From 62e3d4210ac9c35783d0e8fc306df4239c540a79 Mon Sep 17 00:00:00 2001 From: Jordan Niethe Date: Wed, 9 Jun 2021 11:34:28 +1000 Subject: [PATCH] powerpc/bpf: Write protect JIT code Add the necessary call to bpf_jit_binary_lock_ro() to remove write and add exec permissions to the JIT image after it has finished being written. Without CONFIG_STRICT_MODULE_RWX the image will be writable and executable until the call to bpf_jit_binary_lock_ro(). Signed-off-by: Jordan Niethe Reviewed-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20210609013431.9805-7-jniethe5@gmail.com --- arch/powerpc/net/bpf_jit_comp.c | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/powerpc/net/bpf_jit_comp.c b/arch/powerpc/net/bpf_jit_comp.c index 6c8c268e4fe8..53aefee3fe70 100644 --- a/arch/powerpc/net/bpf_jit_comp.c +++ b/arch/powerpc/net/bpf_jit_comp.c @@ -237,6 +237,7 @@ skip_codegen_passes: fp->jited_len = alloclen; bpf_flush_icache(bpf_hdr, (u8 *)bpf_hdr + (bpf_hdr->pages * PAGE_SIZE)); + bpf_jit_binary_lock_ro(bpf_hdr); if (!fp->is_func || extra_pass) { bpf_prog_fill_jited_linfo(fp, addrs); out_addrs: