[PATCH v2 7/9] riscv: bpf: Avoid breaking W^X on RV64
From: Jisheng Zhang <hidden>
Date: 2021-03-31 16:34:30
Also in:
bpf, linux-riscv, lkml
Subsystem:
bpf jit for risc-v (64-bit), bpf [general] (safe dynamic programs and tools), risc-v architecture, the rest · Maintainers:
Björn Töpel, Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, Paul Walmsley, Palmer Dabbelt, Albert Ou, Linus Torvalds
From: Jisheng Zhang <jszhang@kernel.org> bpf_jit_binary_lock_ro() in core not only set RO but also set EXEC permission when JIT is done, so no need to allocate RWX from the beginning, and it's not safe. Signed-off-by: Jisheng Zhang <jszhang@kernel.org> --- arch/riscv/net/bpf_jit_comp64.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/riscv/net/bpf_jit_comp64.c b/arch/riscv/net/bpf_jit_comp64.c
index b44ff52f84a6..1c61a82a2856 100644
--- a/arch/riscv/net/bpf_jit_comp64.c
+++ b/arch/riscv/net/bpf_jit_comp64.c@@ -1153,7 +1153,7 @@ void *bpf_jit_alloc_exec(unsigned long size) { return __vmalloc_node_range(size, PAGE_SIZE, BPF_JIT_REGION_START, BPF_JIT_REGION_END, GFP_KERNEL, - PAGE_KERNEL_EXEC, 0, NUMA_NO_NODE, + PAGE_KERNEL, 0, NUMA_NO_NODE, __builtin_return_address(0)); }
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2.31.0