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

Daniel Borkmann says:

====================
pull-request: bpf 2021-12-16

We've added 15 non-merge commits during the last 7 day(s) which contain
a total of 12 files changed, 434 insertions(+), 30 deletions(-).

The main changes are:

1) Fix incorrect verifier state pruning behavior for <8B register spill/fill,
   from Paul Chaignon.

2) Fix x86-64 JIT's extable handling for fentry/fexit when return pointer
   is an ERR_PTR(), from Alexei Starovoitov.

3) Fix 3 different possibilities that BPF verifier missed where unprivileged
   could leak kernel addresses, from Daniel Borkmann.

4) Fix xsk's poll behavior under need_wakeup flag, from Magnus Karlsson.

5) Fix an oob-write in test_verifier due to a missed MAX_NR_MAPS bump,
   from Kumar Kartikeya Dwivedi.

6) Fix a race in test_btf_skc_cls_ingress selftest, from Martin KaFai Lau.

* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
  bpf, selftests: Fix racing issue in btf_skc_cls_ingress test
  selftest/bpf: Add a test that reads various addresses.
  bpf: Fix extable address check.
  bpf: Fix extable fixup offset.
  bpf, selftests: Add test case trying to taint map value pointer
  bpf: Make 32->64 bounds propagation slightly more robust
  bpf: Fix signed bounds propagation after mov32
  bpf, selftests: Update test case for atomic cmpxchg on r0 with pointer
  bpf: Fix kernel address leakage in atomic cmpxchg's r0 aux reg
  bpf, selftests: Add test case for atomic fetch on spilled pointer
  bpf: Fix kernel address leakage in atomic fetch
  selftests/bpf: Fix OOB write in test_verifier
  xsk: Do not sleep in poll() when need_wakeup set
  selftests/bpf: Tests for state pruning with u32 spill/fill
  bpf: Fix incorrect state pruning for <8B spill/fill
====================

Link: https://lore.kernel.org/r/20211216210005.13815-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 71 insertions, 0 deletions

diff --git a/tools/testing/selftests/bpf/verifier/search_pruning.c b/tools/testing/selftests/bpf/verifier/search_pruning.c
index 7e50cb80873a..682519769fe3 100644
--- a/tools/testing/selftests/bpf/verifier/search_pruning.c
+++ b/tools/testing/selftests/bpf/verifier/search_pruning.c
@@ -133,6 +133,77 @@
 	.prog_type = BPF_PROG_TYPE_TRACEPOINT,
 },
 {
+	"precision tracking for u32 spill/fill",
+	.insns = {
+		BPF_MOV64_REG(BPF_REG_7, BPF_REG_1),
+		BPF_EMIT_CALL(BPF_FUNC_get_prandom_u32),
+		BPF_MOV32_IMM(BPF_REG_6, 32),
+		BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 1),
+		BPF_MOV32_IMM(BPF_REG_6, 4),
+		/* Additional insns to introduce a pruning point. */
+		BPF_EMIT_CALL(BPF_FUNC_get_prandom_u32),
+		BPF_MOV64_IMM(BPF_REG_3, 0),
+		BPF_MOV64_IMM(BPF_REG_3, 0),
+		BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 1),
+		BPF_MOV64_IMM(BPF_REG_3, 0),
+		/* u32 spill/fill */
+		BPF_STX_MEM(BPF_W, BPF_REG_10, BPF_REG_6, -8),
+		BPF_LDX_MEM(BPF_W, BPF_REG_8, BPF_REG_10, -8),
+		/* out-of-bound map value access for r6=32 */
+		BPF_ST_MEM(BPF_DW, BPF_REG_10, -16, 0),
+		BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
+		BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -16),
+		BPF_LD_MAP_FD(BPF_REG_1, 0),
+		BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
+		BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2),
+		BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_8),
+		BPF_LDX_MEM(BPF_W, BPF_REG_1, BPF_REG_0, 0),
+		BPF_MOV64_IMM(BPF_REG_0, 0),
+		BPF_EXIT_INSN(),
+	},
+	.fixup_map_hash_8b = { 15 },
+	.result = REJECT,
+	.errstr = "R0 min value is outside of the allowed memory range",
+	.prog_type = BPF_PROG_TYPE_TRACEPOINT,
+},
+{
+	"precision tracking for u32 spills, u64 fill",
+	.insns = {
+		BPF_EMIT_CALL(BPF_FUNC_get_prandom_u32),
+		BPF_MOV64_REG(BPF_REG_6, BPF_REG_0),
+		BPF_MOV32_IMM(BPF_REG_7, 0xffffffff),
+		/* Additional insns to introduce a pruning point. */
+		BPF_MOV64_IMM(BPF_REG_3, 1),
+		BPF_MOV64_IMM(BPF_REG_3, 1),
+		BPF_MOV64_IMM(BPF_REG_3, 1),
+		BPF_MOV64_IMM(BPF_REG_3, 1),
+		BPF_EMIT_CALL(BPF_FUNC_get_prandom_u32),
+		BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 1),
+		BPF_MOV64_IMM(BPF_REG_3, 1),
+		BPF_ALU32_IMM(BPF_DIV, BPF_REG_3, 0),
+		/* u32 spills, u64 fill */
+		BPF_STX_MEM(BPF_W, BPF_REG_10, BPF_REG_6, -4),
+		BPF_STX_MEM(BPF_W, BPF_REG_10, BPF_REG_7, -8),
+		BPF_LDX_MEM(BPF_DW, BPF_REG_8, BPF_REG_10, -8),
+		/* if r8 != X goto pc+1  r8 known in fallthrough branch */
+		BPF_JMP_IMM(BPF_JNE, BPF_REG_8, 0xffffffff, 1),
+		BPF_MOV64_IMM(BPF_REG_3, 1),
+		/* if r8 == X goto pc+1  condition always true on first
+		 * traversal, so starts backtracking to mark r8 as requiring
+		 * precision. r7 marked as needing precision. r6 not marked
+		 * since it's not tracked.
+		 */
+		BPF_JMP_IMM(BPF_JEQ, BPF_REG_8, 0xffffffff, 1),
+		/* fails if r8 correctly marked unknown after fill. */
+		BPF_ALU32_IMM(BPF_DIV, BPF_REG_3, 0),
+		BPF_MOV64_IMM(BPF_REG_0, 0),
+		BPF_EXIT_INSN(),
+	},
+	.result = REJECT,
+	.errstr = "div by zero",
+	.prog_type = BPF_PROG_TYPE_TRACEPOINT,
+},
+{
 	"allocated_stack",
 	.insns = {
 		BPF_ALU64_REG(BPF_MOV, BPF_REG_6, BPF_REG_1),