The man who allegedly attacked and stabbed Tory Lanez in jail is serving a life sentence for a homicide cost … and this wasn’t his first violent incident behind bars.

The California Division of Corrections and Rehabilitation tells TMZ … Tory was allegedly attacked by fellow inmate Santino Casio round 7:20 AM on Monday morning in a housing unit at California Correctional Establishment (CCI) in Tehachapi.

We’re advised jail workers instantly responded, known as 911 and began giving Tory medical help earlier than transporting him to a hospital for additional remedy.

Tory’s camp says he was stabbed 14 instances and suffered collapsed lungs.

CDCR says 42-year-old Casio has been positioned in restricted housing pending an investigation.

We’re advised Casio was sentenced to life with the potential of parole for second-degree homicide, first-degree tried homicide, private use of a harmful or lethal weapon, and inflicting nice bodily damage.

Whereas incarcerated, CDCR says Casio was sentenced to 6 years for assaulting a prisoner with a lethal weapon or power more likely to trigger nice bodily damage.

We’re advised he was additionally sentenced to 2 years for possession/manufacture of a lethal weapon by a prisoner.