[PATCH v2 3/4] powerpc/bpf: implement bpf_arch_text_invalidate for bpf_prog_pack
From: Hari Bathini <hbathini@linux.ibm.com>
Date: 2023-03-09 18:02:56
Also in:
bpf
Subsystem:
bpf jit for powerpc (32-bit and 64-bit), bpf [general] (safe dynamic programs and tools), linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Hari Bathini, Christophe Leroy, Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, Madhavan Srinivasan, Michael Ellerman, Linus Torvalds
Implement bpf_arch_text_invalidate and use it to fill unused part of the bpf_prog_pack with trap instructions when a BPF program is freed. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> --- arch/powerpc/net/bpf_jit_comp.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+)
diff --git a/arch/powerpc/net/bpf_jit_comp.c b/arch/powerpc/net/bpf_jit_comp.c
index 0a70319116d1..d1794d9f0154 100644
--- a/arch/powerpc/net/bpf_jit_comp.c
+++ b/arch/powerpc/net/bpf_jit_comp.c@@ -293,3 +293,18 @@ void *bpf_arch_text_copy(void *dst, void *src, size_t len) return ret; } + +int bpf_arch_text_invalidate(void *dst, size_t len) +{ + u32 inst = BREAKPOINT_INSTRUCTION; + int ret = -EINVAL; + + if (WARN_ON_ONCE(core_kernel_text((unsigned long)dst))) + return ret; + + mutex_lock(&text_mutex); + ret = patch_instructions(dst, &inst, true, len); + mutex_unlock(&text_mutex); + + return ret; +}
--
2.39.2