CVE-2026-89900media: cec: core: Fix kmemleak due to missed rc_free_device() call

Official description

In the Linux kernel, the following vulnerability has been resolved: media: cec: core: Fix kmemleak due to missed rc_free_device() call The commit dccc0c3ddf8f ("media: rc: fix race between unregister and urb/irq callbacks") removed the implicit call to rc_free_device() from rc_unregister_device(). However, the commit missed to remove the NULL assignment of adap->rc that is now causing rc_free_device() to never be called on an allocated rc device. kmemleak reports following after e.g. dw-hdmi unbind: unreferenced object 0xffff00010ac10000 (size 4096): comm "kworker/u16:1", pid 39, jiffies 4294897739 hex dump (first 32 bytes): 20 23 4b 0a 01 00 ff ff 08 00 c1 0a 01 00 ff ff #K............. 08 00 c1 0a 01 00 ff ff 00 00 00 00 00 00 00 00 ................ backtrace (crc e11baccc): kmemleak_alloc+0x38/0x44 __kmalloc_cache_noprof+0x4a8/0x5e0 rc_allocate_device+0x48/0x2a0 cec_allocate_adapter+0x3ac/0x800 dw_hdmi_cec_probe+0x264/0x634 platform_probe+0xc0/0x188 really_probe+0x4a4/0x8e0 __driver_probe_device+0x2f8/0x440 driver_probe_device+0x60/0x160 __device_attach_driver+0x1a0/0x2a0 bus_for_each_drv+0x100/0x1a0 __device_attach+0x174/0x350 device_initial_probe+0x90/0xb0 bus_probe_device+0x4c/0x120 device_add+0xdec/0x116c platform_device_add+0x354/0x598 Remove the assignment of adap->rc to NULL to let cec_delete_adapter() free the allocated rc device after last user of the cec device exits to fix the kmemleak.

Affected packages & fixed versions

Affected products (as reported)

References

• https://git.kernel.org/stable/c/954ee95a03b4d31d4505591bfaba02c24b75776b
• https://git.kernel.org/stable/c/f28a8e1ba4d67a18e4662e5acefd5a4389322366
• https://git.kernel.org/stable/c/695063fc57574dd117b1bc750ca189cf03a2caad
• https://git.kernel.org/stable/c/cca2407794795cecff7f8e5f5a79f4ef6b1d6f6c
• https://git.kernel.org/stable/c/a24ba0653f7154e671dc8d2bf64682ab2d042792