diff options
Diffstat (limited to 'tools/testing/selftests/bpf/progs/verifier_reg_equal.c')
-rw-r--r-- | tools/testing/selftests/bpf/progs/verifier_reg_equal.c | 58 |
1 files changed, 58 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/progs/verifier_reg_equal.c b/tools/testing/selftests/bpf/progs/verifier_reg_equal.c new file mode 100644 index 000000000000..dc1d8c30fb0e --- /dev/null +++ b/tools/testing/selftests/bpf/progs/verifier_reg_equal.c @@ -0,0 +1,58 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include <linux/bpf.h> +#include <bpf/bpf_helpers.h> +#include "bpf_misc.h" + +SEC("socket") +__description("check w reg equal if r reg upper32 bits 0") +__success +__naked void subreg_equality_1(void) +{ + asm volatile (" \ + call %[bpf_ktime_get_ns]; \ + *(u64 *)(r10 - 8) = r0; \ + r2 = *(u32 *)(r10 - 8); \ + /* At this point upper 4-bytes of r2 are 0, \ + * thus insn w3 = w2 should propagate reg id, \ + * and w2 < 9 comparison would also propagate \ + * the range for r3. \ + */ \ + w3 = w2; \ + if w2 < 9 goto l0_%=; \ + exit; \ +l0_%=: if r3 < 9 goto l1_%=; \ + /* r1 read is illegal at this point */ \ + r0 -= r1; \ +l1_%=: exit; \ +" : + : __imm(bpf_ktime_get_ns) + : __clobber_all); +} + +SEC("socket") +__description("check w reg not equal if r reg upper32 bits not 0") +__failure __msg("R1 !read_ok") +__naked void subreg_equality_2(void) +{ + asm volatile (" \ + call %[bpf_ktime_get_ns]; \ + r2 = r0; \ + /* Upper 4-bytes of r2 may not be 0, thus insn \ + * w3 = w2 should not propagate reg id, and \ + * w2 < 9 comparison should not propagate \ + * the range for r3 either. \ + */ \ + w3 = w2; \ + if w2 < 9 goto l0_%=; \ + exit; \ +l0_%=: if r3 < 9 goto l1_%=; \ + /* r1 read is illegal at this point */ \ + r0 -= r1; \ +l1_%=: exit; \ +" : + : __imm(bpf_ktime_get_ns) + : __clobber_all); +} + +char _license[] SEC("license") = "GPL"; |