Merge tag 'asn1-fixes-20150805' of...

Merge tag 'asn1-fixes-20150805' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs into next

include/linux/asn1_ber_bytecode.h

@@ -45,23 +45,27 @@ enum asn1_opcode {
 	ASN1_OP_MATCH_JUMP		= 0x04,
 	ASN1_OP_MATCH_JUMP_OR_SKIP	= 0x05,
 	ASN1_OP_MATCH_ANY		= 0x08,
+	ASN1_OP_MATCH_ANY_OR_SKIP	= 0x09,
 	ASN1_OP_MATCH_ANY_ACT		= 0x0a,
+	ASN1_OP_MATCH_ANY_ACT_OR_SKIP	= 0x0b,
 	/* Everything before here matches unconditionally */
 
 	ASN1_OP_COND_MATCH_OR_SKIP	= 0x11,
 	ASN1_OP_COND_MATCH_ACT_OR_SKIP	= 0x13,
 	ASN1_OP_COND_MATCH_JUMP_OR_SKIP	= 0x15,
 	ASN1_OP_COND_MATCH_ANY		= 0x18,
+	ASN1_OP_COND_MATCH_ANY_OR_SKIP	= 0x19,
 	ASN1_OP_COND_MATCH_ANY_ACT	= 0x1a,
+	ASN1_OP_COND_MATCH_ANY_ACT_OR_SKIP = 0x1b,
 
 	/* Everything before here will want a tag from the data */
-#define ASN1_OP__MATCHES_TAG ASN1_OP_COND_MATCH_ANY_ACT
+#define ASN1_OP__MATCHES_TAG ASN1_OP_COND_MATCH_ANY_ACT_OR_SKIP
 
 	/* These are here to help fill up space */
-	ASN1_OP_COND_FAIL		= 0x1b,
-	ASN1_OP_COMPLETE		= 0x1c,
-	ASN1_OP_ACT			= 0x1d,
-	ASN1_OP_RETURN			= 0x1e,
+	ASN1_OP_COND_FAIL		= 0x1c,
+	ASN1_OP_COMPLETE		= 0x1d,
+	ASN1_OP_ACT			= 0x1e,
+	ASN1_OP_MAYBE_ACT		= 0x1f,
 
 	/* The following eight have bit 0 -> SET, 1 -> OF, 2 -> ACT */
 	ASN1_OP_END_SEQ			= 0x20,
@@ -76,6 +80,8 @@ enum asn1_opcode {
 #define ASN1_OP_END__OF			  0x02
 #define ASN1_OP_END__ACT		  0x04
 
+	ASN1_OP_RETURN			= 0x28,
+
 	ASN1_OP__NR
 };
 

lib/asn1_decoder.c

@@ -24,15 +24,20 @@ static const unsigned char asn1_op_lengths[ASN1_OP__NR] = {
 	[ASN1_OP_MATCH_JUMP]			= 1 + 1 + 1,
 	[ASN1_OP_MATCH_JUMP_OR_SKIP]		= 1 + 1 + 1,
 	[ASN1_OP_MATCH_ANY]			= 1,
+	[ASN1_OP_MATCH_ANY_OR_SKIP]		= 1,
 	[ASN1_OP_MATCH_ANY_ACT]			= 1         + 1,
+	[ASN1_OP_MATCH_ANY_ACT_OR_SKIP]		= 1         + 1,
 	[ASN1_OP_COND_MATCH_OR_SKIP]		= 1 + 1,
 	[ASN1_OP_COND_MATCH_ACT_OR_SKIP]	= 1 + 1     + 1,
 	[ASN1_OP_COND_MATCH_JUMP_OR_SKIP]	= 1 + 1 + 1,
 	[ASN1_OP_COND_MATCH_ANY]		= 1,
+	[ASN1_OP_COND_MATCH_ANY_OR_SKIP]	= 1,
 	[ASN1_OP_COND_MATCH_ANY_ACT]		= 1         + 1,
+	[ASN1_OP_COND_MATCH_ANY_ACT_OR_SKIP]	= 1         + 1,
 	[ASN1_OP_COND_FAIL]			= 1,
 	[ASN1_OP_COMPLETE]			= 1,
 	[ASN1_OP_ACT]				= 1         + 1,
+	[ASN1_OP_MAYBE_ACT]			= 1         + 1,
 	[ASN1_OP_RETURN]			= 1,
 	[ASN1_OP_END_SEQ]			= 1,
 	[ASN1_OP_END_SEQ_OF]			= 1     + 1,
@@ -177,6 +182,7 @@ int asn1_ber_decoder(const struct asn1_decoder *decoder,
 	unsigned char flags = 0;
 #define FLAG_INDEFINITE_LENGTH	0x01
 #define FLAG_MATCHED		0x02
+#define FLAG_LAST_MATCHED	0x04 /* Last tag matched */
 #define FLAG_CONS		0x20 /* Corresponds to CONS bit in the opcode tag
 				      * - ie. whether or not we are going to parse
 				      *   a compound type.
@@ -208,9 +214,9 @@ int asn1_ber_decoder(const struct asn1_decoder *decoder,
 		unsigned char tmp;
 
