From 89b096898a8450b0a5b97d521e000ae9f94f81f9 Mon Sep 17 00:00:00 2001 From: Daniel Borkmann Date: Thu, 27 Jul 2017 21:02:46 +0200 Subject: [PATCH] bpf: don't indicate success when copy_from_user fails err in bpf_prog_get_info_by_fd() still holds 0 at that time from prior check_uarg_tail_zero() check. Explicitly return -EFAULT instead, so user space can be notified of buggy behavior. Fixes: 1e2709769086 ("bpf: Add BPF_OBJ_GET_INFO_BY_FD") Signed-off-by: Daniel Borkmann Acked-by: Martin KaFai Lau Signed-off-by: David S. Miller --- kernel/bpf/syscall.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 045646d..84bb399 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -1289,7 +1289,7 @@ static int bpf_prog_get_info_by_fd(struct bpf_prog *prog, info_len = min_t(u32, sizeof(info), info_len); if (copy_from_user(&info, uinfo, info_len)) - return err; + return -EFAULT; info.type = prog->type; info.id = prog->aux->id; -- 2.7.4