Added test cases to ensure that programs with stack sizes exceeding 512
bytes are restricted in non-JITed mode, and can be executed normally in
JITed mode, even with stack sizes exceeding 512 bytes due to the presence
of may_goto instructions.
Test result:
echo "0" > /proc/sys/net/core/bpf_jit_enable
./test_progs -t verifier_stack_ptr
...
stack size 512 with may_goto with jit:SKIP
stack size 512 with may_goto without jit:OK
...
Summary: 1/27 PASSED, 25 SKIPPED, 0 FAILED
echo "1" > /proc/sys/net/core/bpf_jit_enable
./test_progs -t verifier_stack_ptr
...
stack size 512 with may_goto with jit:OK
stack size 512 with may_goto without jit:SKIP
...
Summary: 1/27 PASSED, 25 SKIPPED, 0 FAILED
Signed-off-by: Jiayuan Chen <mr...@163.com>
---
.../selftests/bpf/progs/verifier_stack_ptr.c | 52 +++++++++++++++++++
1 file changed, 52 insertions(+)
diff --git a/tools/testing/selftests/bpf/progs/verifier_stack_ptr.c
b/tools/testing/selftests/bpf/progs/verifier_stack_ptr.c
index 417c61cd4b19..24aabc6083fd 100644
--- a/tools/testing/selftests/bpf/progs/verifier_stack_ptr.c
+++ b/tools/testing/selftests/bpf/progs/verifier_stack_ptr.c
@@ -481,4 +481,56 @@ l1_%=: r0 = 42;
\
: __clobber_all);
}
+SEC("socket")
+__description("PTR_TO_STACK stack size > 512")
+__failure __msg("invalid write to stack R1 off=-520 size=8")
+__naked void stack_check_size_gt_512(void)
+{
+ asm volatile (" \
+ r1 = r10; \
+ r1 += -520; \
+ r0 = 42; \
+ *(u64*)(r1 + 0) = r0; \
+ exit; \
+" ::: __clobber_all);
+}
+
+#ifdef __BPF_FEATURE_MAY_GOTO
+SEC("socket")
+__description("PTR_TO_STACK stack size 512 with may_goto with jit")
+__load_if_JITed()
+__success __retval(42)
+__naked void stack_check_size_512_with_may_goto_jit(void)
+{
+ asm volatile (" \
+ r1 = r10; \
+ r1 += -512; \
+ r0 = 42; \
+ *(u32*)(r1 + 0) = r0; \
+ may_goto l0_%=; \
+ r2 = 100; \
+ l0_%=: \
+ exit; \
+" ::: __clobber_all);
+}
+
+SEC("socket")
+__description("PTR_TO_STACK stack size 512 with may_goto without jit")
+__load_if_no_JITed()
+__failure __msg("stack size 520(extra 8) is too large")
+__naked void stack_check_size_512_with_may_goto(void)
+{
+ asm volatile (" \
+ r1 = r10; \
+ r1 += -512; \
+ r0 = 42; \
+ *(u32*)(r1 + 0) = r0; \
+ may_goto l0_%=; \
+ r2 = 100; \
+ l0_%=: \
+ exit; \
+" ::: __clobber_all);
+}
+#endif
+
char _license[] SEC("license") = "GPL";
--
2.47.1
