summaryrefslogtreecommitdiff
path: root/samples/bpf/test_probe_write_user_kern.c
AgeCommit message (Collapse)Author
2019-11-02bpf, samples: Use bpf_probe_read_user where appropriateDaniel Borkmann
Use bpf_probe_read_user() helper instead of bpf_probe_read() for samples that attach to kprobes probing on user addresses. 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/5b0144b3f8e031ec5e2438bd7de8d7877e63bf2f.1572649915.git.daniel@iogearbox.net
2019-10-08selftests/bpf: Split off tracing-only helpers into bpf_tracing.hAndrii Nakryiko
Split-off PT_REGS-related helpers into bpf_tracing.h header. Adjust selftests and samples to include it where necessary. Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/20191008175942.1769476-5-andriin@fb.com
2016-07-25samples/bpf: Add test/example of using bpf_probe_write_user bpf helperSargun Dhillon
This example shows using a kprobe to act as a dnat mechanism to divert traffic for arbitrary endpoints. It rewrite the arguments to a syscall while they're still in userspace, and before the syscall has a chance to copy the argument into kernel space. Although this is an example, it also acts as a test because the mapped address is 255.255.255.255:555 -> real address, and that's not a legal address to connect to. If the helper is broken, the example will fail on the intermediate steps, as well as the final step to verify the rewrite of userspace memory succeeded. Signed-off-by: Sargun Dhillon <sargun@sargun.me> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>