From 3aab8884c9eb99189a3569ac4e6b205371c9ac0b Mon Sep 17 00:00:00 2001 From: Daniel Borkmann Date: Wed, 2 May 2018 20:12:22 +0200 Subject: [PATCH] bpf, x64: fix memleak when not converging after image While reviewing x64 JIT code, I noticed that we leak the prior allocated JIT image in the case where proglen != oldproglen during the JIT passes. Prior to the commit e0ee9c12157d ("x86: bpf_jit: fix two bugs in eBPF JIT compiler") we would just break out of the loop, and using the image as the JITed prog since it could only shrink in size anyway. After e0ee9c12157d, we would bail out to out_addrs label where we free addrs and jit_data but not the image coming from bpf_jit_binary_alloc(). Fixes: e0ee9c12157d ("x86: bpf_jit: fix two bugs in eBPF JIT compiler") Signed-off-by: Daniel Borkmann Acked-by: Alexei Starovoitov Acked-by: David S. Miller Signed-off-by: Alexei Starovoitov --- arch/x86/net/bpf_jit_comp.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c index abce27ceb411..9ae7b9372348 100644 --- a/arch/x86/net/bpf_jit_comp.c +++ b/arch/x86/net/bpf_jit_comp.c @@ -1236,6 +1236,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) for (pass = 0; pass < 20 || image; pass++) { proglen = do_jit(prog, addrs, image, oldproglen, &ctx); if (proglen <= 0) { +out_image: image = NULL; if (header) bpf_jit_binary_free(header); @@ -1246,8 +1247,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) if (proglen != oldproglen) { pr_err("bpf_jit: proglen=%d != oldproglen=%d\n", proglen, oldproglen); - prog = orig_prog; - goto out_addrs; + goto out_image; } break; }