diff mbox series

[v3,bpf-next,05/10] selftests/bpf: validate STACK_ZERO is preserved on subreg spill

Message ID 20231204192601.2672497-6-andrii@kernel.org (mailing list archive)
State Superseded
Delegated to: BPF
Headers show
Series Complete BPF verifier precision tracking support for register spills | expand

Checks

Context Check Description
bpf/vmtest-bpf-next-PR fail PR summary
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for bpf-next, async
netdev/ynl success SINGLE THREAD; Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 8 this patch: 8
netdev/cc_maintainers warning 12 maintainers not CCed: haoluo@google.com jolsa@kernel.org kpsingh@kernel.org martin.lau@linux.dev john.fastabend@gmail.com mykolal@fb.com yonghong.song@linux.dev song@kernel.org shuah@kernel.org sdf@google.com linux-kselftest@vger.kernel.org maxim@isovalent.com
netdev/build_clang success Errors and warnings before: 8 this patch: 8
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 8 this patch: 8
netdev/checkpatch warning CHECK: Lines should not end with a '('
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0
bpf/vmtest-bpf-next-VM_Test-0 success Logs for Lint
bpf/vmtest-bpf-next-VM_Test-1 success Logs for ShellCheck
bpf/vmtest-bpf-next-VM_Test-2 success Logs for Validate matrix.py
bpf/vmtest-bpf-next-VM_Test-3 fail Logs for aarch64-gcc / build / build for aarch64 with gcc
bpf/vmtest-bpf-next-VM_Test-4 success Logs for aarch64-gcc / test
bpf/vmtest-bpf-next-VM_Test-5 success Logs for aarch64-gcc / veristat
bpf/vmtest-bpf-next-VM_Test-6 fail Logs for s390x-gcc / build / build for s390x with gcc
bpf/vmtest-bpf-next-VM_Test-7 success Logs for s390x-gcc / test
bpf/vmtest-bpf-next-VM_Test-8 success Logs for s390x-gcc / veristat
bpf/vmtest-bpf-next-VM_Test-9 success Logs for set-matrix
bpf/vmtest-bpf-next-VM_Test-10 fail Logs for x86_64-gcc / build / build for x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-11 success Logs for x86_64-gcc / test
bpf/vmtest-bpf-next-VM_Test-12 success Logs for x86_64-gcc / veristat
bpf/vmtest-bpf-next-VM_Test-13 fail Logs for x86_64-llvm-16 / build / build for x86_64 with llvm-16
bpf/vmtest-bpf-next-VM_Test-14 success Logs for x86_64-llvm-16 / test
bpf/vmtest-bpf-next-VM_Test-15 success Logs for x86_64-llvm-16 / veristat

Commit Message

Andrii Nakryiko Dec. 4, 2023, 7:25 p.m. UTC 
Add tests validating that STACK_ZERO slots are preserved when slot is
partially overwritten with subregister spill.

Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
---
 .../selftests/bpf/progs/verifier_spill_fill.c | 36 +++++++++++++++++++
 1 file changed, 36 insertions(+)
diff mbox series

Patch

diff --git a/tools/testing/selftests/bpf/progs/verifier_spill_fill.c b/tools/testing/selftests/bpf/progs/verifier_spill_fill.c
index 6115520154e3..899a74ac9093 100644
--- a/tools/testing/selftests/bpf/progs/verifier_spill_fill.c
+++ b/tools/testing/selftests/bpf/progs/verifier_spill_fill.c
@@ -450,4 +450,40 @@  l0_%=:	r1 >>= 16;					\
 	: __clobber_all);
 }
 
+SEC("raw_tp")
+__log_level(2)
+__success
+__msg("fp-8=0m??mmmm")
+__msg("fp-16=00mm??mm")
+__msg("fp-24=00mm???m")
+__naked void spill_subregs_preserve_stack_zero(void)
+{
+	asm volatile (
+		"call %[bpf_get_prandom_u32];"
+
+		/* 32-bit subreg spill with ZERO, MISC, and INVALID */
+		"*(u8 *)(r10 -1) = 0;"  /* ZERO */
+		"*(u8 *)(r10 -2) = r0;" /* MISC */
+		/* fp-3 and fp-4 stay INVALID */
+		"*(u32 *)(r10 -8) = r0;"
+
+		/* 16-bit subreg spill with ZERO, MISC, and INVALID */
+		"*(u16 *)(r10 -10) = 0;"  /* ZERO */
+		"*(u16 *)(r10 -12) = r0;" /* MISC */
+		/* fp-13 and fp-14 stay INVALID */
+		"*(u16 *)(r10 -16) = r0;"
+
+		/* 8-bit subreg spill with ZERO, MISC, and INVALID */
+		"*(u16 *)(r10 -18) = 0;"  /* ZERO */
+		"*(u16 *)(r10 -20) = r0;" /* MISC */
+		/* fp-21, fp-22, and fp-23 stay INVALID */
+		"*(u8 *)(r10 -24) = r0;"
+
+		"r0 = 0;"
+		"exit;"
+	:
+	: __imm(bpf_get_prandom_u32)
+	: __clobber_all);
+}
+
 char _license[] SEC("license") = "GPL";