Re: [PATCH arm64-next] net: bpf: arm64: fix module memory leak when JIT image build fails

[Catalin Marinas]

On Thu, Sep 11, 2014 at 11:45:13AM +0100, Will Deacon wrote:
> On Thu, Sep 11, 2014 at 10:36:48AM +0100, Daniel Borkmann wrote:
> > On ARM64, when the BPF JIT compiler fills the JIT image body with
> > opcodes during translation of eBPF into ARM64 opcodes, we may fail
> > for several reasons during that phase: one being that we jump to
> > the notyet label for not yet supported eBPF instructions such as
> > BPF_ST. In that case we only free offsets, but not the actual
> > allocated target image where opcodes are being stored. Fix it by
> > calling module_free() on dismantle time in case of errors.
> > 
> > Signed-off-by: Daniel Borkmann <dborkman@xxxxxxxxxx>
> > Cc: Zi Shen Lim <zlim.lnx@xxxxxxxxx>
> > Cc: Alexei Starovoitov <ast@xxxxxxxxxxxx>
> > Cc: Will Deacon <will.deacon@xxxxxxx>
> > ---
> >  [ Compile-tested only. ]
> > 
> >  arch/arm64/net/bpf_jit_comp.c | 4 +++-
> >  1 file changed, 3 insertions(+), 1 deletion(-)
> > 
> > diff --git a/arch/arm64/net/bpf_jit_comp.c b/arch/arm64/net/bpf_jit_comp.c
> > index 38c4296..7ae3354 100644
> > --- a/arch/arm64/net/bpf_jit_comp.c
> > +++ b/arch/arm64/net/bpf_jit_comp.c
> > @@ -651,8 +651,10 @@ void bpf_int_jit_compile(struct bpf_prog *prog)
> >  	build_prologue(&ctx);
> >  
> >  	ctx.body_offset = ctx.idx;
> > -	if (build_body(&ctx))
> > +	if (build_body(&ctx)) {
> > +		module_free(NULL, ctx.image);
> >  		goto out;
> > +	}
> >  
> 
> Looks good to me:
> 
>   Acked-by: Will Deacon <will.deacon@xxxxxxx>
> 
> Catalin, can you apply this on the for-next/core branch, please?

Applied, thanks.

-- 
Catalin

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