diff mbox series

[bpf-next,v2,06/15] bpf: Add the assign_scalar_id_before_mov function

Message ID 20240108205209.838365-7-maxtram95@gmail.com (mailing list archive)
State Accepted
Commit 85b6e9d75c8ef207d763d7deea7ececdd513b76b
Delegated to: BPF
Headers show
Series Improvements for tracking scalars in the BPF verifier | expand

Checks

Context Check Description
bpf/vmtest-bpf-next-PR success PR summary
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for bpf-next
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: 1093 this patch: 1093
netdev/cc_maintainers success CCed 0 of 0 maintainers
netdev/build_clang success Errors and warnings before: 1109 this patch: 1109
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: 1120 this patch: 1120
netdev/checkpatch warning WARNING: Too many leading tabs - consider code refactoring WARNING: line length of 82 exceeds 80 columns WARNING: line length of 98 exceeds 80 columns
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-6 success Logs for aarch64-gcc / test (test_maps, false, 360) / test_maps on aarch64 with gcc
bpf/vmtest-bpf-next-VM_Test-9 success Logs for aarch64-gcc / test (test_verifier, false, 360) / test_verifier on aarch64 with gcc
bpf/vmtest-bpf-next-VM_Test-16 success Logs for x86_64-llvm-17 / build / build for x86_64 with llvm-17
bpf/vmtest-bpf-next-VM_Test-14 success Logs for x86_64-gcc / build / build for x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-11 success Logs for s390x-gcc / build / build for s390x with gcc
bpf/vmtest-bpf-next-VM_Test-17 success Logs for s390x-gcc / veristat
bpf/vmtest-bpf-next-VM_Test-18 success Logs for set-matrix
bpf/vmtest-bpf-next-VM_Test-19 success Logs for x86_64-gcc / build / build for x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-20 success Logs for x86_64-gcc / build-release
bpf/vmtest-bpf-next-VM_Test-28 success Logs for x86_64-llvm-17 / build / build for x86_64 with llvm-17
bpf/vmtest-bpf-next-VM_Test-34 success Logs for x86_64-llvm-17 / veristat
bpf/vmtest-bpf-next-VM_Test-35 success Logs for x86_64-llvm-18 / build / build for x86_64 with llvm-18
bpf/vmtest-bpf-next-VM_Test-36 success Logs for x86_64-llvm-18 / build-release / build for x86_64 with llvm-18 and -O2 optimization
bpf/vmtest-bpf-next-VM_Test-42 success Logs for x86_64-llvm-18 / veristat
bpf/vmtest-bpf-next-VM_Test-29 success Logs for x86_64-llvm-17 / build-release / build for x86_64 with llvm-17 and -O2 optimization
bpf/vmtest-bpf-next-VM_Test-21 success Logs for x86_64-gcc / test (test_maps, false, 360) / test_maps on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-24 success Logs for x86_64-gcc / test (test_progs_no_alu32_parallel, true, 30) / test_progs_no_alu32_parallel on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-25 success Logs for x86_64-gcc / test (test_progs_parallel, true, 30) / test_progs_parallel on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-26 success Logs for x86_64-gcc / test (test_verifier, false, 360) / test_verifier on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-27 success Logs for x86_64-gcc / veristat / veristat on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-30 success Logs for x86_64-llvm-17 / test (test_maps, false, 360) / test_maps on x86_64 with llvm-17
bpf/vmtest-bpf-next-VM_Test-33 success Logs for x86_64-llvm-17 / test (test_verifier, false, 360) / test_verifier on x86_64 with llvm-17
bpf/vmtest-bpf-next-VM_Test-37 success Logs for x86_64-llvm-18 / test (test_maps, false, 360) / test_maps on x86_64 with llvm-18
bpf/vmtest-bpf-next-VM_Test-22 success Logs for x86_64-gcc / test (test_progs, false, 360) / test_progs on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-23 success Logs for x86_64-gcc / test (test_progs_no_alu32, false, 360) / test_progs_no_alu32 on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-31 success Logs for x86_64-llvm-17 / test (test_progs, false, 360) / test_progs on x86_64 with llvm-17
bpf/vmtest-bpf-next-VM_Test-32 success Logs for x86_64-llvm-17 / test (test_progs_no_alu32, false, 360) / test_progs_no_alu32 on x86_64 with llvm-17
bpf/vmtest-bpf-next-VM_Test-38 success Logs for x86_64-llvm-18 / test (test_progs, false, 360) / test_progs on x86_64 with llvm-18
bpf/vmtest-bpf-next-VM_Test-39 success Logs for x86_64-llvm-18 / test (test_progs_cpuv4, false, 360) / test_progs_cpuv4 on x86_64 with llvm-18
bpf/vmtest-bpf-next-VM_Test-40 fail Logs for x86_64-llvm-18 / test (test_progs_no_alu32, false, 360) / test_progs_no_alu32 on x86_64 with llvm-18
bpf/vmtest-bpf-next-VM_Test-41 success Logs for x86_64-llvm-18 / test (test_verifier, false, 360) / test_verifier on x86_64 with llvm-18
bpf/vmtest-bpf-next-VM_Test-2 success Logs for Unittests
bpf/vmtest-bpf-next-VM_Test-3 success Logs for Validate matrix.py
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-5 success Logs for aarch64-gcc / build-release
bpf/vmtest-bpf-next-VM_Test-7 success Logs for s390x-gcc / build-release
bpf/vmtest-bpf-next-VM_Test-8 success Logs for set-matrix
bpf/vmtest-bpf-next-VM_Test-4 success Logs for aarch64-gcc / build / build for aarch64 with gcc
bpf/vmtest-bpf-next-VM_Test-10 success Logs for aarch64-gcc / veristat
bpf/vmtest-bpf-next-VM_Test-12 success Logs for s390x-gcc / build-release
bpf/vmtest-bpf-next-VM_Test-13 success Logs for set-matrix
bpf/vmtest-bpf-next-VM_Test-15 success Logs for x86_64-gcc / build-release

