Commit 62e3d421 authored by Jordan Niethe's avatar Jordan Niethe Committed by Michael Ellerman
Browse files

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: default avatarJordan Niethe <jniethe5@gmail.com>
Reviewed-by: default avatarChristophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210609013431.9805-7-jniethe5@gmail.com
parent bc33cfdb

arch/powerpc/net/bpf_jit_comp.c

+1 −0
Original line number Diff line number Diff line
@@ -237,6 +237,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *fp) 
	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: