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  2.   patches.suse
  3.   selftests-bpf-Some-more-atomic-tests.patch
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From: Brendan Jackman <jackmanb@google.com>
Date: Fri, 15 Oct 2021 09:33:18 +0000
Subject: selftests/bpf: Some more atomic tests
Patch-mainline: v5.16-rc1
Git-commit: 7960d02dddccc0676d4a1b58e9964718b47388e1
References: git-fixes bsc#1193883 bsc#1194826 CVE-2022-0264
X-Info: dependency of "bpf, selftests: Add test case for atomic fetch on spilled pointer" 180486b430f4e22cc00a478163d942804baae4b5
X-Info: dependency of e523102cb719cbad1673b6aa2a4d5c1fa6f13799 "bpf, selftests: Update test case for atomic cmpxchg on r0 with pointer"


Some new verifier tests that hit some important gaps in the parameter
space for atomic ops.

There are already exhaustive tests for the JIT part in
lib/test_bpf.c, but these exercise the verifier too.

Signed-off-by: Brendan Jackman <jackmanb@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211015093318.1273686-1-jackmanb@google.com
Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
---
 tools/testing/selftests/bpf/verifier/atomic_cmpxchg.c |   38 ++++++++++++
 tools/testing/selftests/bpf/verifier/atomic_fetch.c   |   57 ++++++++++++++++++
 tools/testing/selftests/bpf/verifier/atomic_invalid.c |   25 +++++++
 3 files changed, 120 insertions(+)
 create mode 100644 tools/testing/selftests/bpf/verifier/atomic_fetch.c
 create mode 100644 tools/testing/selftests/bpf/verifier/atomic_invalid.c

