In the Linux kernel, the following vulnerability has been resolved:
coresight: holding cscfg_csdev_lock while removing cscfg from csdev
There'll be possible race scenario for coresight config:
CPU0 CPU1
(perf enable) load module
cscfg_load_config_sets()
activate config. // sysfs
(sys_active_cnt == 1)
...
cscfg_csdev_enable_active_config()
lock(csdev->cscfg_csdev_lock)
deactivate config // sysfs
(sys_activec_cnt == 0)
cscfg_unload_config_sets()
<iterating config_csdev_list> cscfg_remove_owned_csdev_configs()
// here load config activate by CPU1
unlock(csdev->cscfg_csdev_lock)
iterating config_csdev_list could be raced with config_csdev_list's
entry delete.
To resolve this race , hold csdev->cscfg_csdev_lock() while
cscfg_remove_owned_csdev_configs()
