From 82c40543765b479e592036141356d7fdb2e84c00 Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Mon, 26 Sep 2022 17:33:39 +0200 Subject: [PATCH] bpf: Return value in kprobe get_func_ip only for entry address Changing return value of kprobe's version of bpf_get_func_ip to return zero if the attach address is not on the function's entry point. For kprobes attached in the middle of the function we can't easily get to the function address especially now with the CONFIG_X86_KERNEL_IBT support. If user cares about current IP for kprobes attached within the function body, they can get it with PT_REGS_IP(ctx). Suggested-by: Andrii Nakryiko Acked-by: Andrii Nakryiko Acked-by: Martynas Pumputis Signed-off-by: Jiri Olsa Link: https://lore.kernel.org/r/20220926153340.1621984-6-jolsa@kernel.org Signed-off-by: Alexei Starovoitov --- include/uapi/linux/bpf.h | 1 + 1 file changed, 1 insertion(+) diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index ead35f3..d6bd107 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -4951,6 +4951,7 @@ union bpf_attr { * Get address of the traced function (for tracing and kprobe programs). * Return * Address of the traced function. + * 0 for kprobes placed within the function (not at the entry). * * u64 bpf_get_attach_cookie(void *ctx) * Description