The previous commit improves the precision in scalar(32)_min_max_add,
and scalar(32)_min_max_sub. The improvement in precision occurs in
cases when all outcomes overflow or underflow, respectively. This
commit adds selftests that exercise those cases.
Co-developed-by: Matan Shachnai <m.shachnai@xxxxxxxxxxx>
Signed-off-by: Matan Shachnai <m.shachnai@xxxxxxxxxxx>
Signed-off-by: Harishankar Vishwanathan <harishankar.vishwanathan@xxxxxxxxx>
---
.../selftests/bpf/progs/verifier_bounds.c | 85 +++++++++++++++++++
1 file changed, 85 insertions(+)
diff --git a/tools/testing/selftests/bpf/progs/verifier_bounds.c b/tools/testing/selftests/bpf/progs/verifier_bounds.c
index 30e16153fdf1..20fb0fef5719 100644
--- a/tools/testing/selftests/bpf/progs/verifier_bounds.c
+++ b/tools/testing/selftests/bpf/progs/verifier_bounds.c
@@ -1371,4 +1371,89 @@ __naked void mult_sign_ovf(void)
__imm(bpf_skb_store_bytes)
: __clobber_all);
}
+
+SEC("socket")
+__description("64-bit addition overflow, all outcomes overflow")
+__success __log_level(2)
+__msg("7: (0f) r5 += r3 {{.*}} R5_w=scalar(smin=0x800003d67e960f7d,umin=0x551ee3d67e960f7d,umax=0xc0149fffffffffff,smin32=0xfe960f7d,umin32=0x7e960f7d,var_off=(0x3d67e960f7d; 0xfffffc298169f082))")
+__retval(0)
+__naked void add64_ovf(void)
+{
+ asm volatile (
+ "call %[bpf_get_prandom_u32];"
+ "r3 = r0;"
+ "r4 = 0x950a43d67e960f7d ll;"
+ "r3 |= r4;"
+ "r5 = 0xc014a00000000000 ll;"
+ "r5 += r3;"
+ "r0 = 0;"
+ "exit"
+ :
+ : __imm(bpf_get_prandom_u32)
+ : __clobber_all);
+}
+
+SEC("socket")
+__description("32-bit addition overflow, all outcomes overflow")
+__success __log_level(2)
+__msg("5: (0c) w5 += w3 {{.*}} R5_w=scalar(smin=umin=umin32=0x20130018,smax=umax=umax32=0x8000ffff,smin32=0x80000018,var_off=(0x18; 0xffffffe7))")
+__retval(0)
+__naked void add32_ovf(void)
+{
+ asm volatile (
+ "call %[bpf_get_prandom_u32];"
+ "r3 = r0;"
+ "w4 = 0xa0120018;"
+ "w3 |= w4;"
+ "w5 = 0x80010000;"
+ "w5 += w3;"
+ "r0 = 0;"
+ "exit"
+ :
+ : __imm(bpf_get_prandom_u32)
+ : __clobber_all);
+}
+
+SEC("socket")
+__description("64-bit subtraction overflow, all outcomes underflow")
+__success __log_level(2)
+__msg("6: (1f) r3 -= r1 {{.*}} R3_w=scalar(umin=1,umax=0x8000000000000000)")
+__retval(0)
+__naked void sub64_ovf(void)
+{
+ asm volatile (
+ "call %[bpf_get_prandom_u32];"
+ "r1 = r0;"
+ "r2 = 0x8000000000000000 ll;"
+ "r1 |= r2;"
+ "r3 = 0x0;"
+ "r3 -= r1;"
+ "r0 = 0;"
+ "exit"
+ :
+ : __imm(bpf_get_prandom_u32)
+ : __clobber_all);
+}
+
+SEC("socket")
+__description("32-bit subtraction overflow, all outcomes underflow")
+__success __log_level(2)
+__msg("5: (1c) w3 -= w1 {{.*}} R3_w=scalar(smin=umin=umin32=1,smax=umax=umax32=0x80000000,var_off=(0x0; 0xffffffff))")
+__retval(0)
+__naked void sub32_ovf(void)
+{
+ asm volatile (
+ "call %[bpf_get_prandom_u32];"
+ "r1 = r0;"
+ "w2 = 0x80000000;"
+ "w1 |= w2;"
+ "r3 = 0x0;"
+ "w3 -= w1;"
+ "r0 = 0;"
+ "exit"
+ :
+ : __imm(bpf_get_prandom_u32)
+ : __clobber_all);
+}
+
char _license[] SEC("license") = "GPL";
--
2.45.2
