20 files changed, 446 insertions, 138 deletions

diff --git a/arch/arm/net/bpf_jit_32.c b/arch/arm/net/bpf_jit_32.c
index 897634d0a67c..a951276f0547 100644
--- a/arch/arm/net/bpf_jit_32.c
+++ b/arch/arm/net/bpf_jit_32.c
@@ -1602,6 +1602,9 @@ exit:
 		rn = arm_bpf_get_reg32(src_lo, tmp2[1], ctx);
 		emit_ldx_r(dst, rn, off, ctx, BPF_SIZE(code));
 		break;
+	/* speculation barrier */
+	case BPF_ST | BPF_NOSPEC:
+		break;
 	/* ST: *(size *)(dst + off) = imm */
 	case BPF_ST | BPF_MEM | BPF_W:
 	case BPF_ST | BPF_MEM | BPF_H:
diff --git a/arch/arm64/net/bpf_jit_comp.c b/arch/arm64/net/bpf_jit_comp.c
index dccf98a37283..41c23f474ea6 100644
--- a/arch/arm64/net/bpf_jit_comp.c
+++ b/arch/arm64/net/bpf_jit_comp.c
@@ -823,6 +823,19 @@ emit_cond_jmp:
 			return ret;
 		break;
 
+	/* speculation barrier */
+	case BPF_ST | BPF_NOSPEC:
+		/*
+		 * Nothing required here.
+		 *
+		 * In case of arm64, we rely on the firmware mitigation of
+		 * Speculative Store Bypass as controlled via the ssbd kernel
+		 * parameter. Whenever the mitigation is enabled, it works
+		 * for all of the kernel code with no need to provide any
+		 * additional instructions.
+		 */
+		break;
+
 	/* ST: *(size *)(dst + off) = imm */
 	case BPF_ST | BPF_MEM | BPF_W:
 	case BPF_ST | BPF_MEM | BPF_H:
diff --git a/arch/mips/net/ebpf_jit.c b/arch/mips/net/ebpf_jit.c
index 939dd06764bc..3a73e9375712 100644
--- a/arch/mips/net/ebpf_jit.c
+++ b/arch/mips/net/ebpf_jit.c
@@ -1355,6 +1355,9 @@ jeq_common:
 		}
 		break;
 
+	case BPF_ST | BPF_NOSPEC: /* speculation barrier */
+		break;
+
 	case BPF_ST | BPF_B | BPF_MEM:
 	case BPF_ST | BPF_H | BPF_MEM:
 	case BPF_ST | BPF_W | BPF_MEM:
diff --git a/arch/powerpc/net/bpf_jit_comp32.c b/arch/powerpc/net/bpf_jit_comp32.c
index 34bb1583fc0c..beb12cbc8c29 100644
--- a/arch/powerpc/net/bpf_jit_comp32.c
+++ b/arch/powerpc/net/bpf_jit_comp32.c
@@ -738,6 +738,12 @@ int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, struct codegen_context *
 			break;
 
 		/*
+		 * BPF_ST NOSPEC (speculation barrier)
+		 */
+		case BPF_ST | BPF_NOSPEC:
+			break;
+
+		/*
 		 * BPF_ST(X)
 		 */
 		case BPF_STX | BPF_MEM | BPF_B: /* *(u8 *)(dst + off) = src */
diff --git a/arch/powerpc/net/bpf_jit_comp64.c b/arch/powerpc/net/bpf_jit_comp64.c
index de8595880fee..b87a63dba9c8 100644
--- a/arch/powerpc/net/bpf_jit_comp64.c
+++ b/arch/powerpc/net/bpf_jit_comp64.c
@@ -628,6 +628,12 @@ emit_clear:
 			break;
 
 		/*
+		 * BPF_ST NOSPEC (speculation barrier)
+		 */
+		case BPF_ST | BPF_NOSPEC:
+			break;
+
+		/*
 		 * BPF_ST(X)
 		 */
 		case BPF_STX | BPF_MEM | BPF_B: /* *(u8 *)(dst + off) = src */
diff --git a/arch/riscv/net/bpf_jit_comp32.c b/arch/riscv/net/bpf_jit_comp32.c
index 81de865f4c7c..e6497424cbf6 100644
--- a/arch/riscv/net/bpf_jit_comp32.c
+++ b/arch/riscv/net/bpf_jit_comp32.c
@@ -1251,6 +1251,10 @@ int bpf_jit_emit_insn(const struct bpf_insn *insn, struct rv_jit_context *ctx,
 			return -1;
 		break;
 
+	/* speculation barrier */
+	case BPF_ST | BPF_NOSPEC:
+		break;
+
 	case BPF_ST | BPF_MEM | BPF_B:
 	case BPF_ST | BPF_MEM | BPF_H:
 	case BPF_ST | BPF_MEM | BPF_W:
diff --git a/arch/riscv/net/bpf_jit_comp64.c b/arch/riscv/net/bpf_jit_comp64.c
index 87e3bf5b9086..3af4131c22c7 100644
--- a/arch/riscv/net/bpf_jit_comp64.c
+++ b/arch/riscv/net/bpf_jit_comp64.c
@@ -939,6 +939,10 @@ out_be:
 		emit_ld(rd, 0, RV_REG_T1, ctx);
 		break;
 
