Commit f1a41453 authored by Yafang Shao's avatar Yafang Shao Committed by Alexei Starovoitov
Browse files

bpf: Protect probed address based on kptr_restrict setting 



The probed address can be accessed by userspace through querying the task
file descriptor (fd). However, it is crucial to adhere to the kptr_restrict
setting and refrain from exposing the address if it is not permitted.

Signed-off-by: default avatarYafang Shao <laoar.shao@gmail.com>
Acked-by: default avatarJiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/r/20230709025630.3735-5-laoar.shao@gmail.com


Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent edd7f49b

kernel/trace/trace_kprobe.c

+4 −1
Original line number Diff line number Diff line
@@ -1551,7 +1551,10 @@ int bpf_get_kprobe_info(const struct perf_event *event, u32 *fd_type, 
	} else {

		*symbol = NULL;

		*probe_offset = 0;

		if (kallsyms_show_value(current_cred()))

			*probe_addr = (unsigned long)tk->rp.kp.addr;

		else

			*probe_addr = 0;

	}

	return 0;

}