Entreprise française de cybersécurité depuis 2004
☎ 03 60 47 09 81 - info@securiteinfo.com
☎ 03 60 47 09 81 - info@securiteinfo.com
In the Linux kernel, the following vulnerability has been resolved:coresight: prevent deactivate active config while enabling the configWhile enable active config via cscfg_csdev_enable_active_config(),active config could be deactivated via configfs' sysfs interface.This could make UAF issue in below scenario:CPU0 CPU1(sysfs enable) load module cscfg_load_config_sets() activate config. // sysfs (sys_active_cnt == 1)...cscfg_csdev_enable_active_config()lock(csdev->cscfg_csdev_lock)// here load config activate by CPU1unlock(csdev->cscfg_csdev_lock) deactivate config // sysfs (sys_activec_cnt == 0) cscfg_unload_config_sets() unload module// access to config_desc which freed// while unloading module.cscfg_csdev_enable_configTo address this, use cscfg_config_desc's active_cnt as a reference count which will be holded when - activate the config. - enable the activated config.and put the module reference when config_active_cnt == 0.
No PoCs from references.
- https://github.com/w4zu/Debian_security