1 files changed, 296 insertions, 85 deletions

diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index c5b56c92f8e2..6a86723c5b64 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -140,7 +140,7 @@ struct bpf_verifier_stack_elem {
 	struct bpf_verifier_stack_elem *next;
 };
 
-#define BPF_COMPLEXITY_LIMIT_INSNS	65536
+#define BPF_COMPLEXITY_LIMIT_INSNS	98304
 #define BPF_COMPLEXITY_LIMIT_STACK	1024
 
 #define BPF_MAP_PTR_POISON ((void *)0xeB9F + POISON_POINTER_DELTA)
@@ -241,6 +241,12 @@ static void print_verifier_state(struct bpf_verifier_state *state)
 		if (reg->max_value != BPF_REGISTER_MAX_RANGE)
 			verbose(",max_value=%llu",
 				(unsigned long long)reg->max_value);
+		if (reg->min_align)
+			verbose(",min_align=%u", reg->min_align);
+		if (reg->aux_off)
+			verbose(",aux_off=%u", reg->aux_off);
+		if (reg->aux_off_align)
+			verbose(",aux_off_align=%u", reg->aux_off_align);
 	}
 	for (i = 0; i < MAX_BPF_STACK; i += BPF_REG_SIZE) {
 		if (state->stack_slot_type[i] == STACK_SPILL)
@@ -457,16 +463,22 @@ static const int caller_saved[CALLER_SAVED_REGS] = {
 	BPF_REG_0, BPF_REG_1, BPF_REG_2, BPF_REG_3, BPF_REG_4, BPF_REG_5
 };
 
+static void mark_reg_not_init(struct bpf_reg_state *regs, u32 regno)
+{
+	BUG_ON(regno >= MAX_BPF_REG);
+
+	memset(&regs[regno], 0, sizeof(regs[regno]));
+	regs[regno].type = NOT_INIT;
+	regs[regno].min_value = BPF_REGISTER_MIN_RANGE;
+	regs[regno].max_value = BPF_REGISTER_MAX_RANGE;
+}
+
 static void init_reg_state(struct bpf_reg_state *regs)
 {
 	int i;
 
-	for (i = 0; i < MAX_BPF_REG; i++) {
-		regs[i].type = NOT_INIT;
-		regs[i].imm = 0;
-		regs[i].min_value = BPF_REGISTER_MIN_RANGE;
-		regs[i].max_value = BPF_REGISTER_MAX_RANGE;
-	}
+	for (i = 0; i < MAX_BPF_REG; i++)
+		mark_reg_not_init(regs, i);
 
 	/* frame pointer */
 	regs[BPF_REG_FP].type = FRAME_PTR;
@@ -492,6 +504,7 @@ static void reset_reg_range_values(struct bpf_reg_state *regs, u32 regno)
 {
 	regs[regno].min_value = BPF_REGISTER_MIN_RANGE;
 	regs[regno].max_value = BPF_REGISTER_MAX_RANGE;
+	regs[regno].min_align = 0;
 }
 
 static void mark_reg_unknown_value_and_range(struct bpf_reg_state *regs,
@@ -533,20 +546,6 @@ static int check_reg_arg(struct bpf_reg_state *regs, u32 regno,
 	return 0;
 }
 
-static int bpf_size_to_bytes(int bpf_size)
-{
-	if (bpf_size == BPF_W)
-		return 4;
-	else if (bpf_size == BPF_H)
-		return 2;
-	else if (bpf_size == BPF_B)
-		return 1;
-	else if (bpf_size == BPF_DW)
-		return 8;
-	else
-		return -EINVAL;
-}
-
 static bool is_spillable_regtype(enum bpf_reg_type type)
 {
 	switch (type) {
@@ -745,15 +744,29 @@ static int check_packet_access(struct bpf_verifier_env *env, u32 regno, int off,
 }
 
 /* check access to 'struct bpf_context' fields */
-static int check_ctx_access(struct bpf_verifier_env *env, int off, int size,
+static int check_ctx_access(struct bpf_verifier_env *env, int insn_idx, int off, int size,
 			    enum bpf_access_type t, enum bpf_reg_type *reg_type)
 {
+	struct bpf_insn_access_aux info = {
+		.reg_type = *reg_type,
+	};
+
 	/* for analyzer ctx accesses are already validated and converted */
 	if (env->analyzer_ops)
 		return 0;
 
 	if (env->prog->aux->ops->is_valid_access &&
-	    env->prog->aux->ops->is_valid_access(off, size, t, reg_type)) {
+	    env->prog->aux->ops->is_valid_access(off, size, t, &info)) {
+		/* A non zero info.ctx_field_size indicates that this field is a
+		 * candidate for later verifier transformation to load the whole
+		 * field and then apply a mask when accessed with a narrower
+		 * access than actual ctx access size. A zero info.ctx_field_size
+		 * will only allow for whole field access and rejects any other
+		 * type of narrower access.
+		 */
+		env->insn_aux_data[insn_idx].ctx_field_size = info.ctx_field_size;
+		*reg_type = info.reg_type;
+
 		/* remember the offset of last byte accessed in ctx */
 		if (env->prog->aux->max_ctx_offset < off + size)
 			env->prog->aux->max_ctx_offset = off + size;
@@ -779,17 +792,37 @@ static bool is_pointer_value(struct bpf_verifier_env *env, int regno)
 }
 
 static int check_pkt_ptr_alignment(const struct bpf_reg_state *reg,
-				   int off, int size)
+				   int off, int size, bool strict)
 {
-	if (reg->id && size != 1) {
-		verbose("Unknown alignment. Only byte-sized access allowed in packet access.\n");
-		return -EACCES;
+	int ip_align;
+	int reg_off;
+
+	/* Byte size accesses are always allowed. */
+	if (!strict || size == 1)
+		return 0;
+
+	reg_off = reg->off;
+	if (reg->id) {
+		if (reg->aux_off_align % size) {
+			verbose("Packet access is only %u byte aligned, %d byte access not allowed\n",
+				reg->aux_off_align, size);
+			return -EACCES;
+		}
+		reg_off += reg->aux_off;
 	}
 
-	/* skb->data is NET_IP_ALIGN-ed */
-	if ((NET_IP_ALIGN + reg->off + off) % size != 0) {
+	/* For platforms that do not have a Kconfig enabling
+	 * CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS the value of
+	 * NET_IP_ALIGN is universally set to '2'.  And on platforms
+	 * that do set CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS, we get
+	 * to this code only in strict mode where we want to emulate
+	 * the NET_IP_ALIGN==2 checking.  Therefore use an
+	 * unconditional IP align value of '2'.
+	 */
+	ip_align = 2;
+	if ((ip_align + reg_off + off) % size != 0) {
 		verbose("misaligned packet access off %d+%d+%d size %d\n",
-			NET_IP_ALIGN, reg->off, off, size);
+			ip_align, reg_off, off, size);
 		return -EACCES;
 	}
 
@@ -797,9 +830,9 @@ static int check_pkt_ptr_alignment(const struct bpf_reg_state *reg,
 }
 
 static int check_val_ptr_alignment(const struct bpf_reg_state *reg,
-				   int size)
+				   int size, bool strict)
 {
-	if (size != 1) {
+	if (strict && size != 1) {
 		verbose("Unknown alignment. Only byte-sized access allowed in value access.\n");
 		return -EACCES;
 	}
@@ -807,16 +840,17 @@ static int check_val_ptr_alignment(const struct bpf_reg_state *reg,
 	return 0;
 }
 
-static int check_ptr_alignment(const struct bpf_reg_state *reg,
+static int check_ptr_alignment(struct bpf_verifier_env *env,
+			       const struct bpf_reg_state *reg,
 			       int off, int size)
 {
+	bool strict = env->strict_alignment;
+
 	switch (reg->type) {
 	case PTR_TO_PACKET:
-		return IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) ? 0 :
-		       check_pkt_ptr_alignment(reg, off, size);
+		return check_pkt_ptr_alignment(reg, off, size, strict);
 	case PTR_TO_MAP_VALUE_ADJ:
-		return IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) ? 0 :
-		       check_val_ptr_alignment(reg, size);
+		return check_val_ptr_alignment(reg, size, strict);
 	default:
 		if (off % size != 0) {
 			verbose("misaligned access off %d size %d\n",
@@ -834,7 +868,7 @@ static int check_ptr_alignment(const struct bpf_reg_state *reg,
  * if t==write && value_regno==-1, some unknown value is stored into memory
  * if t==read && value_regno==-1, don't care what we read from memory
  */
-static int check_mem_access(struct bpf_verifier_env *env, u32 regno, int off,
+static int check_mem_access(struct bpf_verifier_env *env, int insn_idx, u32 regno, int off,
 			    int bpf_size, enum bpf_access_type t,
 			    int value_regno)
 {
@@ -849,7 +883,7 @@ static int check_mem_access(struct bpf_verifier_env *env, u32 regno, int off,
 	if (size < 0)
 		return size;
 
-	err = check_ptr_alignment(reg, off, size);
+	err = check_ptr_alignment(env, reg, off, size);
 	if (err)
 		return err;
 
@@ -877,12 +911,14 @@ static int check_mem_access(struct bpf_verifier_env *env, u32 regno, int off,
 			verbose("R%d leaks addr into ctx\n", value_regno);
 			return -EACCES;
 		}
-		err = check_ctx_access(env, off, size, t, &reg_type);
+		err = check_ctx_access(env, insn_idx, off, size, t, &reg_type);
 		if (!err && t == BPF_READ && value_regno >= 0) {
 			mark_reg_unknown_value_and_range(state->regs,
 							 value_regno);
 			/* note that reg.[id|off|range] == 0 */
 			state->regs[value_regno].type = reg_type;
+			state->regs[value_regno].aux_off = 0;
+			state->regs[value_regno].aux_off_align = 0;
 		}
 
 	} else if (reg->type == FRAME_PTR || reg->type == PTR_TO_STACK) {
@@ -890,6 +926,10 @@ static int check_mem_access(struct bpf_verifier_env *env, u32 regno, int off,
 			verbose("invalid stack off=%d size=%d\n", off, size);
 			return -EACCES;
 		}
+
+		if (env->prog->aux->stack_depth < -off)
+			env->prog->aux->stack_depth = -off;
+
 		if (t == BPF_WRITE) {
 			if (!env->allow_ptr_leaks &&
 			    state->stack_slot_type[MAX_BPF_STACK + off] == STACK_SPILL &&
@@ -932,7 +972,7 @@ static int check_mem_access(struct bpf_verifier_env *env, u32 regno, int off,
 	return err;
 }
 
-static int check_xadd(struct bpf_verifier_env *env, struct bpf_insn *insn)
+static int check_xadd(struct bpf_verifier_env *env, int insn_idx, struct bpf_insn *insn)
 {
 	struct bpf_reg_state *regs = env->cur_state.regs;
 	int err;
@@ -953,14 +993,19 @@ static int check_xadd(struct bpf_verifier_env *env, struct bpf_insn *insn)
 	if (err)
 		return err;
 
+	if (is_pointer_value(env, insn->src_reg)) {
+		verbose("R%d leaks addr into mem\n", insn->src_reg);
+		return -EACCES;
+	}
+
 	/* check whether atomic_add can read the memory */
-	err = check_mem_access(env, insn->dst_reg, insn->off,
+	err = check_mem_access(env, insn_idx, insn->dst_reg, insn->off,
 			       BPF_SIZE(insn->code), BPF_READ, -1);
 	if (err)
 		return err;
 
 	/* check whether atomic_add can write into the same memory */
-	return check_mem_access(env, insn->dst_reg, insn->off,
+	return check_mem_access(env, insn_idx, insn->dst_reg, insn->off,
 				BPF_SIZE(insn->code), BPF_WRITE, -1);
 }
 
@@ -996,6 +1041,9 @@ static int check_stack_boundary(struct bpf_verifier_env *env, int regno,
 		return -EACCES;
 	}
 
+	if (env->prog->aux->stack_depth < -off)
+		env->prog->aux->stack_depth = -off;
+
 	if (meta && meta->raw_mode) {
 		meta->access_size = access_size;
 		meta->regno = regno;
@@ -1303,8 +1351,8 @@ static void clear_all_pkt_pointers(struct bpf_verifier_env *env)
 		if (reg->type != PTR_TO_PACKET &&
 		    reg->type != PTR_TO_PACKET_END)
 			continue;
-		reg->type = UNKNOWN_VALUE;
-		reg->imm = 0;
+		__mark_reg_unknown_value(state->spilled_regs,
+					 i / BPF_REG_SIZE);
 	}
 }
 
@@ -1313,7 +1361,6 @@ static int check_call(struct bpf_verifier_env *env, int func_id, int insn_idx)
 	struct bpf_verifier_state *state = &env->cur_state;
 	const struct bpf_func_proto *fn = NULL;
 	struct bpf_reg_state *regs = state->regs;
-	struct bpf_reg_state *reg;
 	struct bpf_call_arg_meta meta;
 	bool changes_data;
 	int i, err;
@@ -1374,17 +1421,14 @@ static int check_call(struct bpf_verifier_env *env, int func_id, int insn_idx)
 	 * is inferred from register state.
 	 */
 	for (i = 0; i < meta.access_size; i++) {
-		err = check_mem_access(env, meta.regno, i, BPF_B, BPF_WRITE, -1);
+		err = check_mem_access(env, insn_idx, meta.regno, i, BPF_B, BPF_WRITE, -1);
 		if (err)
 			return err;
 	}
 
 	/* reset caller saved regs */
-	for (i = 0; i < CALLER_SAVED_REGS; i++) {
-		reg = regs + caller_saved[i];
-		reg->type = NOT_INIT;
-		reg->imm = 0;
-	}
+	for (i = 0; i < CALLER_SAVED_REGS; i++)
+		mark_reg_not_init(regs, caller_saved[i]);
 
 	/* update return register */
 	if (fn->ret_type == RET_INTEGER) {
@@ -1455,6 +1499,8 @@ add_imm:
 		 */
 		dst_reg->off += imm;
 	} else {
+		bool had_id;
+
 		if (src_reg->type == PTR_TO_PACKET) {
 			/* R6=pkt(id=0,off=0,r=62) R7=imm22; r7 += r6 */
 			tmp_reg = *dst_reg;  /* save r7 state */
@@ -1488,14 +1534,23 @@ add_imm:
 				src_reg->imm);
 			return -EACCES;
 		}
+
+		had_id = (dst_reg->id != 0);
+
 		/* dst_reg stays as pkt_ptr type and since some positive
 		 * integer value was added to the pointer, increment its 'id'
 		 */
 		dst_reg->id = ++env->id_gen;
 
-		/* something was added to pkt_ptr, set range and off to zero */
+		/* something was added to pkt_ptr, set range to zero */
+		dst_reg->aux_off += dst_reg->off;
 		dst_reg->off = 0;
 		dst_reg->range = 0;
+		if (had_id)
+			dst_reg->aux_off_align = min(dst_reg->aux_off_align,
+						     src_reg->min_align);
+		else
+			dst_reg->aux_off_align = src_reg->min_align;
 	}
 	return 0;
 }
@@ -1602,6 +1657,65 @@ static int evaluate_reg_alu(struct bpf_verifier_env *env, struct bpf_insn *insn)
 	return 0;
 }
 
+static int evaluate_reg_imm_alu_unknown(struct bpf_verifier_env *env,
+					struct bpf_insn *insn)
+{
+	struct bpf_reg_state *regs = env->cur_state.regs;
+	struct bpf_reg_state *dst_reg = &regs[insn->dst_reg];
+	struct bpf_reg_state *src_reg = &regs[insn->src_reg];
+	u8 opcode = BPF_OP(insn->code);
+	s64 imm_log2 = __ilog2_u64((long long)dst_reg->imm);
+
+	/* BPF_X code with src_reg->type UNKNOWN_VALUE here. */
+	if (src_reg->imm > 0 && dst_reg->imm) {
+		switch (opcode) {
+		case BPF_ADD:
+			/* dreg += sreg
+			 * where both have zero upper bits. Adding them
+			 * can only result making one more bit non-zero
+			 * in the larger value.
+			 * Ex. 0xffff (imm=48) + 1 (imm=63) = 0x10000 (imm=47)
+			 *     0xffff (imm=48) + 0xffff = 0x1fffe (imm=47)
+			 */
+			dst_reg->imm = min(src_reg->imm, 63 - imm_log2);
+			dst_reg->imm--;
+			break;
+		case BPF_AND:
+			/* dreg &= sreg
+			 * AND can not extend zero bits only shrink
+			 * Ex.  0x00..00ffffff
+			 *    & 0x0f..ffffffff
+			 *     ----------------
+			 *      0x00..00ffffff
+			 */
+			dst_reg->imm = max(src_reg->imm, 63 - imm_log2);
+			break;
+		case BPF_OR:
+			/* dreg |= sreg
+			 * OR can only extend zero bits
+			 * Ex.  0x00..00ffffff
+			 *    | 0x0f..ffffffff
+			 *     ----------------
+			 *      0x0f..00ffffff
+			 */
+			dst_reg->imm = min(src_reg->imm, 63 - imm_log2);
+			break;
+		case BPF_SUB:
+		case BPF_MUL:
+		case BPF_RSH:
+		case BPF_LSH:
+			/* These may be flushed out later */
+		default:
+			mark_reg_unknown_value(regs, insn->dst_reg);
+		}
+	} else {
+		mark_reg_unknown_value(regs, insn->dst_reg);
+	}
+
+	dst_reg->type = UNKNOWN_VALUE;
+	return 0;
+}
+
 static int evaluate_reg_imm_alu(struct bpf_verifier_env *env,
 				struct bpf_insn *insn)
 {
@@ -1611,6 +1725,9 @@ static int evaluate_reg_imm_alu(struct bpf_verifier_env *env,
 	u8 opcode = BPF_OP(insn->code);
 	u64 dst_imm = dst_reg->imm;
 
+	if (BPF_SRC(insn->code) == BPF_X && src_reg->type == UNKNOWN_VALUE)
+		return evaluate_reg_imm_alu_unknown(env, insn);
+
 	/* dst_reg->type == CONST_IMM here. Simulate execution of insns
 	 * containing ALU ops. Don't care about overflow or negative
 	 * values, just add/sub/... them; registers are in u64.
@@ -1669,6 +1786,13 @@ static void check_reg_overflow(struct bpf_reg_state *reg)
 		reg->min_value = BPF_REGISTER_MIN_RANGE;
 }
 
+static u32 calc_align(u32 imm)
+{
+	if (!imm)
+		return 1U << 31;
+	return imm - ((imm - 1) & imm);
+}
+
 static void adjust_reg_min_max_vals(struct bpf_verifier_env *env,
 				    struct bpf_insn *insn)
 {
@@ -1676,8 +1800,10 @@ static void adjust_reg_min_max_vals(struct bpf_verifier_env *env,
 	s64 min_val = BPF_REGISTER_MIN_RANGE;
 	u64 max_val = BPF_REGISTER_MAX_RANGE;
 	u8 opcode = BPF_OP(insn->code);
+	u32 dst_align, src_align;
 
 	dst_reg = &regs[insn->dst_reg];
+	src_align = 0;
 	if (BPF_SRC(insn->code) == BPF_X) {
 		check_reg_overflow(&regs[insn->src_reg]);
 		min_val = regs[insn->src_reg].min_value;
@@ -1693,12 +1819,18 @@ static void adjust_reg_min_max_vals(struct bpf_verifier_env *env,
 		    regs[insn->src_reg].type != UNKNOWN_VALUE) {
 			min_val = BPF_REGISTER_MIN_RANGE;
 			max_val = BPF_REGISTER_MAX_RANGE;
+			src_align = 0;
+		} else {
+			src_align = regs[insn->src_reg].min_align;
 		}
 	} else if (insn->imm < BPF_REGISTER_MAX_RANGE &&
 		   (s64)insn->imm > BPF_REGISTER_MIN_RANGE) {
 		min_val = max_val = insn->imm;
+		src_align = calc_align(insn->imm);
 	}
 
+	dst_align = dst_reg->min_align;
+
 	/* We don't know anything about what was done to this register, mark it
 	 * as unknown.
 	 */
@@ -1723,18 +1855,21 @@ static void adjust_reg_min_max_vals(struct bpf_verifier_env *env,
 			dst_reg->min_value += min_val;
 		if (dst_reg->max_value != BPF_REGISTER_MAX_RANGE)
 			dst_reg->max_value += max_val;
+		dst_reg->min_align = min(src_align, dst_align);
 		break;
 	case BPF_SUB:
 		if (dst_reg->min_value != BPF_REGISTER_MIN_RANGE)
 			dst_reg->min_value -= min_val;
 		if (dst_reg->max_value != BPF_REGISTER_MAX_RANGE)
 			dst_reg->max_value -= max_val;
+		dst_reg->min_align = min(src_align, dst_align);
 		break;
 	case BPF_MUL:
 		if (dst_reg->min_value != BPF_REGISTER_MIN_RANGE)
 			dst_reg->min_value *= min_val;
 		if (dst_reg->max_value != BPF_REGISTER_MAX_RANGE)
 			dst_reg->max_value *= max_val;
+		dst_reg->min_align = max(src_align, dst_align);
 		break;
 	case BPF_AND:
 		/* Disallow AND'ing of negative numbers, ain't nobody got time
@@ -1746,17 +1881,23 @@ static void adjust_reg_min_max_vals(struct bpf_verifier_env *env,
 		else
 			dst_reg->min_value = 0;
 		dst_reg->max_value = max_val;
+		dst_reg->min_align = max(src_align, dst_align);
 		break;
 	case BPF_LSH:
 		/* Gotta have special overflow logic here, if we're shifting
 		 * more than MAX_RANGE then just assume we have an invalid
 		 * range.
 		 */
-		if (min_val > ilog2(BPF_REGISTER_MAX_RANGE))
+		if (min_val > ilog2(BPF_REGISTER_MAX_RANGE)) {
 			dst_reg->min_value = BPF_REGISTER_MIN_RANGE;
-		else if (dst_reg->min_value != BPF_REGISTER_MIN_RANGE)
-			dst_reg->min_value <<= min_val;
-
+			dst_reg->min_align = 1;
+		} else {
+			if (dst_reg->min_value != BPF_REGISTER_MIN_RANGE)
+				dst_reg->min_value <<= min_val;
+			if (!dst_reg->min_align)
+				dst_reg->min_align = 1;
+			dst_reg->min_align <<= min_val;
+		}
 		if (max_val > ilog2(BPF_REGISTER_MAX_RANGE))
 			dst_reg->max_value = BPF_REGISTER_MAX_RANGE;
 		else if (dst_reg->max_value != BPF_REGISTER_MAX_RANGE)
@@ -1766,11 +1907,19 @@ static void adjust_reg_min_max_vals(struct bpf_verifier_env *env,
 		/* RSH by a negative number is undefined, and the BPF_RSH is an
 		 * unsigned shift, so make the appropriate casts.
 		 */
-		if (min_val < 0 || dst_reg->min_value < 0)
+		if (min_val < 0 || dst_reg->min_value < 0) {
 			dst_reg->min_value = BPF_REGISTER_MIN_RANGE;
-		else
+		} else {
 			dst_reg->min_value =
 				(u64)(dst_reg->min_value) >> min_val;
+		}
+		if (min_val < 0) {
+			dst_reg->min_align = 1;
+		} else {
+			dst_reg->min_align >>= (u64) min_val;
+			if (!dst_reg->min_align)
+				dst_reg->min_align = 1;
+		}
 		if (dst_reg->max_value != BPF_REGISTER_MAX_RANGE)
 			dst_reg->max_value >>= max_val;
 		break;
@@ -1870,8 +2019,10 @@ static int check_alu_op(struct bpf_verifier_env *env, struct bpf_insn *insn)
 			 */
 			regs[insn->dst_reg].type = CONST_IMM;
 			regs[insn->dst_reg].imm = insn->imm;
+			regs[insn->dst_reg].id = 0;
 			regs[insn->dst_reg].max_value = insn->imm;
 			regs[insn->dst_reg].min_value = insn->imm;
+			regs[insn->dst_reg].min_align = calc_align(insn->imm);
 		}
 
 	} else if (opcode > BPF_END) {
@@ -2326,6 +2477,7 @@ static int check_ld_imm(struct bpf_verifier_env *env, struct bpf_insn *insn)
 
 		regs[insn->dst_reg].type = CONST_IMM;
 		regs[insn->dst_reg].imm = imm;
+		regs[insn->dst_reg].id = 0;
 		return 0;
 	}
 
@@ -2368,7 +2520,6 @@ static int check_ld_abs(struct bpf_verifier_env *env, struct bpf_insn *insn)
 {
 	struct bpf_reg_state *regs = env->cur_state.regs;
 	u8 mode = BPF_MODE(insn->code);
-	struct bpf_reg_state *reg;
 	int i, err;
 
 	if (!may_access_skb(env->prog->type)) {
@@ -2401,11 +2552,8 @@ static int check_ld_abs(struct bpf_verifier_env *env, struct bpf_insn *insn)
 	}
 
 	/* reset caller saved regs to unreadable */
-	for (i = 0; i < CALLER_SAVED_REGS; i++) {
-		reg = regs + caller_saved[i];
-		reg->type = NOT_INIT;
-		reg->imm = 0;
-	}
+	for (i = 0; i < CALLER_SAVED_REGS; i++)
+		mark_reg_not_init(regs, caller_saved[i]);
 
 	/* mark destination R0 register as readable, since it contains
 	 * the value fetched from the packet
@@ -2564,6 +2712,7 @@ peek_stack:
 				env->explored_states[t + 1] = STATE_LIST_MARK;
 		} else {
 			/* conditional jump with two edges */
+			env->explored_states[t] = STATE_LIST_MARK;
 			ret = push_insn(t, t + 1, FALLTHROUGH, env);
 			if (ret == 1)
 				goto peek_stack;
@@ -2615,7 +2764,8 @@ err_free:
 /* the following conditions reduce the number of explored insns
  * from ~140k to ~80k for ultra large programs that use a lot of ptr_to_packet
  */
-static bool compare_ptrs_to_packet(struct bpf_reg_state *old,
+static bool compare_ptrs_to_packet(struct bpf_verifier_env *env,
+				   struct bpf_reg_state *old,
 				   struct bpf_reg_state *cur)
 {
 	if (old->id != cur->id)
@@ -2658,7 +2808,7 @@ static bool compare_ptrs_to_packet(struct bpf_reg_state *old,
 	 * 'if (R4 > data_end)' and all further insn were already good with r=20,
 	 * so they will be good with r=30 and we can prune the search.
 	 */
-	if (old->off <= cur->off &&
+	if (!env->strict_alignment && old->off <= cur->off &&
 	    old->off >= old->range && cur->off >= cur->range)
 		return true;
 
@@ -2722,8 +2872,14 @@ static bool states_equal(struct bpf_verifier_env *env,
 		     rcur->type != NOT_INIT))
 			continue;
 
+		/* Don't care about the reg->id in this case. */
+		if (rold->type == PTR_TO_MAP_VALUE_OR_NULL &&
+		    rcur->type == PTR_TO_MAP_VALUE_OR_NULL &&
+		    rold->map_ptr == rcur->map_ptr)
+			continue;
+
 		if (rold->type == PTR_TO_PACKET && rcur->type == PTR_TO_PACKET &&
-		    compare_ptrs_to_packet(rold, rcur))
+		    compare_ptrs_to_packet(env, rold, rcur))
 			continue;
 
 		return false;
@@ -2741,6 +2897,8 @@ static bool states_equal(struct bpf_verifier_env *env,
 			return false;
 		if (i % BPF_REG_SIZE)
 			continue;
+		if (old->stack_slot_type[i] != STACK_SPILL)
+			continue;
 		if (memcmp(&old->spilled_regs[i / BPF_REG_SIZE],
 			   &cur->spilled_regs[i / BPF_REG_SIZE],
 			   sizeof(old->spilled_regs[0])))
@@ -2856,8 +3014,15 @@ static int do_check(struct bpf_verifier_env *env)
 			goto process_bpf_exit;
 		}
 
-		if (log_level && do_print_state) {
-			verbose("\nfrom %d to %d:", prev_insn_idx, insn_idx);
+		if (need_resched())
+			cond_resched();
+
+		if (log_level > 1 || (log_level && do_print_state)) {
+			if (log_level > 1)
+				verbose("%d:", insn_idx);
+			else
+				verbose("\nfrom %d to %d:",
+					prev_insn_idx, insn_idx);
 			print_verifier_state(&env->cur_state);
 			do_print_state = false;
 		}
@@ -2895,18 +3060,12 @@ static int do_check(struct bpf_verifier_env *env)
 			/* check that memory (src_reg + off) is readable,
 			 * the state of dst_reg will be updated by this func
 			 */
-			err = check_mem_access(env, insn->src_reg, insn->off,
+			err = check_mem_access(env, insn_idx, insn->src_reg, insn->off,
 					       BPF_SIZE(insn->code), BPF_READ,
 					       insn->dst_reg);
 			if (err)
 				return err;
 
-			if (BPF_SIZE(insn->code) != BPF_W &&
-			    BPF_SIZE(insn->code) != BPF_DW) {
-				insn_idx++;
-				continue;
-			}
-
 			prev_src_type = &env->insn_aux_data[insn_idx].ptr_type;
 
 			if (*prev_src_type == NOT_INIT) {
@@ -2934,7 +3093,7 @@ static int do_check(struct bpf_verifier_env *env)
 			enum bpf_reg_type *prev_dst_type, dst_reg_type;
 
 			if (BPF_MODE(insn->code) == BPF_XADD) {
-				err = check_xadd(env, insn);
+				err = check_xadd(env, insn_idx, insn);
 				if (err)
 					return err;
 				insn_idx++;
@@ -2953,7 +3112,7 @@ static int do_check(struct bpf_verifier_env *env)
 			dst_reg_type = regs[insn->dst_reg].type;
 
 			/* check that memory (dst_reg + off) is writeable */
-			err = check_mem_access(env, insn->dst_reg, insn->off,
+			err = check_mem_access(env, insn_idx, insn->dst_reg, insn->off,
 					       BPF_SIZE(insn->code), BPF_WRITE,
 					       insn->src_reg);
 			if (err)
@@ -2982,7 +3141,7 @@ static int do_check(struct bpf_verifier_env *env)
 				return err;
 
 			/* check that memory (dst_reg + off) is writeable */
-			err = check_mem_access(env, insn->dst_reg, insn->off,
+			err = check_mem_access(env, insn_idx, insn->dst_reg, insn->off,
 					       BPF_SIZE(insn->code), BPF_WRITE,
 					       -1);
 			if (err)
@@ -3080,7 +3239,8 @@ process_bpf_exit:
 		insn_idx++;
 	}
 
-	verbose("processed %d insns\n", insn_processed);
+	verbose("processed %d insns, stack depth %d\n",
+		insn_processed, env->prog->aux->stack_depth);
 	return 0;
 }
 