+	/* speculation barrier */
+	case BPF_ST | BPF_NOSPEC:
+		break;
+
 	/* ST: *(size *)(dst + off) = imm */
 	case BPF_ST | BPF_MEM | BPF_B:
 		emit_imm(RV_REG_T1, imm, ctx);
diff --git a/arch/s390/net/bpf_jit_comp.c b/arch/s390/net/bpf_jit_comp.c
index 2ae419f5115a..88419263a89a 100644
--- a/arch/s390/net/bpf_jit_comp.c
+++ b/arch/s390/net/bpf_jit_comp.c
@@ -1154,6 +1154,11 @@ static noinline int bpf_jit_insn(struct bpf_jit *jit, struct bpf_prog *fp,
 		}
 		break;
 	/*
+	 * BPF_NOSPEC (speculation barrier)
+	 */
+	case BPF_ST | BPF_NOSPEC:
+		break;
+	/*
 	 * BPF_ST(X)
 	 */
 	case BPF_STX | BPF_MEM | BPF_B: /* *(u8 *)(dst + off) = src_reg */
diff --git a/arch/sparc/net/bpf_jit_comp_64.c b/arch/sparc/net/bpf_jit_comp_64.c
index 4b8d3c65d266..9a2f20cbd48b 100644
--- a/arch/sparc/net/bpf_jit_comp_64.c
+++ b/arch/sparc/net/bpf_jit_comp_64.c
@@ -1287,6 +1287,9 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx)
 			return 1;
 		break;
 	}
+	/* speculation barrier */
+	case BPF_ST | BPF_NOSPEC:
+		break;
 	/* ST: *(size *)(dst + off) = imm */
 	case BPF_ST | BPF_MEM | BPF_W:
 	case BPF_ST | BPF_MEM | BPF_H:
diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c
index 4b951458c9fc..16d76f814e9b 100644
--- a/arch/x86/net/bpf_jit_comp.c
+++ b/arch/x86/net/bpf_jit_comp.c
@@ -1219,6 +1219,13 @@ static int do_jit(struct bpf_prog *bpf_prog, int *addrs, u8 *image,
 			}
 			break;
 
+			/* speculation barrier */
+		case BPF_ST | BPF_NOSPEC:
+			if (boot_cpu_has(X86_FEATURE_XMM2))
+				/* Emit 'lfence' */
+				EMIT3(0x0F, 0xAE, 0xE8);
+			break;
+
 			/* ST: *(u8*)(dst_reg + off) = imm */
 		case BPF_ST | BPF_MEM | BPF_B:
 			if (is_ereg(dst_reg))
diff --git a/arch/x86/net/bpf_jit_comp32.c b/arch/x86/net/bpf_jit_comp32.c
index 3da88ded6ee3..3bfda5f502cb 100644
--- a/arch/x86/net/bpf_jit_comp32.c
+++ b/arch/x86/net/bpf_jit_comp32.c
@@ -1886,6 +1886,12 @@ static int do_jit(struct bpf_prog *bpf_prog, int *addrs, u8 *image,
 			i++;
 			break;
 		}
+		/* speculation barrier */
+		case BPF_ST | BPF_NOSPEC:
+			if (boot_cpu_has(X86_FEATURE_XMM2))
+				/* Emit 'lfence' */
+				EMIT3(0x0F, 0xAE, 0xE8);
+			break;
 		/* ST: *(u8*)(dst_reg + off) = imm */
 		case BPF_ST | BPF_MEM | BPF_H:
 		case BPF_ST | BPF_MEM | BPF_B:
diff --git a/include/linux/bpf_types.h b/include/linux/bpf_types.h
index a9db1eae6796..ae3ac3a2018c 100644
--- a/include/linux/bpf_types.h
+++ b/include/linux/bpf_types.h
@@ -134,4 +134,5 @@ BPF_LINK_TYPE(BPF_LINK_TYPE_CGROUP, cgroup)
 BPF_LINK_TYPE(BPF_LINK_TYPE_ITER, iter)
 #ifdef CONFIG_NET
 BPF_LINK_TYPE(BPF_LINK_TYPE_NETNS, netns)
+BPF_LINK_TYPE(BPF_LINK_TYPE_XDP, xdp)
 #endif
diff --git a/include/linux/bpf_verifier.h b/include/linux/bpf_verifier.h
index e774ecc1cd1f..828d08afeee0 100644
--- a/include/linux/bpf_verifier.h
+++ b/include/linux/bpf_verifier.h
@@ -340,8 +340,8 @@ struct bpf_insn_aux_data {
 	};
 	u64 map_key_state; /* constant (32 bit) key tracking for maps */
 	int ctx_field_size; /* the ctx field size for load insn, maybe 0 */
-	int sanitize_stack_off; /* stack slot to be cleared */
 	u32 seen; /* this insn was processed by the verifier at env->pass_cnt */
+	bool sanitize_stack_spill; /* subject to Spectre v4 sanitation */
 	bool zext_dst; /* this insn zero extends dst reg */
 	u8 alu_state; /* used in combination with alu_limit */
 
@@ -414,6 +414,7 @@ struct bpf_verifier_env {
 	u32 used_map_cnt;		/* number of used maps */
 	u32 used_btf_cnt;		/* number of used BTF objects */
 	u32 id_gen;			/* used to generate unique reg IDs */
+	bool explore_alu_limits;
 	bool allow_ptr_leaks;
 	bool allow_uninit_stack;
 	bool allow_ptr_to_map_access;
diff --git a/include/linux/filter.h b/include/linux/filter.h
index 472f97074da0..83b896044e79 100644
--- a/include/linux/filter.h
+++ b/include/linux/filter.h
@@ -73,6 +73,11 @@ struct ctl_table_header;
 /* unused opcode to mark call to interpreter with arguments */
 #define BPF_CALL_ARGS	0xe0
 
+/* unused opcode to mark speculation barrier for mitigating
+ * Speculative Store Bypass
+ */
+#define BPF_NOSPEC	0xc0
+
 /* As per nm, we expose JITed images as text (code) section for
  * kallsyms. That way, tools like perf can find it to match
  * addresses.
@@ -390,6 +395,16 @@ static inline bool insn_is_zext(const struct bpf_insn *insn)
 		.off   = 0,					\
 		.imm   = 0 })
 
+/* Speculation barrier */
+
+#define BPF_ST_NOSPEC()						\
+	((struct bpf_insn) {					\
+		.code  = BPF_ST | BPF_NOSPEC,			\
+		.dst_reg = 0,					\
+		.src_reg = 0,					\
+		.off   = 0,					\
+		.imm   = 0 })
+
 /* Internal classic blocks for direct assignment */
 
 #define __BPF_STMT(CODE, K)					\
diff --git a/include/linux/skmsg.h b/include/linux/skmsg.h
index 96f319099744..14ab0c0bc924 100644
--- a/include/linux/skmsg.h
+++ b/include/linux/skmsg.h
@@ -285,11 +285,45 @@ static inline struct sk_psock *sk_psock(const struct sock *sk)
 	return rcu_dereference_sk_user_data(sk);
 }
 
+static inline void sk_psock_set_state(struct sk_psock *psock,
+				      enum sk_psock_state_bits bit)
+{
+	set_bit(bit, &psock->state);
+}
+
+static inline void sk_psock_clear_state(struct sk_psock *psock,
+					enum sk_psock_state_bits bit)
+{
+	clear_bit(bit, &psock->state);
+}
+
+static inline bool sk_psock_test_state(const struct sk_psock *psock,
+				       enum sk_psock_state_bits bit)
+{
+	return test_bit(bit, &psock->state);
+}
+
+static inline void sock_drop(struct sock *sk, struct sk_buff *skb)
+{
+	sk_drops_add(sk, skb);
+	kfree_skb(skb);
+}
+
+static inline void drop_sk_msg(struct sk_psock *psock, struct sk_msg *msg)
+{
+	if (msg->skb)
+		sock_drop(psock->sk, msg->skb);
+	kfree(msg);
+}
+
 static inline void sk_psock_queue_msg(struct sk_psock *psock,
 				      struct sk_msg *msg)
 {
 	spin_lock_bh(&psock->ingress_lock);
-	list_add_tail(&msg->list, &psock->ingress_msg);
+	if (sk_psock_test_state(psock, SK_PSOCK_TX_ENABLED))
+		list_add_tail(&msg->list, &psock->ingress_msg);
+	else
+		drop_sk_msg(psock, msg);
 	spin_unlock_bh(&psock->ingress_lock);
 }
 
@@ -406,24 +440,6 @@ static inline void sk_psock_restore_proto(struct sock *sk,
 		psock->psock_update_sk_prot(sk, psock, true);
 }
 
-static inline void sk_psock_set_state(struct sk_psock *psock,
-				      enum sk_psock_state_bits bit)
-{
-	set_bit(bit, &psock->state);
-}
-
-static inline void sk_psock_clear_state(struct sk_psock *psock,
-					enum sk_psock_state_bits bit)
-{
-	clear_bit(bit, &psock->state);
-}
-
-static inline bool sk_psock_test_state(const struct sk_psock *psock,
-				       enum sk_psock_state_bits bit)
-{
-	return test_bit(bit, &psock->state);
-}
-
 static inline struct sk_psock *sk_psock_get(struct sock *sk)
 {
 	struct sk_psock *psock;
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index 9b1577498373..b1a5fc04492b 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -32,6 +32,8 @@
 #include <linux/perf_event.h>
 #include <linux/extable.h>
 #include <linux/log2.h>
+
+#include <asm/barrier.h>
 #include <asm/unaligned.h>
 
 /* Registers */
@@ -1377,6 +1379,7 @@ static u64 ___bpf_prog_run(u64 *regs, const struct bpf_insn *insn)
 		/* Non-UAPI available opcodes. */
 		[BPF_JMP | BPF_CALL_ARGS] = &&JMP_CALL_ARGS,
 		[BPF_JMP | BPF_TAIL_CALL] = &&JMP_TAIL_CALL,
+		[BPF_ST  | BPF_NOSPEC] = &&ST_NOSPEC,
 		[BPF_LDX | BPF_PROBE_MEM | BPF_B] = &&LDX_PROBE_MEM_B,
 		[BPF_LDX | BPF_PROBE_MEM | BPF_H] = &&LDX_PROBE_MEM_H,
 		[BPF_LDX | BPF_PROBE_MEM | BPF_W] = &&LDX_PROBE_MEM_W,
@@ -1621,7 +1624,21 @@ out:
 	COND_JMP(s, JSGE, >=)
 	COND_JMP(s, JSLE, <=)
 #undef COND_JMP
-	/* STX and ST and LDX*/
+	/* ST, STX and LDX*/
+	ST_NOSPEC:
+		/* Speculation barrier for mitigating Speculative Store Bypass.
+		 * In case of arm64, we rely on the firmware mitigation as
+		 * controlled via the ssbd kernel parameter. Whenever the
+		 * mitigation is enabled, it works for all of the kernel code
+		 * with no need to provide any additional instructions here.
+		 * In case of x86, we use 'lfence' insn for mitigation. We
+		 * reuse preexisting logic from Spectre v1 mitigation that
+		 * happens to produce the required code on x86 for v4 as well.
+		 */
+#ifdef CONFIG_X86
+		barrier_nospec();
+#endif
+		CONT;
 #define LDST(SIZEOP, SIZE)						\
 	STX_MEM_##SIZEOP:						\
 		*(SIZE *)(unsigned long) (DST + insn->off) = SRC;	\
diff --git a/kernel/bpf/disasm.c b/kernel/bpf/disasm.c
index bbfc6bb79240..ca3cd9aaa6ce 100644
--- a/kernel/bpf/disasm.c
+++ b/kernel/bpf/disasm.c
@@ -206,15 +206,17 @@ void print_bpf_insn(const struct bpf_insn_cbs *cbs,
 			verbose(cbs->private_data, "BUG_%02x\n", insn->code);
 		}
 	} else if (class == BPF_ST) {
-		if (BPF_MODE(insn->code) != BPF_MEM) {
+		if (BPF_MODE(insn->code) == BPF_MEM) {
+			verbose(cbs->private_data, "(%02x) *(%s *)(r%d %+d) = %d\n",
+				insn->code,
+				bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
+				insn->dst_reg,
+				insn->off, insn->imm);
+		} else if (BPF_MODE(insn->code) == 0xc0 /* BPF_NOSPEC, no UAPI */) {
+			verbose(cbs->private_data, "(%02x) nospec\n", insn->code);
+		} else {
 			verbose(cbs->private_data, "BUG_st_%02x\n", insn->code);
-			return;
 		}
-		verbose(cbs->private_data, "(%02x) *(%s *)(r%d %+d) = %d\n",
-			insn->code,
-			bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
-			insn->dst_reg,
-			insn->off, insn->imm);
 	} else if (class == BPF_LDX) {
 		if (BPF_MODE(insn->code) != BPF_MEM) {
 			verbose(cbs->private_data, "BUG_ldx_%02x\n", insn->code);
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 9de3c9c3267c..f9bda5476ea5 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -2610,6 +2610,19 @@ static int check_stack_write_fixed_off(struct bpf_verifier_env *env,
 	cur = env->cur_state->frame[env->cur_state->curframe];
 	if (value_regno >= 0)
 		reg = &cur->regs[value_regno];
+	if (!env->bypass_spec_v4) {
+		bool sanitize = reg && is_spillable_regtype(reg->type);
+
+		for (i = 0; i < size; i++) {
+			if (state->stack[spi].slot_type[i] == STACK_INVALID) {
+				sanitize = true;
+				break;
+			}
+		}
+
+		if (sanitize)
+			env->insn_aux_data[insn_idx].sanitize_stack_spill = true;
+	}
 
 	if (reg && size == BPF_REG_SIZE && register_is_bounded(reg) &&
 	    !register_is_null(reg) && env->bpf_capable) {
@@ -2632,47 +2645,10 @@ static int check_stack_write_fixed_off(struct bpf_verifier_env *env,
 			verbose(env, "invalid size of register spill\n");
 			return -EACCES;
 		}
-
 		if (state != cur && reg->type == PTR_TO_STACK) {
 			verbose(env, "cannot spill pointers to stack into stack frame of the caller\n");
 			return -EINVAL;
 		}
-
-		if (!env->bypass_spec_v4) {
-			bool sanitize = false;
-
-			if (state->stack[spi].slot_type[0] == STACK_SPILL &&
-			    register_is_const(&state->stack[spi].spilled_ptr))
-				sanitize = true;
-			for (i = 0; i < BPF_REG_SIZE; i++)
-				if (state->stack[spi].slot_type[i] == STACK_MISC) {
-					sanitize = true;
-					break;
-				}
-			if (sanitize) {
-				int *poff = &env->insn_aux_data[insn_idx].sanitize_stack_off;
-				int soff = (-spi - 1) * BPF_REG_SIZE;
-
-				/* detected reuse of integer stack slot with a pointer
-				 * which means either llvm is reusing stack slot or
-				 * an attacker is trying to exploit CVE-2018-3639
-				 * (speculative store bypass)
-				 * Have to sanitize that slot with preemptive
-				 * store of zero.
-				 */
-				if (*poff && *poff != soff) {
-					/* disallow programs where single insn stores
-					 * into two different stack slots, since verifier
-					 * cannot sanitize them
-					 */
-					verbose(env,
-						"insn %d cannot access two stack slots fp%d and fp%d",
-						insn_idx, *poff, soff);
-					return -EINVAL;
-				}
-				*poff = soff;
-			}
-		}
 		save_register_state(state, spi, reg);
 	} else {
 		u8 type = STACK_MISC;
@@ -6561,6 +6537,12 @@ static int sanitize_ptr_alu(struct bpf_verifier_env *env,
 		alu_state |= off_is_imm ? BPF_ALU_IMMEDIATE : 0;
 		alu_state |= ptr_is_dst_reg ?
 			     BPF_ALU_SANITIZE_SRC : BPF_ALU_SANITIZE_DST;
+
+		/* Limit pruning on unknown scalars to enable deep search for
+		 * potential masking differences from other program paths.
+		 */
+		if (!off_is_imm)
+			env->explore_alu_limits = true;
 	}
 
 	err = update_alu_sanitation_state(aux, alu_state, alu_limit);
@@ -9936,8 +9918,8 @@ next:
 }
 
