diff mbox series

[bpf-next,v3,04/17] bpf: Support new unconditional bswap instruction

Message ID 20230720000124.104276-1-yhs@fb.com (mailing list archive)
State Changes Requested
Delegated to: BPF
Headers show
Series bpf: Support new insns from cpu v4 | expand

Checks

Context Check Description
netdev/series_format fail Series longer than 15 patches (and no cover letter)
netdev/tree_selection success Clearly marked for bpf-next, async
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: 1361 this patch: 1361
netdev/cc_maintainers warning 16 maintainers not CCed: tglx@linutronix.de hpa@zytor.com dsahern@kernel.org mingo@redhat.com kpsingh@kernel.org x86@kernel.org john.fastabend@gmail.com sdf@google.com netdev@vger.kernel.org martin.lau@linux.dev song@kernel.org dave.hansen@linux.intel.com davem@davemloft.net jolsa@kernel.org haoluo@google.com bp@alien8.de
netdev/build_clang success Errors and warnings before: 1365 this patch: 1365
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: 1384 this patch: 1384
netdev/checkpatch warning CHECK: No space is necessary after a cast WARNING: labels should not be indented WARNING: line length of 88 exceeds 80 columns
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0
bpf/vmtest-bpf-next-PR success PR summary
bpf/vmtest-bpf-next-VM_Test-1 success Logs for ${{ matrix.test }} on ${{ matrix.arch }} with ${{ matrix.toolchain_full }}
bpf/vmtest-bpf-next-VM_Test-2 success Logs for ShellCheck
bpf/vmtest-bpf-next-VM_Test-3 fail Logs for build for aarch64 with gcc
bpf/vmtest-bpf-next-VM_Test-4 fail Logs for build for s390x with gcc
bpf/vmtest-bpf-next-VM_Test-5 fail Logs for build for x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-6 fail Logs for build for x86_64 with llvm-16
bpf/vmtest-bpf-next-VM_Test-7 success Logs for set-matrix
bpf/vmtest-bpf-next-VM_Test-8 success Logs for veristat

Commit Message

Yonghong Song July 20, 2023, 12:01 a.m. UTC 
The existing 'be' and 'le' insns will do conditional bswap
depends on host endianness. This patch implements
unconditional bswap insns.

Signed-off-by: Yonghong Song <yhs@fb.com>
---
 arch/x86/net/bpf_jit_comp.c |  1 +
 kernel/bpf/core.c           | 14 ++++++++++++++
 kernel/bpf/verifier.c       |  7 +++++--
 3 files changed, 20 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c
index 031ef3c4185d..4942a4c188b9 100644
--- a/arch/x86/net/bpf_jit_comp.c
+++ b/arch/x86/net/bpf_jit_comp.c
@@ -1322,6 +1322,7 @@  static int do_jit(struct bpf_prog *bpf_prog, int *addrs, u8 *image, u8 *rw_image
 			break;
 
 		case BPF_ALU | BPF_END | BPF_FROM_BE:
+		case BPF_ALU64 | BPF_END | BPF_FROM_LE:
 			switch (imm32) {
 			case 16:
 				/* Emit 'ror %ax, 8' to swap lower 2 bytes */
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index c37c454b09eb..ad58697cec4b 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -1524,6 +1524,7 @@  EXPORT_SYMBOL_GPL(__bpf_call_base);
 	INSN_3(ALU64, DIV,  X),			\
 	INSN_3(ALU64, MOD,  X),			\
 	INSN_2(ALU64, NEG),			\
+	INSN_3(ALU64, END, TO_LE),		\
 	/*   Immediate based. */		\
 	INSN_3(ALU64, ADD,  K),			\
 	INSN_3(ALU64, SUB,  K),			\
@@ -1848,6 +1849,19 @@  static u64 ___bpf_prog_run(u64 *regs, const struct bpf_insn *insn)
 			break;
 		}
 		CONT;
+	ALU64_END_TO_LE:
+		switch (IMM) {
+		case 16:
+			DST = (__force u16) __swab16(DST);
+			break;
+		case 32:
+			DST = (__force u32) __swab32(DST);
+			break;
+		case 64:
+			DST = (__force u64) __swab64(DST);
+			break;
+		}
+		CONT;
 
 	/* CALL */
 	JMP_CALL:
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index b9be8706bf48..b305f88c2569 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -3012,8 +3012,10 @@  static bool is_reg64(struct bpf_verifier_env *env, struct bpf_insn *insn,
 		}
 	}
 
+	if (class == BPF_ALU64 && op == BPF_END && (insn->imm == 16 || insn->imm == 32))
+		return false;
+
 	if (class == BPF_ALU64 || class == BPF_JMP ||
-	    /* BPF_END always use BPF_ALU class. */
 	    (class == BPF_ALU && op == BPF_END && insn->imm == 64))
 		return true;
 
@@ -13076,7 +13078,8 @@  static int check_alu_op(struct bpf_verifier_env *env, struct bpf_insn *insn)
 		} else {
 			if (insn->src_reg != BPF_REG_0 || insn->off != 0 ||
 			    (insn->imm != 16 && insn->imm != 32 && insn->imm != 64) ||
-			    BPF_CLASS(insn->code) == BPF_ALU64) {
+			    (BPF_CLASS(insn->code) == BPF_ALU64 &&
+			     BPF_SRC(insn->code) != BPF_TO_LE)) {
 				verbose(env, "BPF_END uses reserved fields\n");
 				return -EINVAL;
 			}