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a8a717963f
Some kernels builds might inline vfs_getattr call within fstat
syscall code path, so fentry/vfs_getattr trampoline is not called.
Add security_inode_getattr to allowlist and switch the d_path test stat
trampoline to security_inode_getattr.
Keeping dentry_open and filp_close, because they are in their own
files, so unlikely to be inlined, but in case they are, adding
security_file_open.
Adding flags that indicate trampolines were called and failing
the test if any of them got missed, so it's easier to identify
the issue next time.
Fixes: e4d1af4b16 ("selftests/bpf: Add test for d_path helper")
Suggested-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200918112338.2618444-1-jolsa@kernel.org
66 lines
1.2 KiB
C
66 lines
1.2 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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int called_stat = 0;
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int called_close = 0;
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SEC("fentry/security_inode_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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called_stat = 1;
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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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called_close = 1;
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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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