 /* Returns true if (rold safe implies rcur safe) */
-static bool regsafe(struct bpf_reg_state *rold, struct bpf_reg_state *rcur,
-		    struct bpf_id_pair *idmap)
+static bool regsafe(struct bpf_verifier_env *env, struct bpf_reg_state *rold,
+		    struct bpf_reg_state *rcur, struct bpf_id_pair *idmap)
 {
 	bool equal;
 
@@ -9963,6 +9945,8 @@ static bool regsafe(struct bpf_reg_state *rold, struct bpf_reg_state *rcur,
 		return false;
 	switch (rold->type) {
 	case SCALAR_VALUE:
+		if (env->explore_alu_limits)
+			return false;
 		if (rcur->type == SCALAR_VALUE) {
 			if (!rold->precise && !rcur->precise)
 				return true;
@@ -10053,9 +10037,8 @@ static bool regsafe(struct bpf_reg_state *rold, struct bpf_reg_state *rcur,
 	return false;
 }
 
-static bool stacksafe(struct bpf_func_state *old,
-		      struct bpf_func_state *cur,
-		      struct bpf_id_pair *idmap)
+static bool stacksafe(struct bpf_verifier_env *env, struct bpf_func_state *old,
+		      struct bpf_func_state *cur, struct bpf_id_pair *idmap)
 {
 	int i, spi;
 
@@ -10100,9 +10083,8 @@ static bool stacksafe(struct bpf_func_state *old,
 			continue;
 		if (old->stack[spi].slot_type[0] != STACK_SPILL)
 			continue;
-		if (!regsafe(&old->stack[spi].spilled_ptr,
-			     &cur->stack[spi].spilled_ptr,
-			     idmap))
+		if (!regsafe(env, &old->stack[spi].spilled_ptr,
+			     &cur->stack[spi].spilled_ptr, idmap))
 			/* when explored and current stack slot are both storing
 			 * spilled registers, check that stored pointers types
 			 * are the same as well.
@@ -10159,10 +10141,11 @@ static bool func_states_equal(struct bpf_verifier_env *env, struct bpf_func_stat
 
 	memset(env->idmap_scratch, 0, sizeof(env->idmap_scratch));
 	for (i = 0; i < MAX_BPF_REG; i++)
-		if (!regsafe(&old->regs[i], &cur->regs[i], env->idmap_scratch))
+		if (!regsafe(env, &old->regs[i], &cur->regs[i],
+			     env->idmap_scratch))
 			return false;
 
-	if (!stacksafe(old, cur, env->idmap_scratch))
+	if (!stacksafe(env, old, cur, env->idmap_scratch))
 		return false;
 
 	if (!refsafe(old, cur))
@@ -11906,35 +11889,33 @@ static int convert_ctx_accesses(struct bpf_verifier_env *env)
 
 	for (i = 0; i < insn_cnt; i++, insn++) {
 		bpf_convert_ctx_access_t convert_ctx_access;
+		bool ctx_access;
 
 		if (insn->code == (BPF_LDX | BPF_MEM | BPF_B) ||
 		    insn->code == (BPF_LDX | BPF_MEM | BPF_H) ||
 		    insn->code == (BPF_LDX | BPF_MEM | BPF_W) ||
-		    insn->code == (BPF_LDX | BPF_MEM | BPF_DW))
+		    insn->code == (BPF_LDX | BPF_MEM | BPF_DW)) {
 			type = BPF_READ;
-		else if (insn->code == (BPF_STX | BPF_MEM | BPF_B) ||
-			 insn->code == (BPF_STX | BPF_MEM | BPF_H) ||
-			 insn->code == (BPF_STX | BPF_MEM | BPF_W) ||
-			 insn->code == (BPF_STX | BPF_MEM | BPF_DW))
+			ctx_access = true;
+		} else if (insn->code == (BPF_STX | BPF_MEM | BPF_B) ||
+			   insn->code == (BPF_STX | BPF_MEM | BPF_H) ||
+			   insn->code == (BPF_STX | BPF_MEM | BPF_W) ||
+			   insn->code == (BPF_STX | BPF_MEM | BPF_DW) ||
+			   insn->code == (BPF_ST | BPF_MEM | BPF_B) ||
+			   insn->code == (BPF_ST | BPF_MEM | BPF_H) ||
+			   insn->code == (BPF_ST | BPF_MEM | BPF_W) ||
+			   insn->code == (BPF_ST | BPF_MEM | BPF_DW)) {
 			type = BPF_WRITE;
-		else
+			ctx_access = BPF_CLASS(insn->code) == BPF_STX;
+		} else {
 			continue;
+		}
 
 		if (type == BPF_WRITE &&
-		    env->insn_aux_data[i + delta].sanitize_stack_off) {
+		    env->insn_aux_data[i + delta].sanitize_stack_spill) {
 			struct bpf_insn patch[] = {
-				/* Sanitize suspicious stack slot with zero.
-				 * There are no memory dependencies for this store,
-				 * since it's only using frame pointer and immediate
-				 * constant of zero
-				 */
-				BPF_ST_MEM(BPF_DW, BPF_REG_FP,
-					   env->insn_aux_data[i + delta].sanitize_stack_off,
-					   0),
-				/* the original STX instruction will immediately
-				 * overwrite the same stack slot with appropriate value
-				 */
 				*insn,
+				BPF_ST_NOSPEC(),
 			};
 
 			cnt = ARRAY_SIZE(patch);
@@ -11948,6 +11929,9 @@ static int convert_ctx_accesses(struct bpf_verifier_env *env)
 			continue;
 		}
 
+		if (!ctx_access)
+			continue;
+
 		switch (env->insn_aux_data[i + delta].ptr_type) {
 		case PTR_TO_CTX:
 			if (!ops->convert_ctx_access)
@@ -12752,37 +12736,6 @@ static void free_states(struct bpf_verifier_env *env)
 	}
 }
 
-/* The verifier is using insn_aux_data[] to store temporary data during
- * verification and to store information for passes that run after the
- * verification like dead code sanitization. do_check_common() for subprogram N
- * may analyze many other subprograms. sanitize_insn_aux_data() clears all
- * temporary data after do_check_common() finds that subprogram N cannot be
- * verified independently. pass_cnt counts the number of times
- * do_check_common() was run and insn->aux->seen tells the pass number
- * insn_aux_data was touched. These variables are compared to clear temporary
- * data from failed pass. For testing and experiments do_check_common() can be
- * run multiple times even when prior attempt to verify is unsuccessful.
- *
- * Note that special handling is needed on !env->bypass_spec_v1 if this is
- * ever called outside of error path with subsequent program rejection.
- */
-static void sanitize_insn_aux_data(struct bpf_verifier_env *env)
-{
-	struct bpf_insn *insn = env->prog->insnsi;
-	struct bpf_insn_aux_data *aux;
-	int i, class;
-
-	for (i = 0; i < env->prog->len; i++) {
-		class = BPF_CLASS(insn[i].code);
-		if (class != BPF_LDX && class != BPF_STX)
-			continue;
-		aux = &env->insn_aux_data[i];
-		if (aux->seen != env->pass_cnt)
-			continue;
-		memset(aux, 0, offsetof(typeof(*aux), orig_idx));
-	}
-}
-
 static int do_check_common(struct bpf_verifier_env *env, int subprog)
 {
 	bool pop_log = !(env->log.level & BPF_LOG_LEVEL2);
@@ -12859,9 +12812,6 @@ out:
 	if (!ret && pop_log)
 		bpf_vlog_reset(&env->log, 0);
 	free_states(env);
-	if (ret)
-		/* clean aux data in case subprog was rejected */
-		sanitize_insn_aux_data(env);
 	return ret;
 }
 
diff --git a/net/core/skmsg.c b/net/core/skmsg.c
index 15d71288e741..2d6249b28928 100644
--- a/net/core/skmsg.c
+++ b/net/core/skmsg.c
@@ -584,29 +584,42 @@ static int sk_psock_handle_skb(struct sk_psock *psock, struct sk_buff *skb,
 	return sk_psock_skb_ingress(psock, skb);
 }
 
-static void sock_drop(struct sock *sk, struct sk_buff *skb)
+static void sk_psock_skb_state(struct sk_psock *psock,
+			       struct sk_psock_work_state *state,
+			       struct sk_buff *skb,
+			       int len, int off)
 {
-	sk_drops_add(sk, skb);
-	kfree_skb(skb);
+	spin_lock_bh(&psock->ingress_lock);
+	if (sk_psock_test_state(psock, SK_PSOCK_TX_ENABLED)) {
+		state->skb = skb;
+		state->len = len;
+		state->off = off;
+	} else {
+		sock_drop(psock->sk, skb);
+	}
+	spin_unlock_bh(&psock->ingress_lock);
 }
 
 static void sk_psock_backlog(struct work_struct *work)
 {
 	struct sk_psock *psock = container_of(work, struct sk_psock, work);
 	struct sk_psock_work_state *state = &psock->work_state;
-	struct sk_buff *skb;
+	struct sk_buff *skb = NULL;
 	bool ingress;
 	u32 len, off;
 	int ret;
 
 	mutex_lock(&psock->work_mutex);
-	if (state->skb) {
+	if (unlikely(state->skb)) {
+		spin_lock_bh(&psock->ingress_lock);
 		skb = state->skb;
 		len = state->len;
 		off = state->off;
 		state->skb = NULL;
-		goto start;
+		spin_unlock_bh(&psock->ingress_lock);
 	}
+	if (skb)
+		goto start;
 
 	while ((skb = skb_dequeue(&psock->ingress_skb))) {
 		len = skb->len;
@@ -621,9 +634,8 @@ start:
 							  len, ingress);
 			if (ret <= 0) {
 				if (ret == -EAGAIN) {
-					state->skb = skb;
-					state->len = len;
-					state->off = off;
+					sk_psock_skb_state(psock, state, skb,
+							   len, off);
 					goto end;
 				}
 				/* Hard errors break pipe and stop xmit. */
@@ -722,6 +734,11 @@ static void __sk_psock_zap_ingress(struct sk_psock *psock)
 		skb_bpf_redirect_clear(skb);
 		sock_drop(psock->sk, skb);
 	}
+	kfree_skb(psock->work_state.skb);
+	/* We null the skb here to ensure that calls to sk_psock_backlog
+	 * do not pick up the free'd skb.
+	 */
+	psock->work_state.skb = NULL;
 	__sk_psock_purge_ingress_msg(psock);
 }
 
@@ -773,8 +790,6 @@ static void sk_psock_destroy(struct work_struct *work)
 
 void sk_psock_drop(struct sock *sk, struct sk_psock *psock)
 {
-	sk_psock_stop(psock, false);
-
 	write_lock_bh(&sk->sk_callback_lock);
 	sk_psock_restore_proto(sk, psock);
 	rcu_assign_sk_user_data(sk, NULL);
@@ -784,6 +799,8 @@ void sk_psock_drop(struct sock *sk, struct sk_psock *psock)
 		sk_psock_stop_verdict(sk, psock);
 	write_unlock_bh(&sk->sk_callback_lock);
 
