CVE-2026-92483

In the Linux kernel, the following vulnerability has been resolved:

liveupdate: Remember FLB retrieve() status

LUO keeps track of successful retrieve attempts on an FLB. It does so

to avoid multiple retrievals of the same FLB. Multiple retrievals cause

problems because once the FLB is retrieved, the serialized data

structures are likely freed and the FLB is likely in a very different

state from what the code expects.

All this works well when retrieve succeeds. When it fails,

luo_flb_retrieve_one() returns the error immediately, without ever

storing anywhere that a retrieve was attempted or what its error code

was. If the user attempts to retrieve another file registered with the

same FLB, LUO will attempt to call the FLB's retrieve() callback again.

The retry is problematic for much of the same reasons listed above. The

FLB is likely in a very different state than what the retrieve logic

normally expects (e.g. some KHO pages may have already been restored and

freed).

There is no sane way of attempting the retrieve again. Remember the

error retrieve returned and directly return it on a retry.

This is done by changing the retrieved bool to a retrieve_status

integer. A value of 0 means retrieve was never attempted, a positive

value means it succeeded, and a negative value means it failed and the

error code is the value.

This is similar to commit f85b1c6af5bc ("liveupdate: luo_file: remember

retrieve() status") which did the same for LUO files.