CVE-2026-68214media: rtl2832: fix use-after-free in rtl2832_remove()

Official description

In the Linux kernel, the following vulnerability has been resolved: media: rtl2832: fix use-after-free in rtl2832_remove() cancel_delayed_work_sync() is called before i2c_mux_del_adapters() in rtl2832_remove(). While the cancel waits for any running instance of i2c_gate_work to finish, it does not prevent the timer from being rescheduled by a concurrent thread. During probe, the r820t_attach() call attempts I2C transfers through the mux adapter. These transfers go through i2c_mux_master_xfer(), which calls rtl2832_deselect() after the transfer completes, rescheduling i2c_gate_work via schedule_delayed_work(). If this transfer is still in flight when rtl2832_remove() runs, rtl2832_deselect() can reschedule i2c_gate_work after it has been cancelled, causing a use-after-free when kfree(dev) is called. Fix this by calling i2c_mux_del_adapters() before cancel_delayed_work_sync(). Once the mux adapter is unregistered, no new I2C transfers can go through it, so rtl2832_deselect() can no longer reschedule i2c_gate_work. The subsequent cancel_delayed_work_sync() is then guaranteed to be final.

Affected packages & fixed versions

Affected products (as reported)

References

• https://git.kernel.org/stable/c/1e8a6bc19403661661fed5ae82f6eca6c9cdfad2
• https://git.kernel.org/stable/c/68a9c0290897c1436ddceb8cea604c93377a0299
• https://git.kernel.org/stable/c/13c06056699e66ff7109ba68658cc6ea4a23f516
• https://git.kernel.org/stable/c/9acd5bbbe1df8e487e49488692c224496d4c9e16
• https://git.kernel.org/stable/c/24bef237eef8dd1ebcffb129ba21891ddad0d309
• https://git.kernel.org/stable/c/2c71bda6edc630a1f8c3c45d8df5fc22d234e042
• https://git.kernel.org/stable/c/90d781711418881f8c836c2a859cc2886625d750
• https://git.kernel.org/stable/c/680daf40a82d483949f87f0d8f98639dc47e610c