@@ -3280,11 +3440,13 @@ static struct bpf_prog *bpf_patch_insn_data(struct bpf_verifier_env *env, u32 of
 static int convert_ctx_accesses(struct bpf_verifier_env *env)
 {
 	const struct bpf_verifier_ops *ops = env->prog->aux->ops;
+	int i, cnt, size, ctx_field_size, delta = 0;
 	const int insn_cnt = env->prog->len;
 	struct bpf_insn insn_buf[16], *insn;
 	struct bpf_prog *new_prog;
 	enum bpf_access_type type;
-	int i, cnt, delta = 0;
+	bool is_narrower_load;
+	u32 target_size;
 
 	if (ops->gen_prologue) {
 		cnt = ops->gen_prologue(insn_buf, env->seen_direct_write,
@@ -3324,12 +3486,52 @@ static int convert_ctx_accesses(struct bpf_verifier_env *env)
 		if (env->insn_aux_data[i + delta].ptr_type != PTR_TO_CTX)
 			continue;
 
-		cnt = ops->convert_ctx_access(type, insn, insn_buf, env->prog);
-		if (cnt == 0 || cnt >= ARRAY_SIZE(insn_buf)) {
+		ctx_field_size = env->insn_aux_data[i + delta].ctx_field_size;
+		size = BPF_LDST_BYTES(insn);
+
+		/* If the read access is a narrower load of the field,
+		 * convert to a 4/8-byte load, to minimum program type specific
+		 * convert_ctx_access changes. If conversion is successful,
+		 * we will apply proper mask to the result.
+		 */
+		is_narrower_load = size < ctx_field_size;
+		if (is_narrower_load) {
+			u32 off = insn->off;
+			u8 size_code;
+
+			if (type == BPF_WRITE) {
+				verbose("bpf verifier narrow ctx access misconfigured\n");
+				return -EINVAL;
+			}
+
+			size_code = BPF_H;
+			if (ctx_field_size == 4)
+				size_code = BPF_W;
+			else if (ctx_field_size == 8)
+				size_code = BPF_DW;
+
+			insn->off = off & ~(ctx_field_size - 1);
+			insn->code = BPF_LDX | BPF_MEM | size_code;
+		}
+
+		target_size = 0;
+		cnt = ops->convert_ctx_access(type, insn, insn_buf, env->prog,
+					      &target_size);
+		if (cnt == 0 || cnt >= ARRAY_SIZE(insn_buf) ||
+		    (ctx_field_size && !target_size)) {
 			verbose("bpf verifier is misconfigured\n");
 			return -EINVAL;
 		}
 
+		if (is_narrower_load && size < target_size) {
+			if (ctx_field_size <= 4)
+				insn_buf[cnt++] = BPF_ALU32_IMM(BPF_AND, insn->dst_reg,
+								(1 << size * 8) - 1);
+			else
+				insn_buf[cnt++] = BPF_ALU64_IMM(BPF_AND, insn->dst_reg,
+								(1 << size * 8) - 1);
+		}
+
 		new_prog = bpf_patch_insn_data(env, i + delta, insn_buf, cnt);
 		if (!new_prog)
 			return -ENOMEM;
@@ -3375,6 +3577,7 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env)
 			 * the program array.
 			 */
 			prog->cb_access = 1;
+			env->prog->aux->stack_depth = MAX_BPF_STACK;
 
 			/* mark bpf_tail_call as different opcode to avoid
 			 * conditional branch in the interpeter for every normal
@@ -3382,7 +3585,7 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env)
 			 * that doesn't support bpf_tail_call yet
 			 */
 			insn->imm = 0;
-			insn->code |= BPF_X;
+			insn->code = BPF_JMP | BPF_TAIL_CALL;
 			continue;
 		}
 
@@ -3495,6 +3698,10 @@ int bpf_check(struct bpf_prog **prog, union bpf_attr *attr)
 		log_level = 0;
 	}
 
+	env->strict_alignment = !!(attr->prog_flags & BPF_F_STRICT_ALIGNMENT);
+	if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS))
+		env->strict_alignment = true;
+
 	ret = replace_map_fd_with_map_ptr(env);
 	if (ret < 0)
 		goto skip_full_check;
@@ -3600,6 +3807,10 @@ int bpf_analyzer(struct bpf_prog *prog, const struct bpf_ext_analyzer_ops *ops,
 
 	log_level = 0;
 
+	env->strict_alignment = false;
+	if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS))
+		env->strict_alignment = true;
+
 	env->explored_states = kcalloc(env->prog->len,
 				       sizeof(struct bpf_verifier_state_list *),
 				       GFP_KERNEL);