[PATCH v3 08/17] bpf: disable CFI in dispatcher functions
STALE2013d
REVIEWED: 1 (0M)
From: Sami Tolvanen <samitolvanen@google.com>
Date: 2021-03-23 20:41:13
Also in:
bpf, linux-arm-kernel, linux-hardening, linux-kbuild, linux-pci, lkml
Subsystem:
bpf [core], bpf [general] (safe dynamic programs and tools), the rest · Maintainers:
Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, Linus Torvalds
Revision v3 of 6 in this series; 1 review trailer.
Revisions (6)
BPF dispatcher functions are patched at runtime to perform direct instead of indirect calls. Disable CFI for the dispatcher functions to avoid conflicts. Signed-off-by: Sami Tolvanen <samitolvanen@google.com> Reviewed-by: Kees Cook <redacted> --- include/linux/bpf.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index cccaef1088ea..9acdca574527 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h@@ -635,7 +635,7 @@ struct bpf_dispatcher { struct bpf_ksym ksym; }; -static __always_inline unsigned int bpf_dispatcher_nop_func( +static __always_inline __nocfi unsigned int bpf_dispatcher_nop_func( const void *ctx, const struct bpf_insn *insnsi, unsigned int (*bpf_func)(const void *,
@@ -663,7 +663,7 @@ void bpf_trampoline_put(struct bpf_trampoline *tr); } #define DEFINE_BPF_DISPATCHER(name) \ - noinline unsigned int bpf_dispatcher_##name##_func( \ + noinline __nocfi unsigned int bpf_dispatcher_##name##_func( \ const void *ctx, \ const struct bpf_insn *insnsi, \ unsigned int (*bpf_func)(const void *, \
--
2.31.0.291.g576ba9dcdaf-goog