Commit 286aad3c authored by Daniel Borkmann's avatar Daniel Borkmann Committed by David S. Miller
Browse files

net: bpf: be friendly to kmemcheck 



Reported by Mikulas Patocka, kmemcheck currently barks out a
false positive since we don't have special kmemcheck annotation
for bitfields used in bpf_prog structure.

We currently have jited:1, len:31 and thus when accessing len
while CONFIG_KMEMCHECK enabled, kmemcheck throws a warning that
we're reading uninitialized memory.

As we don't need the whole bit universe for pages member, we
can just split it to u16 and use a bool flag for jited instead
of a bitfield.

Signed-off-by: default avatarMikulas Patocka <mpatocka@redhat.com>
Signed-off-by: default avatarDaniel Borkmann <dborkman@redhat.com>
Acked-by: default avatarAlexei Starovoitov <ast@plumgrid.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 55309dd3

arch/arm/net/bpf_jit_32.c

+1 −1
Original line number Diff line number Diff line
@@ -933,7 +933,7 @@ void bpf_jit_compile(struct bpf_prog *fp) 


	set_memory_ro((unsigned long)header, header->pages);

	fp->bpf_func = (void *)ctx.target;

	fp->jited = 1;

	fp->jited = true;

out:

	kfree(ctx.offsets);

	return;

arch/mips/net/bpf_jit.c

+1 −1
Original line number Diff line number Diff line
@@ -1417,7 +1417,7 @@ void bpf_jit_compile(struct bpf_prog *fp) 
		bpf_jit_dump(fp->len, alloc_size, 2, ctx.target);



	fp->bpf_func = (void *)ctx.target;

	fp->jited = 1;

	fp->jited = true;



out:

	kfree(ctx.offsets);

arch/powerpc/net/bpf_jit_comp.c

+1 −1
Original line number Diff line number Diff line
@@ -686,7 +686,7 @@ void bpf_jit_compile(struct bpf_prog *fp) 
		((u64 *)image)[0] = (u64)code_base;

		((u64 *)image)[1] = local_paca->kernel_toc;

		fp->bpf_func = (void *)image;

		fp->jited = 1;

		fp->jited = true;

	}

out:

	kfree(addrs);

arch/s390/net/bpf_jit_comp.c

+1 −1
Original line number Diff line number Diff line
@@ -842,7 +842,7 @@ void bpf_jit_compile(struct bpf_prog *fp) 
	if (jit.start) {

		set_memory_ro((unsigned long)header, header->pages);

		fp->bpf_func = (void *) jit.start;

		fp->jited = 1;

		fp->jited = true;

	}

out:

	kfree(addrs);

arch/sparc/net/bpf_jit_comp.c

+1 −1
Original line number Diff line number Diff line
@@ -801,7 +801,7 @@ cond_branch: f_offset = addrs[i + filter[i].jf]; 
	if (image) {

		bpf_flush_icache(image, image + proglen);

		fp->bpf_func = (void *)image;

		fp->jited = 1;

		fp->jited = true;

	}

out:

	kfree(addrs);

CRA Git | Maintained and supported by SUSTech CRA and CCSE