Merge branch 'bpf-misc-improvements'

Daniel Borkmann says:

====================
This series adds various misc improvements to BPF: detection
of BPF helper definition misconfiguration for mem/size argument
pairs, csum_diff helper also for XDP, various test cases,
removal of the recently added pure_initcall(), restriction
of the jit sysctls to cap_sys_admin for initns, a minor size
improvement for x86 jit in alu ops, output of complexity limit
to verifier log and last but not least having the event output
more flexible with moving to const_size_or_zero type.

Thanks!
====================

Signed-off-by: Alexei Starovoitov <ast@kernel.org>

1 files changed, 30 insertions, 7 deletions

diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c
index 87f214fbe66e..5acee5139e28 100644
--- a/arch/x86/net/bpf_jit_comp.c
+++ b/arch/x86/net/bpf_jit_comp.c
@@ -15,8 +15,6 @@
 #include <asm/set_memory.h>
 #include <linux/bpf.h>
 
-int bpf_jit_enable __read_mostly;
-
 /*
  * assembly code in arch/x86/net/bpf_jit.S
  */
@@ -154,6 +152,11 @@ static bool is_ereg(u32 reg)
 			     BIT(BPF_REG_AX));
 }
 
+static bool is_axreg(u32 reg)
+{
+	return reg == BPF_REG_0;
+}
+
 /* add modifiers if 'reg' maps to x64 registers r8..r15 */
 static u8 add_1mod(u8 byte, u32 reg)
 {
@@ -447,16 +450,36 @@ static int do_jit(struct bpf_prog *bpf_prog, int *addrs, u8 *image,
 			else if (is_ereg(dst_reg))
 				EMIT1(add_1mod(0x40, dst_reg));
 
+			/* b3 holds 'normal' opcode, b2 short form only valid
+			 * in case dst is eax/rax.
+			 */
 			switch (BPF_OP(insn->code)) {
-			case BPF_ADD: b3 = 0xC0; break;
-			case BPF_SUB: b3 = 0xE8; break;
-			case BPF_AND: b3 = 0xE0; break;
-			case BPF_OR: b3 = 0xC8; break;
-			case BPF_XOR: b3 = 0xF0; break;
+			case BPF_ADD:
+				b3 = 0xC0;
+				b2 = 0x05;
+				break;
+			case BPF_SUB:
+				b3 = 0xE8;
+				b2 = 0x2D;
+				break;
+			case BPF_AND:
+				b3 = 0xE0;
+				b2 = 0x25;
+				break;
+			case BPF_OR:
+				b3 = 0xC8;
+				b2 = 0x0D;
+				break;
+			case BPF_XOR:
+				b3 = 0xF0;
+				b2 = 0x35;
+				break;
 			}
 
 			if (is_imm8(imm32))
 				EMIT3(0x83, add_1reg(b3, dst_reg), imm32);
+			else if (is_axreg(dst_reg))
+				EMIT1_off32(b2, imm32);
 			else
 				EMIT2_off32(0x81, add_1reg(b3, dst_reg), imm32);
 			break;