From: Toke Høiland-Jørgensen Date: Mon, 16 Dec 2019 10:38:19 +0000 (+0100) Subject: samples/bpf: Set -fno-stack-protector when building BPF programs X-Git-Tag: v5.5.6~253 X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=d0f320b013efb52cee2ba1b7da85658d58f56dc5;p=users%2Fdwmw2%2Flinux.git samples/bpf: Set -fno-stack-protector when building BPF programs [ Upstream commit 450278977acbf494a20367c22fbb38729772d1fc ] It seems Clang can in some cases turn on stack protection by default, which doesn't work with BPF. This was reported once before[0], but it seems the flag to explicitly turn off the stack protector wasn't added to the Makefile, so do that now. The symptom of this is compile errors like the following: error: :0:0: in function bpf_prog1 i32 (%struct.__sk_buff*): A call to built-in function '__stack_chk_fail' is not supported. [0] https://www.spinics.net/lists/netdev/msg556400.html Signed-off-by: Toke Høiland-Jørgensen Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20191216103819.359535-1-toke@redhat.com Signed-off-by: Sasha Levin --- diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile index c0147a8cf1882..06ebe3104cc03 100644 --- a/samples/bpf/Makefile +++ b/samples/bpf/Makefile @@ -236,6 +236,7 @@ BTF_LLVM_PROBE := $(shell echo "int main() { return 0; }" | \ readelf -S ./llvm_btf_verify.o | grep BTF; \ /bin/rm -f ./llvm_btf_verify.o) +BPF_EXTRA_CFLAGS += -fno-stack-protector ifneq ($(BTF_LLVM_PROBE),) BPF_EXTRA_CFLAGS += -g else