e4d1af4b16
Adding test for d_path helper which is pretty much copied from Wenbo Zhang's test for bpf_get_fd_path, which never made it in. The test is doing fstat/close on several fd types, and verifies we got the d_path helper working on kernel probes for vfs_getattr/filp_close functions. Original-patch-by: Wenbo Zhang <ethercflow@gmail.com> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/20200825192124.710397-14-jolsa@kernel.org
59 lines
1.1 KiB
C
59 lines
1.1 KiB
C
// SPDX-License-Identifier: GPL-2.0
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#include "vmlinux.h"
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#include <bpf/bpf_helpers.h>
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#include <bpf/bpf_tracing.h>
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#define MAX_PATH_LEN 128
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#define MAX_FILES 7
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pid_t my_pid = 0;
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__u32 cnt_stat = 0;
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__u32 cnt_close = 0;
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char paths_stat[MAX_FILES][MAX_PATH_LEN] = {};
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char paths_close[MAX_FILES][MAX_PATH_LEN] = {};
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int rets_stat[MAX_FILES] = {};
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int rets_close[MAX_FILES] = {};
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SEC("fentry/vfs_getattr")
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int BPF_PROG(prog_stat, struct path *path, struct kstat *stat,
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__u32 request_mask, unsigned int query_flags)
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{
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pid_t pid = bpf_get_current_pid_tgid() >> 32;
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__u32 cnt = cnt_stat;
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int ret;
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if (pid != my_pid)
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return 0;
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if (cnt >= MAX_FILES)
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return 0;
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ret = bpf_d_path(path, paths_stat[cnt], MAX_PATH_LEN);
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rets_stat[cnt] = ret;
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cnt_stat++;
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return 0;
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}
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SEC("fentry/filp_close")
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int BPF_PROG(prog_close, struct file *file, void *id)
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{
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pid_t pid = bpf_get_current_pid_tgid() >> 32;
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__u32 cnt = cnt_close;
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int ret;
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if (pid != my_pid)
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return 0;
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if (cnt >= MAX_FILES)
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return 0;
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ret = bpf_d_path(&file->f_path,
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paths_close[cnt], MAX_PATH_LEN);
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rets_close[cnt] = ret;
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cnt_close++;
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return 0;
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}
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char _license[] SEC("license") = "GPL";
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