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| author | Philo Lu <lulie@linux.alibaba.com> | 2024-04-05 10:55:34 +0800 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2024-04-05 10:31:17 -0700 |
| commit | 0a525621b7e5b49202b19d8f75382c6778fdd0c1 (patch) | |
| tree | 15aca0b681bfa152ff7768390965942dcbe6026b /include/linux | |
| parent | 58babe27180c8d4cb54d831589cf801bd9268876 (diff) | |
| download | linux-stable-0a525621b7e5b49202b19d8f75382c6778fdd0c1.tar.gz linux-stable-0a525621b7e5b49202b19d8f75382c6778fdd0c1.tar.bz2 linux-stable-0a525621b7e5b49202b19d8f75382c6778fdd0c1.zip | |
bpf: store both map ptr and state in bpf_insn_aux_data
Currently, bpf_insn_aux_data->map_ptr_state is used to store either
map_ptr or its poison state (i.e., BPF_MAP_PTR_POISON). Thus
BPF_MAP_PTR_POISON must be checked before reading map_ptr. In certain
cases, we may need valid map_ptr even in case of poison state.
This will be explained in next patch with bpf_for_each_map_elem()
helper.
This patch changes map_ptr_state into a new struct including both map
pointer and its state (poison/unpriv). It's in the same union with
struct bpf_loop_inline_state, so there is no extra memory overhead.
Besides, macros BPF_MAP_PTR_UNPRIV/BPF_MAP_PTR_POISON/BPF_MAP_PTR are no
longer needed.
This patch does not change any existing functionality.
Signed-off-by: Philo Lu <lulie@linux.alibaba.com>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20240405025536.18113-2-lulie@linux.alibaba.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/bpf_verifier.h | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/include/linux/bpf_verifier.h b/include/linux/bpf_verifier.h index 7cb1b75eee38..36d19cd32eb5 100644 --- a/include/linux/bpf_verifier.h +++ b/include/linux/bpf_verifier.h @@ -502,6 +502,13 @@ struct bpf_loop_inline_state { u32 callback_subprogno; /* valid when fit_for_inline is true */ }; +/* pointer and state for maps */ +struct bpf_map_ptr_state { + struct bpf_map *map_ptr; + bool poison; + bool unpriv; +}; + /* Possible states for alu_state member. */ #define BPF_ALU_SANITIZE_SRC (1U << 0) #define BPF_ALU_SANITIZE_DST (1U << 1) @@ -514,7 +521,7 @@ struct bpf_loop_inline_state { struct bpf_insn_aux_data { union { enum bpf_reg_type ptr_type; /* pointer type for load/store insns */ - unsigned long map_ptr_state; /* pointer/poison value for maps */ + struct bpf_map_ptr_state map_ptr_state; s32 call_imm; /* saved imm field of call insn */ u32 alu_limit; /* limit for add/sub register with pointer */ struct { |