In the Linux kernel, the following vulnerability has been resolved:
scsi: target: tcmu: Fix possible page UAF
tcmutrygetdatapage() looks up pages under cmdrlock, but it does not take refcount properly and just returns page pointer. When tcmutrygetdatapage() returns, the returned page may have been freed by tcmublocks_release().
We need to getpage() under cmdrlock to avoid concurrent tcmublocksrelease().