1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Hook into 'openat' syscall entry tracepoint 4 * 5 * Test it with: 6 * 7 * perf trace -e tools/perf/examples/bpf/sys_enter_openat.c cat /etc/passwd > /dev/null 8 * 9 * It'll catch some openat syscalls related to the dynamic linked and 10 * the last one should be the one for '/etc/passwd'. 11 * 12 * The syscall_enter_openat_args can be used to get the syscall fields 13 * and use them for filtering calls, i.e. use in expressions for 14 * the return value. 15 */ 16 17 #include <bpf.h> 18 19 struct syscall_enter_openat_args { 20 unsigned long long unused; 21 long syscall_nr; 22 long dfd; 23 char *filename_ptr; 24 long flags; 25 long mode; 26 }; 27 28 int syscall_enter(openat)(struct syscall_enter_openat_args *args) 29 { 30 return 1; 31 } 32 33 license(GPL);