Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Daniel Borkmann says:

====================
pull-request: bpf-next 2021-01-16

1) Extend atomic operations to the BPF instruction set along with x86-64 JIT support,
   that is, atomic{,64}_{xchg,cmpxchg,fetch_{add,and,or,xor}}, from Brendan Jackman.

2) Add support for using kernel module global variables (__ksym externs in BPF
   programs) retrieved via module's BTF, from Andrii Nakryiko.

3) Generalize BPF stackmap's buildid retrieval and add support to have buildid
   stored in mmap2 event for perf, from Jiri Olsa.

4) Various fixes for cross-building BPF sefltests out-of-tree which then will
   unblock wider automated testing on ARM hardware, from Jean-Philippe Brucker.

5) Allow to retrieve SOL_SOCKET opts from sock_addr progs, from Daniel Borkmann.

6) Clean up driver's XDP buffer init and split into two helpers to init per-
   descriptor and non-changing fields during processing, from Lorenzo Bianconi.

7) Minor misc improvements to libbpf & bpftool, from Ian Rogers.

* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (41 commits)
  perf: Add build id data in mmap2 event
  bpf: Add size arg to build_id_parse function
  bpf: Move stack_map_get_build_id into lib
  bpf: Document new atomic instructions
  bpf: Add tests for new BPF atomic operations
  bpf: Add bitwise atomic instructions
  bpf: Pull out a macro for interpreting atomic ALU operations
  bpf: Add instructions for atomic_[cmp]xchg
  bpf: Add BPF_FETCH field / create atomic_fetch_add instruction
  bpf: Move BPF_STX reserved field check into BPF_STX verifier code
  bpf: Rename BPF_XADD and prepare to encode other atomics in .imm
  bpf: x86: Factor out a lookup table for some ALU opcodes
  bpf: x86: Factor out emission of REX byte
  bpf: x86: Factor out emission of ModR/M for *(reg + off)
  tools/bpftool: Add -Wall when building BPF programs
  bpf, libbpf: Avoid unused function warning on bpf_tail_call_static
  selftests/bpf: Install btf_dump test cases
  selftests/bpf: Fix installation of urandom_read
  selftests/bpf: Move generated test files to $(TEST_GEN_FILES)
  selftests/bpf: Fix out-of-tree build
  ...
====================

Link: https://lore.kernel.org/r/20210116012922.17823-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 80 insertions, 10 deletions

diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index 261f8692d0d2..5bbd4884ff7a 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -1309,8 +1309,8 @@ EXPORT_SYMBOL_GPL(__bpf_call_base);
 	INSN_3(STX, MEM,  H),			\
 	INSN_3(STX, MEM,  W),			\
 	INSN_3(STX, MEM,  DW),			\
-	INSN_3(STX, XADD, W),			\
-	INSN_3(STX, XADD, DW),			\
+	INSN_3(STX, ATOMIC, W),			\
+	INSN_3(STX, ATOMIC, DW),		\
 	/*   Immediate based. */		\
 	INSN_3(ST, MEM, B),			\
 	INSN_3(ST, MEM, H),			\
@@ -1618,13 +1618,59 @@ out:
 	LDX_PROBE(DW, 8)
 #undef LDX_PROBE
 
-	STX_XADD_W: /* lock xadd *(u32 *)(dst_reg + off16) += src_reg */
-		atomic_add((u32) SRC, (atomic_t *)(unsigned long)
-			   (DST + insn->off));
-		CONT;
-	STX_XADD_DW: /* lock xadd *(u64 *)(dst_reg + off16) += src_reg */
-		atomic64_add((u64) SRC, (atomic64_t *)(unsigned long)
-			     (DST + insn->off));
+#define ATOMIC_ALU_OP(BOP, KOP)						\
+		case BOP:						\
+			if (BPF_SIZE(insn->code) == BPF_W)		\
+				atomic_##KOP((u32) SRC, (atomic_t *)(unsigned long) \
+					     (DST + insn->off));	\
+			else						\
+				atomic64_##KOP((u64) SRC, (atomic64_t *)(unsigned long) \
+					       (DST + insn->off));	\
+			break;						\
+		case BOP | BPF_FETCH:					\
+			if (BPF_SIZE(insn->code) == BPF_W)		\
+				SRC = (u32) atomic_fetch_##KOP(		\
+					(u32) SRC,			\
+					(atomic_t *)(unsigned long) (DST + insn->off)); \
+			else						\
+				SRC = (u64) atomic64_fetch_##KOP(	\
+					(u64) SRC,			\
+					(atomic64_t *)(unsigned long) (DST + insn->off)); \
+			break;
+
+	STX_ATOMIC_DW:
+	STX_ATOMIC_W:
+		switch (IMM) {
+		ATOMIC_ALU_OP(BPF_ADD, add)
+		ATOMIC_ALU_OP(BPF_AND, and)
+		ATOMIC_ALU_OP(BPF_OR, or)
+		ATOMIC_ALU_OP(BPF_XOR, xor)
+#undef ATOMIC_ALU_OP
+
+		case BPF_XCHG:
+			if (BPF_SIZE(insn->code) == BPF_W)
+				SRC = (u32) atomic_xchg(
+					(atomic_t *)(unsigned long) (DST + insn->off),
+					(u32) SRC);
+			else
+				SRC = (u64) atomic64_xchg(
+					(atomic64_t *)(unsigned long) (DST + insn->off),
+					(u64) SRC);
+			break;
+		case BPF_CMPXCHG:
+			if (BPF_SIZE(insn->code) == BPF_W)
+				BPF_R0 = (u32) atomic_cmpxchg(
+					(atomic_t *)(unsigned long) (DST + insn->off),
+					(u32) BPF_R0, (u32) SRC);
+			else
+				BPF_R0 = (u64) atomic64_cmpxchg(
+					(atomic64_t *)(unsigned long) (DST + insn->off),
+					(u64) BPF_R0, (u64) SRC);
+			break;
+
+		default:
+			goto default_label;
+		}
 		CONT;
 
 	default_label:
@@ -1634,7 +1680,8 @@ out:
 		 *
 		 * Note, verifier whitelists all opcodes in bpf_opcode_in_insntable().
 		 */
-		pr_warn("BPF interpreter: unknown opcode %02x\n", insn->code);
+		pr_warn("BPF interpreter: unknown opcode %02x (imm: 0x%x)\n",
+			insn->code, insn->imm);
 		BUG_ON(1);
 		return 0;
 }
@@ -2119,6 +2166,28 @@ static void bpf_free_used_maps(struct bpf_prog_aux *aux)
 	kfree(aux->used_maps);
 }
 
+void __bpf_free_used_btfs(struct bpf_prog_aux *aux,
+			  struct btf_mod_pair *used_btfs, u32 len)
+{
+#ifdef CONFIG_BPF_SYSCALL
+	struct btf_mod_pair *btf_mod;
+	u32 i;
+
+	for (i = 0; i < len; i++) {
+		btf_mod = &used_btfs[i];
+		if (btf_mod->module)
+			module_put(btf_mod->module);
+		btf_put(btf_mod->btf);
+	}
+#endif
+}
+
+static void bpf_free_used_btfs(struct bpf_prog_aux *aux)
+{
+	__bpf_free_used_btfs(aux, aux->used_btfs, aux->used_btf_cnt);
+	kfree(aux->used_btfs);
+}
+
 static void bpf_prog_free_deferred(struct work_struct *work)
 {
 	struct bpf_prog_aux *aux;
@@ -2126,6 +2195,7 @@ static void bpf_prog_free_deferred(struct work_struct *work)
 
 	aux = container_of(work, struct bpf_prog_aux, work);
 	bpf_free_used_maps(aux);
+	bpf_free_used_btfs(aux);
 	if (bpf_prog_is_dev_bound(aux))
 		bpf_prog_offload_destroy(aux->prog);
 #ifdef CONFIG_PERF_EVENTS