1 /* Copyright (c) 2016 Facebook 2 * 3 * This program is free software; you can redistribute it and/or 4 * modify it under the terms of version 2 of the GNU General Public 5 * License as published by the Free Software Foundation. 6 */ 7 #include <linux/version.h> 8 #include <linux/ptrace.h> 9 #include <uapi/linux/bpf.h> 10 #include "bpf_helpers.h" 11 12 #define _(P) ({typeof(P) val = 0; bpf_probe_read(&val, sizeof(val), &P); val;}) 13 14 SEC("kprobe/__set_task_comm") prog(struct pt_regs * ctx)15int prog(struct pt_regs *ctx) 16 { 17 struct signal_struct *signal; 18 struct task_struct *tsk; 19 char oldcomm[16] = {}; 20 char newcomm[16] = {}; 21 u16 oom_score_adj; 22 u32 pid; 23 24 tsk = (void *)PT_REGS_PARM1(ctx); 25 26 pid = _(tsk->pid); 27 bpf_probe_read(oldcomm, sizeof(oldcomm), &tsk->comm); 28 bpf_probe_read(newcomm, sizeof(newcomm), (void *)PT_REGS_PARM2(ctx)); 29 signal = _(tsk->signal); 30 oom_score_adj = _(signal->oom_score_adj); 31 return 0; 32 } 33 34 SEC("kprobe/urandom_read") prog2(struct pt_regs * ctx)35int prog2(struct pt_regs *ctx) 36 { 37 return 0; 38 } 39 40 char _license[] SEC("license") = "GPL"; 41 u32 _version SEC("version") = LINUX_VERSION_CODE; 42