From d2a3b7c5becc3992f8e7d2b9bf5eacceeedb9a48 Mon Sep 17 00:00:00 2001 From: Hou Tao Date: Wed, 9 Mar 2022 20:33:20 +0800 Subject: bpf: Fix net.core.bpf_jit_harden race It is the bpf_jit_harden counterpart to commit 60b58afc96c9 ("bpf: fix net.core.bpf_jit_enable race"). bpf_jit_harden will be tested twice for each subprog if there are subprogs in bpf program and constant blinding may increase the length of program, so when running "./test_progs -t subprogs" and toggling bpf_jit_harden between 0 and 2, jit_subprogs may fail because constant blinding increases the length of subprog instructions during extra passs. So cache the value of bpf_jit_blinding_enabled() during program allocation, and use the cached value during constant blinding, subprog JITing and args tracking of tail call. Signed-off-by: Hou Tao Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20220309123321.2400262-4-houtao1@huawei.com --- include/linux/filter.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include') diff --git a/include/linux/filter.h b/include/linux/filter.h index 05ed9bd31b45..ed0c0ff42ad5 100644 --- a/include/linux/filter.h +++ b/include/linux/filter.h @@ -566,6 +566,7 @@ struct bpf_prog { gpl_compatible:1, /* Is filter GPL compatible? */ cb_access:1, /* Is control block accessed? */ dst_needed:1, /* Do we need dst entry? */ + blinding_requested:1, /* needs constant blinding */ blinded:1, /* Was blinded */ is_func:1, /* program is a bpf function */ kprobe_override:1, /* Do we override a kprobe? */ -- cgit v1.2.3