 		/* Skip conditional matches if possible */
-		if ((op & ASN1_OP_MATCH__COND &&
-		     flags & FLAG_MATCHED) ||
-		    dp == datalen) {
+		if ((op & ASN1_OP_MATCH__COND && flags & FLAG_MATCHED) ||
+		    (op & ASN1_OP_MATCH__SKIP && dp == datalen)) {
+			flags &= ~FLAG_LAST_MATCHED;
 			pc += asn1_op_lengths[op];
 			goto next_op;
 		}
@@ -302,7 +308,9 @@ int asn1_ber_decoder(const struct asn1_decoder *decoder,
 	/* Decide how to handle the operation */
 	switch (op) {
 	case ASN1_OP_MATCH_ANY_ACT:
+	case ASN1_OP_MATCH_ANY_ACT_OR_SKIP:
 	case ASN1_OP_COND_MATCH_ANY_ACT:
+	case ASN1_OP_COND_MATCH_ANY_ACT_OR_SKIP:
 		ret = actions[machine[pc + 1]](context, hdr, tag, data + dp, len);
 		if (ret < 0)
 			return ret;
@@ -319,8 +327,10 @@ int asn1_ber_decoder(const struct asn1_decoder *decoder,
 	case ASN1_OP_MATCH:
 	case ASN1_OP_MATCH_OR_SKIP:
 	case ASN1_OP_MATCH_ANY:
+	case ASN1_OP_MATCH_ANY_OR_SKIP:
 	case ASN1_OP_COND_MATCH_OR_SKIP:
 	case ASN1_OP_COND_MATCH_ANY:
+	case ASN1_OP_COND_MATCH_ANY_OR_SKIP:
 	skip_data:
 		if (!(flags & FLAG_CONS)) {
 			if (flags & FLAG_INDEFINITE_LENGTH) {
@@ -422,8 +432,15 @@ int asn1_ber_decoder(const struct asn1_decoder *decoder,
 		pc += asn1_op_lengths[op];
 		goto next_op;
 
+	case ASN1_OP_MAYBE_ACT:
+		if (!(flags & FLAG_LAST_MATCHED)) {
+			pc += asn1_op_lengths[op];
+			goto next_op;
+		}
 	case ASN1_OP_ACT:
 		ret = actions[machine[pc + 1]](context, hdr, tag, data + tdp, len);
+		if (ret < 0)
+			return ret;
 		pc += asn1_op_lengths[op];
 		goto next_op;
 
@@ -431,6 +448,7 @@ int asn1_ber_decoder(const struct asn1_decoder *decoder,
 		if (unlikely(jsp <= 0))
 			goto jump_stack_underflow;
 		pc = jump_stack[--jsp];
+		flags |= FLAG_MATCHED | FLAG_LAST_MATCHED;
 		goto next_op;
 
 	default:
@@ -438,7 +456,8 @@ int asn1_ber_decoder(const struct asn1_decoder *decoder,
 	}
 
