1 // SPDX-License-Identifier: GPL-2.0 2 /* Copyright 2022 Sony Group Corporation */ 3 #include <vmlinux.h> 4 5 #include <bpf/bpf_core_read.h> 6 #include <bpf/bpf_helpers.h> 7 #include <bpf/bpf_tracing.h> 8 #include "bpf_misc.h" 9 10 int arg1 = 0; 11 unsigned long arg2 = 0; 12 unsigned long arg3 = 0; 13 unsigned long arg4_cx = 0; 14 unsigned long arg4 = 0; 15 unsigned long arg5 = 0; 16 17 int arg1_core = 0; 18 unsigned long arg2_core = 0; 19 unsigned long arg3_core = 0; 20 unsigned long arg4_core_cx = 0; 21 unsigned long arg4_core = 0; 22 unsigned long arg5_core = 0; 23 24 int option_syscall = 0; 25 unsigned long arg2_syscall = 0; 26 unsigned long arg3_syscall = 0; 27 unsigned long arg4_syscall = 0; 28 unsigned long arg5_syscall = 0; 29 30 const volatile pid_t filter_pid = 0; 31 32 SEC("kprobe/" SYS_PREFIX "sys_prctl") 33 int BPF_KPROBE(handle_sys_prctl) 34 { 35 struct pt_regs *real_regs; 36 pid_t pid = bpf_get_current_pid_tgid() >> 32; 37 unsigned long tmp = 0; 38 39 if (pid != filter_pid) 40 return 0; 41 42 real_regs = PT_REGS_SYSCALL_REGS(ctx); 43 44 /* test for PT_REGS_PARM */ 45 46 #if !defined(bpf_target_arm64) && !defined(bpf_target_s390) 47 bpf_probe_read_kernel(&tmp, sizeof(tmp), &PT_REGS_PARM1_SYSCALL(real_regs)); 48 #endif 49 arg1 = tmp; 50 bpf_probe_read_kernel(&arg2, sizeof(arg2), &PT_REGS_PARM2_SYSCALL(real_regs)); 51 bpf_probe_read_kernel(&arg3, sizeof(arg3), &PT_REGS_PARM3_SYSCALL(real_regs)); 52 bpf_probe_read_kernel(&arg4_cx, sizeof(arg4_cx), &PT_REGS_PARM4(real_regs)); 53 bpf_probe_read_kernel(&arg4, sizeof(arg4), &PT_REGS_PARM4_SYSCALL(real_regs)); 54 bpf_probe_read_kernel(&arg5, sizeof(arg5), &PT_REGS_PARM5_SYSCALL(real_regs)); 55 56 /* test for the CORE variant of PT_REGS_PARM */ 57 arg1_core = PT_REGS_PARM1_CORE_SYSCALL(real_regs); 58 arg2_core = PT_REGS_PARM2_CORE_SYSCALL(real_regs); 59 arg3_core = PT_REGS_PARM3_CORE_SYSCALL(real_regs); 60 arg4_core_cx = PT_REGS_PARM4_CORE(real_regs); 61 arg4_core = PT_REGS_PARM4_CORE_SYSCALL(real_regs); 62 arg5_core = PT_REGS_PARM5_CORE_SYSCALL(real_regs); 63 64 return 0; 65 } 66 67 SEC("kprobe/" SYS_PREFIX "sys_prctl") 68 int BPF_KPROBE_SYSCALL(prctl_enter, int option, unsigned long arg2, 69 unsigned long arg3, unsigned long arg4, unsigned long arg5) 70 { 71 pid_t pid = bpf_get_current_pid_tgid() >> 32; 72 73 if (pid != filter_pid) 74 return 0; 75 76 option_syscall = option; 77 arg2_syscall = arg2; 78 arg3_syscall = arg3; 79 arg4_syscall = arg4; 80 arg5_syscall = arg5; 81 return 0; 82 } 83 84 char _license[] SEC("license") = "GPL"; 85