From 89b63462765cc0370f22ebec53d3e83cbbb17613 Mon Sep 17 00:00:00 2001 From: Johan Almbladh Date: Fri, 1 Oct 2021 15:03:40 +0200 Subject: [PATCH] bpf/tests: Add zero-extension checks in BPF_ATOMIC tests This patch updates the existing tests of BPF_ATOMIC operations to verify that a 32-bit register operand is properly zero-extended. In particular, it checks the operation on archs that require 32-bit operands to be properly zero-/sign-extended or the result is undefined, e.g. MIPS64. Signed-off-by: Johan Almbladh Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20211001130348.3670534-3-johan.almbladh@anyfinetworks.com --- lib/test_bpf.c | 22 +++++++++++++++++----- 1 file changed, 17 insertions(+), 5 deletions(-) diff --git a/lib/test_bpf.c b/lib/test_bpf.c index a838a6179ca4..f6983ad7b981 100644 --- a/lib/test_bpf.c +++ b/lib/test_bpf.c @@ -7398,15 +7398,20 @@ static struct bpf_test tests[] = { * Individual tests are expanded from template macros for all * combinations of ALU operation, word size and fetching. */ +#define BPF_ATOMIC_POISON(width) ((width) == BPF_W ? (0xbaadf00dULL << 32) : 0) + #define BPF_ATOMIC_OP_TEST1(width, op, logic, old, update, result) \ { \ "BPF_ATOMIC | " #width ", " #op ": Test: " \ #old " " #logic " " #update " = " #result, \ .u.insns_int = { \ - BPF_ALU32_IMM(BPF_MOV, R5, update), \ + BPF_LD_IMM64(R5, (update) | BPF_ATOMIC_POISON(width)), \ BPF_ST_MEM(width, R10, -40, old), \ BPF_ATOMIC_OP(width, op, R10, R5, -40), \ BPF_LDX_MEM(width, R0, R10, -40), \ + BPF_ALU64_REG(BPF_MOV, R1, R0), \ + BPF_ALU64_IMM(BPF_RSH, R1, 32), \ + BPF_ALU64_REG(BPF_OR, R0, R1), \ BPF_EXIT_INSN(), \ }, \ INTERNAL, \ @@ -7420,11 +7425,14 @@ static struct bpf_test tests[] = { #old " " #logic " " #update " = " #result, \ .u.insns_int = { \ BPF_ALU64_REG(BPF_MOV, R1, R10), \ - BPF_ALU32_IMM(BPF_MOV, R0, update), \ + BPF_LD_IMM64(R0, (update) | BPF_ATOMIC_POISON(width)), \ BPF_ST_MEM(BPF_W, R10, -40, old), \ BPF_ATOMIC_OP(width, op, R10, R0, -40), \ BPF_ALU64_REG(BPF_MOV, R0, R10), \ BPF_ALU64_REG(BPF_SUB, R0, R1), \ + BPF_ALU64_REG(BPF_MOV, R1, R0), \ + BPF_ALU64_IMM(BPF_RSH, R1, 32), \ + BPF_ALU64_REG(BPF_OR, R0, R1), \ BPF_EXIT_INSN(), \ }, \ INTERNAL, \ @@ -7438,10 +7446,13 @@ static struct bpf_test tests[] = { #old " " #logic " " #update " = " #result, \ .u.insns_int = { \ BPF_ALU64_REG(BPF_MOV, R0, R10), \ - BPF_ALU32_IMM(BPF_MOV, R1, update), \ + BPF_LD_IMM64(R1, (update) | BPF_ATOMIC_POISON(width)), \ BPF_ST_MEM(width, R10, -40, old), \ BPF_ATOMIC_OP(width, op, R10, R1, -40), \ BPF_ALU64_REG(BPF_SUB, R0, R10), \ + BPF_ALU64_REG(BPF_MOV, R1, R0), \ + BPF_ALU64_IMM(BPF_RSH, R1, 32), \ + BPF_ALU64_REG(BPF_OR, R0, R1), \ BPF_EXIT_INSN(), \ }, \ INTERNAL, \ @@ -7454,10 +7465,10 @@ static struct bpf_test tests[] = { "BPF_ATOMIC | " #width ", " #op ": Test fetch: " \ #old " " #logic " " #update " = " #result, \ .u.insns_int = { \ - BPF_ALU32_IMM(BPF_MOV, R3, update), \ + BPF_LD_IMM64(R3, (update) | BPF_ATOMIC_POISON(width)), \ BPF_ST_MEM(width, R10, -40, old), \ BPF_ATOMIC_OP(width, op, R10, R3, -40), \ - BPF_ALU64_REG(BPF_MOV, R0, R3), \ + BPF_ALU32_REG(BPF_MOV, R0, R3), \ BPF_EXIT_INSN(), \ }, \ INTERNAL, \ @@ -7555,6 +7566,7 @@ static struct bpf_test tests[] = { BPF_ATOMIC_OP_TEST2(BPF_DW, BPF_XCHG, xchg, 0x12, 0xab, 0xab), BPF_ATOMIC_OP_TEST3(BPF_DW, BPF_XCHG, xchg, 0x12, 0xab, 0xab), BPF_ATOMIC_OP_TEST4(BPF_DW, BPF_XCHG, xchg, 0x12, 0xab, 0xab), +#undef BPF_ATOMIC_POISON #undef BPF_ATOMIC_OP_TEST1 #undef BPF_ATOMIC_OP_TEST2 #undef BPF_ATOMIC_OP_TEST3