 	/* Shouldn't reach here */
-	pr_err("ASN.1 decoder error: Found reserved opcode (%u)\n", op);
+	pr_err("ASN.1 decoder error: Found reserved opcode (%u) pc=%zu\n",
+	       op, pc);
 	return -EBADMSG;
 
 data_overrun_error:

scripts/asn1_compiler.c

@@ -666,7 +666,7 @@ struct element {
 	unsigned	flags;
 #define ELEMENT_IMPLICIT	0x0001
 #define ELEMENT_EXPLICIT	0x0002
-#define ELEMENT_MARKED		0x0004
+#define ELEMENT_TAG_SPECIFIED	0x0004
 #define ELEMENT_RENDERED	0x0008
 #define ELEMENT_SKIPPABLE	0x0010
 #define ELEMENT_CONDITIONAL	0x0020
@@ -879,6 +879,7 @@ static struct element *parse_type(struct token **_cursor, struct token *end,
 
 		element->tag &= ~0x1f;
 		element->tag |= strtoul(cursor->value, &p, 10);
+		element->flags |= ELEMENT_TAG_SPECIFIED;
 		if (p - cursor->value != cursor->size)
 			abort();
 		cursor++;
@@ -1376,7 +1377,7 @@ static void render_out_of_line_list(FILE *out)
  */
 static void render_element(FILE *out, struct element *e, struct element *tag)
 {
-	struct element *ec;
+	struct element *ec, *x;
 	const char *cond, *act;
 	int entry, skippable = 0, outofline = 0;
 
@@ -1400,7 +1401,8 @@ static void render_element(FILE *out, struct element *e, struct element *tag)
 	act = e->action ? "_ACT" : "";
 	switch (e->compound) {
 	case ANY:
-		render_opcode(out, "ASN1_OP_%sMATCH_ANY%s,", cond, act);
+		render_opcode(out, "ASN1_OP_%sMATCH_ANY%s%s,",
+			      cond, act, skippable ? "_OR_SKIP" : "");
 		if (e->name)
 			render_more(out, "\t\t// %*.*s",
 				    (int)e->name->size, (int)e->name->size,
@@ -1435,15 +1437,17 @@ static void render_element(FILE *out, struct element *e, struct element *tag)
 		break;
 	}
 
-	if (e->name)
+	x = tag ?: e;
+	if (x->name)
 		render_more(out, "\t\t// %*.*s",
-			    (int)e->name->size, (int)e->name->size,
-			    e->name->value);
+			    (int)x->name->size, (int)x->name->size,
+			    x->name->value);
 	render_more(out, "\n");
 
 	/* Render the tag */
-	if (!tag)
+	if (!tag || !(tag->flags & ELEMENT_TAG_SPECIFIED))
 		tag = e;
+
 	if (tag->class == ASN1_UNIV &&
 	    tag->tag != 14 &&
 	    tag->tag != 15 &&
@@ -1465,7 +1469,8 @@ static void render_element(FILE *out, struct element *e, struct element *tag)
 	case TYPE_REF:
 		render_element(out, e->type->type->element, tag);
 		if (e->action)
-			render_opcode(out, "ASN1_OP_ACT,\n");
+			render_opcode(out, "ASN1_OP_%sACT,\n",
+				      skippable ? "MAYBE_" : "");
 		break;
 
 	case SEQUENCE:
@@ -1539,7 +1544,7 @@ static void render_element(FILE *out, struct element *e, struct element *tag)
 
 	case CHOICE:
 		for (ec = e->children; ec; ec = ec->next)
-			render_element(out, ec, NULL);
+			render_element(out, ec, ec);
 		if (!skippable)
 			render_opcode(out, "ASN1_OP_COND_FAIL,\n");
 		if (e->action)