--- a/tools/testing/selftests/bpf/verifier/atomic_cmpxchg.c
+++ b/tools/testing/selftests/bpf/verifier/atomic_cmpxchg.c
@@ -119,3 +119,41 @@
 	},
 	.result = ACCEPT,
 },
+{
+	"Dest pointer in r0 - fail",
+	.insns = {
+		/* val = 0; */
+		BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
+		/* r0 = &val */
+		BPF_MOV64_REG(BPF_REG_0, BPF_REG_10),
+		/* r0 = atomic_cmpxchg(&val, r0, 1); */
+		BPF_MOV64_IMM(BPF_REG_1, 1),
+		BPF_ATOMIC_OP(BPF_DW, BPF_CMPXCHG, BPF_REG_10, BPF_REG_1, -8),
+		/* if (r0 != 0) exit(1); */
+		BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 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,
+},
+{
+	"Dest pointer in r0 - succeed",
+	.insns = {
+		/* r0 = &val */
+		BPF_MOV64_REG(BPF_REG_0, BPF_REG_10),
+		/* val = r0; */
+		BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_0, -8),
+		/* r0 = atomic_cmpxchg(&val, r0, 0); */
+		BPF_MOV64_IMM(BPF_REG_1, 0),
+		BPF_ATOMIC_OP(BPF_DW, BPF_CMPXCHG, BPF_REG_10, BPF_REG_1, -8),
+		/* r1 = *r0 */
+		BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0, -8),
+		/* exit(0); */
+		BPF_MOV64_IMM(BPF_REG_0, 0),
+		BPF_EXIT_INSN(),
+	},
+	.result = ACCEPT,
+},
--- /dev/null
+++ b/tools/testing/selftests/bpf/verifier/atomic_fetch.c
@@ -0,0 +1,57 @@
+#define __ATOMIC_FETCH_OP_TEST(src_reg, dst_reg, operand1, op, operand2, expect) \
+	{								\
+		"atomic fetch " #op ", src=" #dst_reg " dst=" #dst_reg,	\
+		.insns = {						\
+			/* u64 val = operan1; */			\
+			BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, operand1),	\
+			/* u64 old = atomic_fetch_add(&val, operand2); */ \
+			BPF_MOV64_REG(dst_reg, BPF_REG_10),		\
+			BPF_MOV64_IMM(src_reg, operand2),		\
+			BPF_ATOMIC_OP(BPF_DW, op,			\
+				      dst_reg, src_reg, -8),		\
+			/* if (old != operand1) exit(1); */		\
+			BPF_JMP_IMM(BPF_JEQ, src_reg, operand1, 2),	\
+			BPF_MOV64_IMM(BPF_REG_0, 1),			\
+			BPF_EXIT_INSN(),				\
+			/* if (val != result) exit (2); */		\
+			BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_10, -8),	\
+			BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, expect, 2),	\
+			BPF_MOV64_IMM(BPF_REG_0, 2),			\
+			BPF_EXIT_INSN(),				\
+			/* exit(0); */					\
+			BPF_MOV64_IMM(BPF_REG_0, 0),			\
+			BPF_EXIT_INSN(),				\
+		},							\
+		.result = ACCEPT,					\
+	}
+__ATOMIC_FETCH_OP_TEST(BPF_REG_1, BPF_REG_2, 1, BPF_ADD | BPF_FETCH, 2, 3),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_0, BPF_REG_1, 1, BPF_ADD | BPF_FETCH, 2, 3),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_1, BPF_REG_0, 1, BPF_ADD | BPF_FETCH, 2, 3),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_2, BPF_REG_3, 1, BPF_ADD | BPF_FETCH, 2, 3),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_4, BPF_REG_5, 1, BPF_ADD | BPF_FETCH, 2, 3),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_9, BPF_REG_8, 1, BPF_ADD | BPF_FETCH, 2, 3),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_1, BPF_REG_2, 0x010, BPF_AND | BPF_FETCH, 0x011, 0x010),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_0, BPF_REG_1, 0x010, BPF_AND | BPF_FETCH, 0x011, 0x010),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_1, BPF_REG_0, 0x010, BPF_AND | BPF_FETCH, 0x011, 0x010),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_2, BPF_REG_3, 0x010, BPF_AND | BPF_FETCH, 0x011, 0x010),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_4, BPF_REG_5, 0x010, BPF_AND | BPF_FETCH, 0x011, 0x010),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_9, BPF_REG_8, 0x010, BPF_AND | BPF_FETCH, 0x011, 0x010),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_1, BPF_REG_2, 0x010, BPF_OR | BPF_FETCH, 0x011, 0x011),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_0, BPF_REG_1, 0x010, BPF_OR | BPF_FETCH, 0x011, 0x011),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_1, BPF_REG_0, 0x010, BPF_OR | BPF_FETCH, 0x011, 0x011),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_2, BPF_REG_3, 0x010, BPF_OR | BPF_FETCH, 0x011, 0x011),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_4, BPF_REG_5, 0x010, BPF_OR | BPF_FETCH, 0x011, 0x011),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_9, BPF_REG_8, 0x010, BPF_OR | BPF_FETCH, 0x011, 0x011),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_1, BPF_REG_2, 0x010, BPF_XOR | BPF_FETCH, 0x011, 0x001),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_0, BPF_REG_1, 0x010, BPF_XOR | BPF_FETCH, 0x011, 0x001),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_1, BPF_REG_0, 0x010, BPF_XOR | BPF_FETCH, 0x011, 0x001),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_2, BPF_REG_3, 0x010, BPF_XOR | BPF_FETCH, 0x011, 0x001),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_4, BPF_REG_5, 0x010, BPF_XOR | BPF_FETCH, 0x011, 0x001),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_9, BPF_REG_8, 0x010, BPF_XOR | BPF_FETCH, 0x011, 0x001),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_1, BPF_REG_2, 0x010, BPF_XCHG, 0x011, 0x011),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_0, BPF_REG_1, 0x010, BPF_XCHG, 0x011, 0x011),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_1, BPF_REG_0, 0x010, BPF_XCHG, 0x011, 0x011),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_2, BPF_REG_3, 0x010, BPF_XCHG, 0x011, 0x011),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_4, BPF_REG_5, 0x010, BPF_XCHG, 0x011, 0x011),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_9, BPF_REG_8, 0x010, BPF_XCHG, 0x011, 0x011),
+#undef __ATOMIC_FETCH_OP_TEST
--- /dev/null
+++ b/tools/testing/selftests/bpf/verifier/atomic_invalid.c
@@ -0,0 +1,25 @@
+#define __INVALID_ATOMIC_ACCESS_TEST(op)					\
+	{								\
+		"atomic " #op " access through non-pointer ",			\
+		.insns = {						\
+			BPF_MOV64_IMM(BPF_REG_0, 1),			\
+			BPF_MOV64_IMM(BPF_REG_1, 0),			\
+			BPF_ATOMIC_OP(BPF_DW, op, BPF_REG_1, BPF_REG_0, -8), \
+			BPF_MOV64_IMM(BPF_REG_0, 0),			\
+			BPF_EXIT_INSN(),				\
+		},							\
+		.result = REJECT,					\
+		.errstr = "R1 invalid mem access 'inv'"			\
+	}
+__INVALID_ATOMIC_ACCESS_TEST(BPF_ADD),
+__INVALID_ATOMIC_ACCESS_TEST(BPF_ADD | BPF_FETCH),
+__INVALID_ATOMIC_ACCESS_TEST(BPF_ADD),
+__INVALID_ATOMIC_ACCESS_TEST(BPF_ADD | BPF_FETCH),
+__INVALID_ATOMIC_ACCESS_TEST(BPF_AND),
+__INVALID_ATOMIC_ACCESS_TEST(BPF_AND | BPF_FETCH),
+__INVALID_ATOMIC_ACCESS_TEST(BPF_OR),
+__INVALID_ATOMIC_ACCESS_TEST(BPF_OR | BPF_FETCH),
+__INVALID_ATOMIC_ACCESS_TEST(BPF_XOR),
+__INVALID_ATOMIC_ACCESS_TEST(BPF_XOR | BPF_FETCH),
+__INVALID_ATOMIC_ACCESS_TEST(BPF_XCHG),
+__INVALID_ATOMIC_ACCESS_TEST(BPF_CMPXCHG),
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