@@ -110,6 +110,10 @@
/* Rd = Rn >> shift; signed */
#define A64_ASR(sf, Rd, Rn, shift) A64_SBFM(sf, Rd, Rn, shift, (sf) ? 63 : 31)
+/* Zero extend */
+#define A64_UXTH(sf, Rd, Rn) A64_UBFM(sf, Rd, Rn, 0, 15)
+#define A64_UXTW(sf, Rd, Rn) A64_UBFM(sf, Rd, Rn, 0, 31)
+
/* Move wide (immediate) */
#define A64_MOVEW(sf, Rd, imm16, shift, type) \
aarch64_insn_gen_movewide(Rd, imm16, shift, \
@@ -289,23 +289,41 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx)
case BPF_ALU | BPF_END | BPF_FROM_BE:
#ifdef CONFIG_CPU_BIG_ENDIAN
if (BPF_SRC(code) == BPF_FROM_BE)
- break;
+ goto emit_bswap_uxt;
#else /* !CONFIG_CPU_BIG_ENDIAN */
if (BPF_SRC(code) == BPF_FROM_LE)
- break;
+ goto emit_bswap_uxt;
#endif
switch (imm) {
case 16:
emit(A64_REV16(is64, dst, dst), ctx);
+ /* zero-extend 16 bits into 64 bits */
+ emit(A64_UXTH(is64, dst, dst), ctx);
break;
case 32:
emit(A64_REV32(is64, dst, dst), ctx);
+ /* upper 32 bits already cleared */
break;
case 64:
emit(A64_REV64(dst, dst), ctx);
break;
}
break;
+emit_bswap_uxt:
+ switch (imm) {
+ case 16:
+ /* zero-extend 16 bits into 64 bits */
+ emit(A64_UXTH(is64, dst, dst), ctx);
+ break;
+ case 32:
+ /* zero-extend 32 bits into 64 bits */
+ emit(A64_UXTW(is64, dst, dst), ctx);
+ break;
+ case 64:
+ /* nop */
+ break;
+ }
+ break;
/* dst = imm */
case BPF_ALU | BPF_MOV | BPF_K:
case BPF_ALU64 | BPF_MOV | BPF_K:
This is a note to let you know that I have just added a patch titled arm64: bpf: fix endianness conversion bugs to the linux-3.19.y-queue branch of the 3.19.y-ckt extended stable tree which can be found at: http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.19.y-queue This patch is scheduled to be released in version 3.19.y-ckt4. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.19.y-ckt tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Kamal ------ From 54c1976eda9ab848a3fac4bc0992983bd5d6af89 Mon Sep 17 00:00:00 2001 From: Xi Wang <xi.wang@gmail.com> Date: Thu, 25 Jun 2015 18:39:15 -0700 Subject: arm64: bpf: fix endianness conversion bugs commit d63903bbc30c7ccad040851dfdb4da12d9a17bcf upstream. Upper bits should be zeroed in endianness conversion: - even when there's no need to change endianness (i.e., BPF_FROM_BE on big endian or BPF_FROM_LE on little endian); - after rev16. This patch fixes such bugs by emitting extra instructions to clear upper bits. Cc: Zi Shen Lim <zlim.lnx@gmail.com> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Fixes: e54bcde3d69d ("arm64: eBPF JIT compiler") Signed-off-by: Xi Wang <xi.wang@gmail.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Kamal Mostafa <kamal@canonical.com> --- arch/arm64/net/bpf_jit.h | 4 ++++ arch/arm64/net/bpf_jit_comp.c | 22 ++++++++++++++++++++-- 2 files changed, 24 insertions(+), 2 deletions(-) -- 1.9.1