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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /tools/testing/selftests/bpf/verifier/atomic_fetch_add.c
parentInitial commit. (diff)
downloadlinux-upstream.tar.xz
linux-upstream.zip
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'tools/testing/selftests/bpf/verifier/atomic_fetch_add.c')
-rw-r--r--tools/testing/selftests/bpf/verifier/atomic_fetch_add.c106
1 files changed, 106 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/verifier/atomic_fetch_add.c b/tools/testing/selftests/bpf/verifier/atomic_fetch_add.c
new file mode 100644
index 000000000..a91de8cd9
--- /dev/null
+++ b/tools/testing/selftests/bpf/verifier/atomic_fetch_add.c
@@ -0,0 +1,106 @@
+{
+ "BPF_ATOMIC_FETCH_ADD smoketest - 64bit",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ /* Write 3 to stack */
+ BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 3),
+ /* Put a 1 in R1, add it to the 3 on the stack, and load the value back into R1 */
+ BPF_MOV64_IMM(BPF_REG_1, 1),
+ BPF_ATOMIC_OP(BPF_DW, BPF_ADD | BPF_FETCH, BPF_REG_10, BPF_REG_1, -8),
+ /* Check the value we loaded back was 3 */
+ BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 3, 2),
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+ /* Load value from stack */
+ BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_10, -8),
+ /* Check value loaded from stack was 4 */
+ BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 4, 1),
+ BPF_MOV64_IMM(BPF_REG_0, 2),
+ BPF_EXIT_INSN(),
+ },
+ .result = ACCEPT,
+},
+{
+ "BPF_ATOMIC_FETCH_ADD smoketest - 32bit",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ /* Write 3 to stack */
+ BPF_ST_MEM(BPF_W, BPF_REG_10, -4, 3),
+ /* Put a 1 in R1, add it to the 3 on the stack, and load the value back into R1 */
+ BPF_MOV32_IMM(BPF_REG_1, 1),
+ BPF_ATOMIC_OP(BPF_W, BPF_ADD | BPF_FETCH, BPF_REG_10, BPF_REG_1, -4),
+ /* Check the value we loaded back was 3 */
+ BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 3, 2),
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+ /* Load value from stack */
+ BPF_LDX_MEM(BPF_W, BPF_REG_1, BPF_REG_10, -4),
+ /* Check value loaded from stack was 4 */
+ BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 4, 1),
+ BPF_MOV64_IMM(BPF_REG_0, 2),
+ BPF_EXIT_INSN(),
+ },
+ .result = ACCEPT,
+},
+{
+ "Can't use ATM_FETCH_ADD on frame pointer",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 3),
+ BPF_ATOMIC_OP(BPF_DW, BPF_ADD | BPF_FETCH, BPF_REG_10, BPF_REG_10, -8),
+ BPF_EXIT_INSN(),
+ },
+ .result = REJECT,
+ .errstr_unpriv = "R10 leaks addr into mem",
+ .errstr = "frame pointer is read only",
+},
+{
+ "Can't use ATM_FETCH_ADD on uninit src reg",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 3),
+ BPF_ATOMIC_OP(BPF_DW, BPF_ADD | BPF_FETCH, BPF_REG_10, BPF_REG_2, -8),
+ BPF_EXIT_INSN(),
+ },
+ .result = REJECT,
+ /* It happens that the address leak check is first, but it would also be
+ * complain about the fact that we're trying to modify R10.
+ */
+ .errstr = "!read_ok",
+},
+{
+ "Can't use ATM_FETCH_ADD on uninit dst reg",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_ATOMIC_OP(BPF_DW, BPF_ADD | BPF_FETCH, BPF_REG_2, BPF_REG_0, -8),
+ BPF_EXIT_INSN(),
+ },
+ .result = REJECT,
+ /* It happens that the address leak check is first, but it would also be
+ * complain about the fact that we're trying to modify R10.
+ */
+ .errstr = "!read_ok",
+},
+{
+ "Can't use ATM_FETCH_ADD on kernel memory",
+ .insns = {
+ /* This is an fentry prog, context is array of the args of the
+ * kernel function being called. Load first arg into R2.
+ */
+ BPF_LDX_MEM(BPF_DW, BPF_REG_2, BPF_REG_1, 0),
+ /* First arg of bpf_fentry_test7 is a pointer to a struct.
+ * Attempt to modify that struct. Verifier shouldn't let us
+ * because it's kernel memory.
+ */
+ BPF_MOV64_IMM(BPF_REG_3, 1),
+ BPF_ATOMIC_OP(BPF_DW, BPF_ADD | BPF_FETCH, BPF_REG_2, BPF_REG_3, 0),
+ /* Done */
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .prog_type = BPF_PROG_TYPE_TRACING,
+ .expected_attach_type = BPF_TRACE_FENTRY,
+ .kfunc = "bpf_fentry_test7",
+ .result = REJECT,
+ .errstr = "only read is supported",
+},