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| author | Hao Luo <haoluo@google.com> | 2021-12-16 16:31:50 -0800 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2021-12-18 13:27:41 -0800 |
| commit | 34d3a78c681e8e7844b43d1a2f4671a04249c821 (patch) | |
| tree | d0a60ddfc12cc916d80923b04d80f01ae69c1301 /kernel/bpf/syscall.c | |
| parent | cf9f2f8d62eca810afbd1ee6cc0800202b000e57 (diff) | |
| download | linux-34d3a78c681e8e7844b43d1a2f4671a04249c821.tar.bz2 | |
bpf: Make per_cpu_ptr return rdonly PTR_TO_MEM.
Tag the return type of {per, this}_cpu_ptr with RDONLY_MEM. The
returned value of this pair of helpers is kernel object, which
can not be updated by bpf programs. Previously these two helpers
return PTR_OT_MEM for kernel objects of scalar type, which allows
one to directly modify the memory. Now with RDONLY_MEM tagging,
the verifier will reject programs that write into RDONLY_MEM.
Fixes: 63d9b80dcf2c ("bpf: Introducte bpf_this_cpu_ptr()")
Fixes: eaa6bcb71ef6 ("bpf: Introduce bpf_per_cpu_ptr()")
Fixes: 4976b718c355 ("bpf: Introduce pseudo_btf_id")
Signed-off-by: Hao Luo <haoluo@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211217003152.48334-8-haoluo@google.com
Diffstat (limited to 'kernel/bpf/syscall.c')
0 files changed, 0 insertions, 0 deletions