+	sk_psock_stop(psock, false);
+
 	INIT_RCU_WORK(&psock->rwork, sk_psock_destroy);
 	queue_rcu_work(system_wq, &psock->rwork);
 }
diff --git a/tools/testing/selftests/bpf/verifier/value_ptr_arith.c b/tools/testing/selftests/bpf/verifier/value_ptr_arith.c
index a3e593ddfafc..2debba4e8a3a 100644
--- a/tools/testing/selftests/bpf/verifier/value_ptr_arith.c
+++ b/tools/testing/selftests/bpf/verifier/value_ptr_arith.c
@@ -1,4 +1,233 @@
 {
+	"map access: known scalar += value_ptr unknown vs const",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1,
+		    offsetof(struct __sk_buff, len)),
+	BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
+	BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
+	BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 1, 3),
+	BPF_LD_MAP_FD(BPF_REG_1, 0),
+	BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 1, 2),
+	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, 9),
+	BPF_LDX_MEM(BPF_B, BPF_REG_4, BPF_REG_0, 0),
+	BPF_JMP_IMM(BPF_JEQ, BPF_REG_4, 1, 4),
+	BPF_MOV64_IMM(BPF_REG_1, 6),
+	BPF_ALU64_IMM(BPF_NEG, BPF_REG_1, 0),
+	BPF_ALU64_IMM(BPF_AND, BPF_REG_1, 0x7),
+	BPF_JMP_IMM(BPF_JA, 0, 0, 1),
+	BPF_MOV64_IMM(BPF_REG_1, 3),
+	BPF_ALU64_REG(BPF_ADD, BPF_REG_1, BPF_REG_0),
+	BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1, 0),
+	BPF_MOV64_IMM(BPF_REG_0, 1),
+	BPF_EXIT_INSN(),
+	},
+	.fixup_map_hash_16b = { 5 },
+	.fixup_map_array_48b = { 8 },
+	.result_unpriv = REJECT,
+	.errstr_unpriv = "R1 tried to add from different maps, paths or scalars",
+	.result = ACCEPT,
+	.retval = 1,
+},
+{
+	"map access: known scalar += value_ptr const vs unknown",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1,
+		    offsetof(struct __sk_buff, len)),
+	BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
+	BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
+	BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 1, 3),
+	BPF_LD_MAP_FD(BPF_REG_1, 0),
+	BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 1, 2),
+	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, 9),
+	BPF_LDX_MEM(BPF_B, BPF_REG_4, BPF_REG_0, 0),
+	BPF_JMP_IMM(BPF_JEQ, BPF_REG_4, 1, 2),
+	BPF_MOV64_IMM(BPF_REG_1, 3),
+	BPF_JMP_IMM(BPF_JA, 0, 0, 3),
+	BPF_MOV64_IMM(BPF_REG_1, 6),
+	BPF_ALU64_IMM(BPF_NEG, BPF_REG_1, 0),
+	BPF_ALU64_IMM(BPF_AND, BPF_REG_1, 0x7),
+	BPF_ALU64_REG(BPF_ADD, BPF_REG_1, BPF_REG_0),
+	BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1, 0),
+	BPF_MOV64_IMM(BPF_REG_0, 1),
+	BPF_EXIT_INSN(),
+	},
+	.fixup_map_hash_16b = { 5 },
+	.fixup_map_array_48b = { 8 },
+	.result_unpriv = REJECT,
+	.errstr_unpriv = "R1 tried to add from different maps, paths or scalars",
+	.result = ACCEPT,
+	.retval = 1,
+},
+{
+	"map access: known scalar += value_ptr const vs const (ne)",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1,
+		    offsetof(struct __sk_buff, len)),
+	BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
+	BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
+	BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 1, 3),
+	BPF_LD_MAP_FD(BPF_REG_1, 0),
+	BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 1, 2),
+	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, 7),
+	BPF_LDX_MEM(BPF_B, BPF_REG_4, BPF_REG_0, 0),
+	BPF_JMP_IMM(BPF_JEQ, BPF_REG_4, 1, 2),
+	BPF_MOV64_IMM(BPF_REG_1, 3),
+	BPF_JMP_IMM(BPF_JA, 0, 0, 1),
+	BPF_MOV64_IMM(BPF_REG_1, 5),
+	BPF_ALU64_REG(BPF_ADD, BPF_REG_1, BPF_REG_0),
+	BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1, 0),
+	BPF_MOV64_IMM(BPF_REG_0, 1),
+	BPF_EXIT_INSN(),
+	},
+	.fixup_map_hash_16b = { 5 },
+	.fixup_map_array_48b = { 8 },
+	.result_unpriv = REJECT,
+	.errstr_unpriv = "R1 tried to add from different maps, paths or scalars",
+	.result = ACCEPT,
+	.retval = 1,
+},
+{
+	"map access: known scalar += value_ptr const vs const (eq)",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1,
+		    offsetof(struct __sk_buff, len)),
+	BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
+	BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
+	BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 1, 3),
+	BPF_LD_MAP_FD(BPF_REG_1, 0),
+	BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 1, 2),