Commit Message

Maxim Mikityanskiy Jan. 8, 2024, 8:52 p.m. UTC 
From: Maxim Mikityanskiy <maxim@isovalent.com>

Extract the common code that generates a register ID for src_reg before
MOV if needed into a new function. This function will also be used in
a following commit.

Signed-off-by: Maxim Mikityanskiy <maxim@isovalent.com>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
---
 kernel/bpf/verifier.c | 33 +++++++++++++++++++--------------
 1 file changed, 19 insertions(+), 14 deletions(-)
diff mbox series

Patch

diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index bc565f445410..e3eff2becd64 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -4403,6 +4403,18 @@  static bool __is_pointer_value(bool allow_ptr_leaks,
 	return reg->type != SCALAR_VALUE;
 }
 
+static void assign_scalar_id_before_mov(struct bpf_verifier_env *env,
+					struct bpf_reg_state *src_reg)
+{
+	if (src_reg->type == SCALAR_VALUE && !src_reg->id &&
+	    !tnum_is_const(src_reg->var_off))
+		/* Ensure that src_reg has a valid ID that will be copied to
+		 * dst_reg and then will be used by find_equal_scalars() to
+		 * propagate min/max range.
+		 */
+		src_reg->id = ++env->id_gen;
+}
+
 /* Copy src state preserving dst->parent and dst->live fields */
 static void copy_register_state(struct bpf_reg_state *dst, const struct bpf_reg_state *src)
 {
@@ -13901,20 +13913,13 @@  static int check_alu_op(struct bpf_verifier_env *env, struct bpf_insn *insn)
 		if (BPF_SRC(insn->code) == BPF_X) {
 			struct bpf_reg_state *src_reg = regs + insn->src_reg;
 			struct bpf_reg_state *dst_reg = regs + insn->dst_reg;
-			bool need_id = src_reg->type == SCALAR_VALUE && !src_reg->id &&
-				       !tnum_is_const(src_reg->var_off);
 
 			if (BPF_CLASS(insn->code) == BPF_ALU64) {
 				if (insn->off == 0) {
 					/* case: R1 = R2
 					 * copy register state to dest reg
 					 */
-					if (need_id)
-						/* Assign src and dst registers the same ID
-						 * that will be used by find_equal_scalars()
-						 * to propagate min/max range.
-						 */
-						src_reg->id = ++env->id_gen;
+					assign_scalar_id_before_mov(env, src_reg);
 					copy_register_state(dst_reg, src_reg);
 					dst_reg->live |= REG_LIVE_WRITTEN;
 					dst_reg->subreg_def = DEF_NOT_SUBREG;
@@ -13929,8 +13934,8 @@  static int check_alu_op(struct bpf_verifier_env *env, struct bpf_insn *insn)
 						bool no_sext;
 
 						no_sext = src_reg->umax_value < (1ULL << (insn->off - 1));
-						if (no_sext && need_id)
-							src_reg->id = ++env->id_gen;
+						if (no_sext)
+							assign_scalar_id_before_mov(env, src_reg);
 						copy_register_state(dst_reg, src_reg);
 						if (!no_sext)
 							dst_reg->id = 0;
@@ -13952,8 +13957,8 @@  static int check_alu_op(struct bpf_verifier_env *env, struct bpf_insn *insn)
 					if (insn->off == 0) {
 						bool is_src_reg_u32 = src_reg->umax_value <= U32_MAX;
 
-						if (is_src_reg_u32 && need_id)
-							src_reg->id = ++env->id_gen;
+						if (is_src_reg_u32)
+							assign_scalar_id_before_mov(env, src_reg);
 						copy_register_state(dst_reg, src_reg);
 						/* Make sure ID is cleared if src_reg is not in u32
 						 * range otherwise dst_reg min/max could be incorrectly
@@ -13967,8 +13972,8 @@  static int check_alu_op(struct bpf_verifier_env *env, struct bpf_insn *insn)
 						/* case: W1 = (s8, s16)W2 */
 						bool no_sext = src_reg->umax_value < (1ULL << (insn->off - 1));
 
-						if (no_sext && need_id)
-							src_reg->id = ++env->id_gen;
+						if (no_sext)
+							assign_scalar_id_before_mov(env, src_reg);
 						copy_register_state(dst_reg, src_reg);
 						if (!no_sext)
 							dst_reg->id = 0;