1 files changed, 77 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/verifier/atomic_xor.c b/tools/testing/selftests/bpf/verifier/atomic_xor.c
new file mode 100644
index 000000000000..74e8fb46694b
--- /dev/null
+++ b/tools/testing/selftests/bpf/verifier/atomic_xor.c
@@ -0,0 +1,77 @@
+{
+	"BPF_ATOMIC XOR without fetch",
+	.insns = {
+		/* val = 0x110; */
+		BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0x110),
+		/* atomic_xor(&val, 0x011); */
+		BPF_MOV64_IMM(BPF_REG_1, 0x011),
+		BPF_ATOMIC_OP(BPF_DW, BPF_XOR, BPF_REG_10, BPF_REG_1, -8),
+		/* if (val != 0x101) exit(2); */
+		BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_10, -8),
+		BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0x101, 2),
+		BPF_MOV64_IMM(BPF_REG_0, 2),
+		BPF_EXIT_INSN(),
+		/* r1 should not be clobbered, no BPF_FETCH flag */
+		BPF_MOV64_IMM(BPF_REG_0, 0),
+		BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 0x011, 1),
+		BPF_MOV64_IMM(BPF_REG_0, 1),
+		BPF_EXIT_INSN(),
+	},
+	.result = ACCEPT,
+},
+{
+	"BPF_ATOMIC XOR with fetch",
+	.insns = {
+		BPF_MOV64_IMM(BPF_REG_0, 123),
+		/* val = 0x110; */
+		BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0x110),
+		/* old = atomic_fetch_xor(&val, 0x011); */
+		BPF_MOV64_IMM(BPF_REG_1, 0x011),
+		BPF_ATOMIC_OP(BPF_DW, BPF_XOR | BPF_FETCH, BPF_REG_10, BPF_REG_1, -8),
+		/* if (old != 0x110) exit(3); */
+		BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 0x110, 2),
+		BPF_MOV64_IMM(BPF_REG_0, 3),
+		BPF_EXIT_INSN(),
+		/* if (val != 0x101) exit(2); */
+		BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_10, -8),
+		BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 0x101, 2),
+		BPF_MOV64_IMM(BPF_REG_1, 2),
+		BPF_EXIT_INSN(),
+		/* Check R0 wasn't clobbered (fxor fear of x86 JIT bug) */
+		BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 123, 2),
+		BPF_MOV64_IMM(BPF_REG_0, 1),
+		BPF_EXIT_INSN(),
+		/* exit(0); */
+		BPF_MOV64_IMM(BPF_REG_0, 0),
+		BPF_EXIT_INSN(),
+	},
+	.result = ACCEPT,
+},
+{
+	"BPF_ATOMIC XOR with fetch 32bit",
+	.insns = {
+		/* r0 = (s64) -1 */
+		BPF_MOV64_IMM(BPF_REG_0, 0),
+		BPF_ALU64_IMM(BPF_SUB, BPF_REG_0, 1),
+		/* val = 0x110; */
+		BPF_ST_MEM(BPF_W, BPF_REG_10, -4, 0x110),
+		/* old = atomic_fetch_xor(&val, 0x011); */
+		BPF_MOV32_IMM(BPF_REG_1, 0x011),
+		BPF_ATOMIC_OP(BPF_W, BPF_XOR | BPF_FETCH, BPF_REG_10, BPF_REG_1, -4),
+		/* if (old != 0x110) exit(3); */
+		BPF_JMP32_IMM(BPF_JEQ, BPF_REG_1, 0x110, 2),
+		BPF_MOV32_IMM(BPF_REG_0, 3),
+		BPF_EXIT_INSN(),
+		/* if (val != 0x101) exit(2); */
+		BPF_LDX_MEM(BPF_W, BPF_REG_1, BPF_REG_10, -4),
+		BPF_JMP32_IMM(BPF_JEQ, BPF_REG_1, 0x101, 2),
+		BPF_MOV32_IMM(BPF_REG_1, 2),
+		BPF_EXIT_INSN(),
+		/* Check R0 wasn't clobbered (fxor fear of x86 JIT bug)
+		 * It should be -1 so add 1 to get exit code.
+		 */
+		BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, 1),
+		BPF_EXIT_INSN(),
+	},
+	.result = ACCEPT,
+},