+	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, 7),
+	BPF_LDX_MEM(BPF_B, BPF_REG_4, BPF_REG_0, 0),
+	BPF_JMP_IMM(BPF_JEQ, BPF_REG_4, 1, 2),
+	BPF_MOV64_IMM(BPF_REG_1, 5),
+	BPF_JMP_IMM(BPF_JA, 0, 0, 1),
+	BPF_MOV64_IMM(BPF_REG_1, 5),
+	BPF_ALU64_REG(BPF_ADD, BPF_REG_1, BPF_REG_0),
+	BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1, 0),
+	BPF_MOV64_IMM(BPF_REG_0, 1),
+	BPF_EXIT_INSN(),
+	},
+	.fixup_map_hash_16b = { 5 },
+	.fixup_map_array_48b = { 8 },
+	.result = ACCEPT,
+	.retval = 1,
+},
+{
+	"map access: known scalar += value_ptr unknown vs unknown (eq)",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1,
+		    offsetof(struct __sk_buff, len)),
+	BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
+	BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
+	BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 1, 3),
+	BPF_LD_MAP_FD(BPF_REG_1, 0),
+	BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 1, 2),
+	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, 11),
+	BPF_LDX_MEM(BPF_B, BPF_REG_4, BPF_REG_0, 0),
+	BPF_JMP_IMM(BPF_JEQ, BPF_REG_4, 1, 4),
+	BPF_MOV64_IMM(BPF_REG_1, 6),
+	BPF_ALU64_IMM(BPF_NEG, BPF_REG_1, 0),
+	BPF_ALU64_IMM(BPF_AND, BPF_REG_1, 0x7),
+	BPF_JMP_IMM(BPF_JA, 0, 0, 3),
+	BPF_MOV64_IMM(BPF_REG_1, 6),
+	BPF_ALU64_IMM(BPF_NEG, BPF_REG_1, 0),
+	BPF_ALU64_IMM(BPF_AND, BPF_REG_1, 0x7),
+	BPF_ALU64_REG(BPF_ADD, BPF_REG_1, BPF_REG_0),
+	BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1, 0),
+	BPF_MOV64_IMM(BPF_REG_0, 1),
+	BPF_EXIT_INSN(),
+	},
+	.fixup_map_hash_16b = { 5 },
+	.fixup_map_array_48b = { 8 },
+	.result = ACCEPT,
+	.retval = 1,
+},
+{
+	"map access: known scalar += value_ptr unknown vs unknown (lt)",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1,
+		    offsetof(struct __sk_buff, len)),
+	BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
+	BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
+	BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 1, 3),
+	BPF_LD_MAP_FD(BPF_REG_1, 0),
+	BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 1, 2),
+	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, 11),
+	BPF_LDX_MEM(BPF_B, BPF_REG_4, BPF_REG_0, 0),
+	BPF_JMP_IMM(BPF_JEQ, BPF_REG_4, 1, 4),
+	BPF_MOV64_IMM(BPF_REG_1, 6),
+	BPF_ALU64_IMM(BPF_NEG, BPF_REG_1, 0),
+	BPF_ALU64_IMM(BPF_AND, BPF_REG_1, 0x3),
+	BPF_JMP_IMM(BPF_JA, 0, 0, 3),
+	BPF_MOV64_IMM(BPF_REG_1, 6),
+	BPF_ALU64_IMM(BPF_NEG, BPF_REG_1, 0),
+	BPF_ALU64_IMM(BPF_AND, BPF_REG_1, 0x7),
+	BPF_ALU64_REG(BPF_ADD, BPF_REG_1, BPF_REG_0),
+	BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1, 0),
+	BPF_MOV64_IMM(BPF_REG_0, 1),
+	BPF_EXIT_INSN(),
+	},
+	.fixup_map_hash_16b = { 5 },
+	.fixup_map_array_48b = { 8 },
+	.result_unpriv = REJECT,
+	.errstr_unpriv = "R1 tried to add from different maps, paths or scalars",
+	.result = ACCEPT,
+	.retval = 1,
+},
+{
+	"map access: known scalar += value_ptr unknown vs unknown (gt)",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1,
+		    offsetof(struct __sk_buff, len)),
+	BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
+	BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
+	BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 1, 3),
+	BPF_LD_MAP_FD(BPF_REG_1, 0),
+	BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 1, 2),
+	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, 11),
+	BPF_LDX_MEM(BPF_B, BPF_REG_4, BPF_REG_0, 0),
+	BPF_JMP_IMM(BPF_JEQ, BPF_REG_4, 1, 4),
+	BPF_MOV64_IMM(BPF_REG_1, 6),
+	BPF_ALU64_IMM(BPF_NEG, BPF_REG_1, 0),
+	BPF_ALU64_IMM(BPF_AND, BPF_REG_1, 0x7),
+	BPF_JMP_IMM(BPF_JA, 0, 0, 3),
+	BPF_MOV64_IMM(BPF_REG_1, 6),
+	BPF_ALU64_IMM(BPF_NEG, BPF_REG_1, 0),
+	BPF_ALU64_IMM(BPF_AND, BPF_REG_1, 0x3),
+	BPF_ALU64_REG(BPF_ADD, BPF_REG_1, BPF_REG_0),
+	BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1, 0),
+	BPF_MOV64_IMM(BPF_REG_0, 1),
+	BPF_EXIT_INSN(),
+	},
+	.fixup_map_hash_16b = { 5 },
+	.fixup_map_array_48b = { 8 },
+	.result_unpriv = REJECT,
+	.errstr_unpriv = "R1 tried to add from different maps, paths or scalars",
+	.result = ACCEPT,
+	.retval = 1,
+},
+{
 	"map access: known scalar += value_ptr from different maps",
 	.insns = {
 	BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1,