From: =?UTF-8?q?Holger=20Hoffst=C3=A4tte?= <holger@applied-asynchrony.com>
Date: Fri, 13 Jan 2023 16:40:23 +0100
Subject: [PATCH] bpftool: Always disable stack protection for BPF objects
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References: bsc#1012628
Patch-mainline: 6.2.3
Git-commit: 878625e1c7a10dfbb1fdaaaae2c4d2a58fbce627
[ Upstream commit 878625e1c7a10dfbb1fdaaaae2c4d2a58fbce627 ]
When the clang toolchain has stack protection enabled in order to be
consistent with gcc - which just happens to be the case on Gentoo -
the bpftool build fails:
[...]
clang \
-I. \
-I/tmp/portage/dev-util/bpftool-6.0.12/work/linux-6.0/tools/include/uapi/ \
-I/tmp/portage/dev-util/bpftool-6.0.12/work/linux-6.0/tools/bpf/bpftool/bootstrap/libbpf/include \
-g -O2 -Wall -target bpf -c skeleton/pid_iter.bpf.c -o pid_iter.bpf.o
clang \
-I. \
-I/tmp/portage/dev-util/bpftool-6.0.12/work/linux-6.0/tools/include/uapi/ \
-I/tmp/portage/dev-util/bpftool-6.0.12/work/linux-6.0/tools/bpf/bpftool/bootstrap/libbpf/include \
-g -O2 -Wall -target bpf -c skeleton/profiler.bpf.c -o profiler.bpf.o
skeleton/profiler.bpf.c:40:14: error: A call to built-in function '__stack_chk_fail' is not supported.
int BPF_PROG(fentry_XXX)
^
skeleton/profiler.bpf.c:94:14: error: A call to built-in function '__stack_chk_fail' is not supported.
int BPF_PROG(fexit_XXX)
^
2 errors generated.
[...]
Since stack-protector makes no sense for the BPF bits just unconditionally
disable it.
Bug: https://bugs.gentoo.org/890638
Signed-off-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/74cd9d2e-6052-312a-241e-2b514a75c92c@applied-asynchrony.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
tools/bpf/bpftool/Makefile | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/tools/bpf/bpftool/Makefile b/tools/bpf/bpftool/Makefile
index f610e184..270066af 100644
--- a/tools/bpf/bpftool/Makefile
+++ b/tools/bpf/bpftool/Makefile
@@ -215,7 +215,8 @@ $(OUTPUT)%.bpf.o: skeleton/%.bpf.c $(OUTPUT)vmlinux.h $(LIBBPF_BOOTSTRAP)
-I$(or $(OUTPUT),.) \
-I$(srctree)/tools/include/uapi/ \
-I$(LIBBPF_BOOTSTRAP_INCLUDE) \
- -g -O2 -Wall -target bpf -c $< -o $@
+ -g -O2 -Wall -fno-stack-protector \
+ -target bpf -c $< -o $@
$(Q)$(LLVM_STRIP) -g $@
$(OUTPUT)%.skel.h: $(OUTPUT)%.bpf.o $(BPFTOOL_BOOTSTRAP)
--
2.35.3