af0d7df2542009 · fixed in 1edb3ddd261e973a4d577c0547e63bfa25a8170d; From 5b435de0d786869c95d1962121af0d7df2542009 · fixed in 777cb6bba59e875b16a1d8897a483a5fecfcd5d2; From 5b435de0d786869c95d1962121af0d7df2542009 · fixed in 1eeca1d5e0920fbdad6449768fd2d4364e714180

• Linux Linux

  3.2

• KernelLinux

  From 3.2.0 · fixed in 5.10.271; From 5.11.0 · fixed in 5.15.222; From 5.16.0 · fixed in 6.1.189; From 6.2.0 · fixed in 6.6.158; From 6.7.0 · fixed in 6.12.112; From 6.13.0 · fixed in 6.18.54; From 6.19.0 · fixed in 7.2.8

References 8