diff options
author | Daniel Borkmann <daniel@iogearbox.net> | 2019-11-02 00:18:00 +0100 |
---|---|---|
committer | Alexei Starovoitov <ast@kernel.org> | 2019-11-02 12:39:12 -0700 |
commit | 6e07a6341277a1dbdf5ed0c41921033c234c1635 (patch) | |
tree | 439779300ddbf6452ae0a9ca1e00e6e043d2ebfb | |
parent | 6ae08ae3dea2cfa03dd3665a3c8475c2d429ef47 (diff) | |
download | linux-6e07a6341277a1dbdf5ed0c41921033c234c1635.tar.bz2 |
bpf: Switch BPF probe insns to bpf_probe_read_kernel
Commit 2a02759ef5f8 ("bpf: Add support for BTF pointers to interpreter")
explicitly states that the pointer to BTF object is a pointer to a kernel
object or NULL. Therefore we should also switch to using the strict kernel
probe helper which is restricted to kernel addresses only when architectures
have non-overlapping address spaces.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/d2b90827837685424a4b8008dfe0460558abfada.1572649915.git.daniel@iogearbox.net
-rw-r--r-- | kernel/bpf/core.c | 9 |
1 files changed, 5 insertions, 4 deletions
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index 8d3fbc86ca5e..df82d5a42b23 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -1306,11 +1306,12 @@ bool bpf_opcode_in_insntable(u8 code) } #ifndef CONFIG_BPF_JIT_ALWAYS_ON -u64 __weak bpf_probe_read(void * dst, u32 size, const void * unsafe_ptr) +u64 __weak bpf_probe_read_kernel(void *dst, u32 size, const void *unsafe_ptr) { memset(dst, 0, size); return -EFAULT; } + /** * __bpf_prog_run - run eBPF program on a given context * @regs: is the array of MAX_BPF_EXT_REG eBPF pseudo-registers @@ -1566,9 +1567,9 @@ out: LDST(W, u32) LDST(DW, u64) #undef LDST -#define LDX_PROBE(SIZEOP, SIZE) \ - LDX_PROBE_MEM_##SIZEOP: \ - bpf_probe_read(&DST, SIZE, (const void *)(long) SRC); \ +#define LDX_PROBE(SIZEOP, SIZE) \ + LDX_PROBE_MEM_##SIZEOP: \ + bpf_probe_read_kernel(&DST, SIZE, (const void *)(long) SRC); \ CONT; LDX_PROBE(B, 1) LDX_PROBE(H, 2) |