From c7f54ef43499f9b10771459058f1361d37b3e3e1 Mon Sep 17 00:00:00 2001 From: Kui-Feng Lee Date: Tue, 2 May 2023 11:14:18 -0700 Subject: bpf: Print a warning only if writing to unprivileged_bpf_disabled. [ Upstream commit fedf99200ab086c42a572fca1d7266b06cdc3e3f ] Only print the warning message if you are writing to "/proc/sys/kernel/unprivileged_bpf_disabled". The kernel may print an annoying warning when you read "/proc/sys/kernel/unprivileged_bpf_disabled" saying WARNING: Unprivileged eBPF is enabled with eIBRS on, data leaks possible via Spectre v2 BHB attacks! However, this message is only meaningful when the feature is disabled or enabled. Signed-off-by: Kui-Feng Lee Signed-off-by: Andrii Nakryiko Acked-by: Yonghong Song Link: https://lore.kernel.org/bpf/20230502181418.308479-1-kuifeng@meta.com Signed-off-by: Sasha Levin --- kernel/bpf/syscall.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'kernel') diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index f1c8733f76b8..5524fcf6fb2a 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -5394,7 +5394,8 @@ static int bpf_unpriv_handler(struct ctl_table *table, int write, *(int *)table->data = unpriv_enable; } - unpriv_ebpf_notify(unpriv_enable); + if (write) + unpriv_ebpf_notify(unpriv_enable); return ret; } -- cgit v1.2.3