CVE-2026-93200i3c: master: Fix use-after-free of master->this

Official description

In the Linux kernel, the following vulnerability has been resolved: i3c: master: Fix use-after-free of master->this sysfs attribute callbacks for the master controller device dereference master->this. However, master->this is freed in i3c_master_detach_free_devs() before the master device itself is released. As a result, sysfs accesses can dereference a freed master->this pointer, leading to a use-after-free. Keep master->this alive until i3c_masterdev_release(), which is called after the master device and its sysfs state are being torn down. Do not free master->this as part of the normal device detach path. On the error path in i3c_master_set_info(), reset master->this and bus.cur_master to NULL before freeing the allocated device.

Affected packages & fixed versions

Affected products (as reported)

References

• https://git.kernel.org/stable/c/a9b9cae0bd887ef0d438887f20b0a417491e45f0
• https://git.kernel.org/stable/c/94af669037d129914828a851d8b2a79b4537b73f
• https://git.kernel.org/stable/c/e766605a0490723df7b61e6abd0c392889732dd7
• https://git.kernel.org/stable/c/027679d613ea73b8a00831369ec34eea804ce1bd
• https://git.kernel.org/stable/c/23a1c4288a60e253a05a882bd8928ed61beb4a48
• https://git.kernel.org/stable/c/4f3145db05fede36b35f8249b8acde5bd5d54864
• https://git.kernel.org/stable/c/50034d8d0f797c3a7a599f750a7d3e792e80dea5
• https://git.kernel.org/stable/c/feb0ed76601f3c2f91f08688c5a7d8b9d382f720