From: Daniel Borkmann daniel@iogearbox.net
commit 47cc0ed574abcbbde0cf143ddb21a0baed1aa2df upstream.
Given bpf_probe_read{,str}() BPF helpers are now only available under CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE, we need to add the drop-in replacements of bpf_probe_read_{kernel,user}_str() to do_refine_retval_range() as well to avoid hitting the same issue as in 849fa50662fbc ("bpf/verifier: refine retval R0 state for bpf_get_stack helper").
Signed-off-by: Daniel Borkmann daniel@iogearbox.net Signed-off-by: Alexei Starovoitov ast@kernel.org Acked-by: John Fastabend john.fastabend@gmail.com Acked-by: Yonghong Song yhs@fb.com Link: https://lore.kernel.org/bpf/20200515101118.6508-3-daniel@iogearbox.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- kernel/bpf/verifier.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
--- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -4113,7 +4113,9 @@ static int do_refine_retval_range(struct
if (ret_type != RET_INTEGER || (func_id != BPF_FUNC_get_stack && - func_id != BPF_FUNC_probe_read_str)) + func_id != BPF_FUNC_probe_read_str && + func_id != BPF_FUNC_probe_read_kernel_str && + func_id != BPF_FUNC_probe_read_user_str)) return 0;
/* Error case where ret is in interval [S32MIN, -1]. */