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author | Yonghong Song <yhs@fb.com> | 2020-06-30 10:12:41 -0700 |
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committer | Daniel Borkmann <daniel@iogearbox.net> | 2020-06-30 22:21:29 +0200 |
commit | d923021c2ce12acb50dc7086a1bf66eed82adf6a (patch) | |
tree | ab388fa92b8b8bf4d3be8683567ee1b3788ebbf9 /kernel | |
parent | 01c66c48d4f0825a202d4163800b706a1d2ec7ad (diff) | |
download | linux-d923021c2ce12acb50dc7086a1bf66eed82adf6a.tar.gz linux-d923021c2ce12acb50dc7086a1bf66eed82adf6a.tar.bz2 linux-d923021c2ce12acb50dc7086a1bf66eed82adf6a.zip |
bpf: Add tests for PTR_TO_BTF_ID vs. null comparison
Add two tests for PTR_TO_BTF_ID vs. null ptr comparison,
one for PTR_TO_BTF_ID in the ctx structure and the
other for PTR_TO_BTF_ID after one level pointer chasing.
In both cases, the test ensures condition is not
removed.
For example, for this test
struct bpf_fentry_test_t {
struct bpf_fentry_test_t *a;
};
int BPF_PROG(test7, struct bpf_fentry_test_t *arg)
{
if (arg == 0)
test7_result = 1;
return 0;
}
Before the previous verifier change, we have xlated codes:
int test7(long long unsigned int * ctx):
; int BPF_PROG(test7, struct bpf_fentry_test_t *arg)
0: (79) r1 = *(u64 *)(r1 +0)
; int BPF_PROG(test7, struct bpf_fentry_test_t *arg)
1: (b4) w0 = 0
2: (95) exit
After the previous verifier change, we have:
int test7(long long unsigned int * ctx):
; int BPF_PROG(test7, struct bpf_fentry_test_t *arg)
0: (79) r1 = *(u64 *)(r1 +0)
; if (arg == 0)
1: (55) if r1 != 0x0 goto pc+4
; test7_result = 1;
2: (18) r1 = map[id:6][0]+48
4: (b7) r2 = 1
5: (7b) *(u64 *)(r1 +0) = r2
; int BPF_PROG(test7, struct bpf_fentry_test_t *arg)
6: (b4) w0 = 0
7: (95) exit
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200630171241.2523875-1-yhs@fb.com
Diffstat (limited to 'kernel')
0 files changed, 0 insertions, 0 deletions