diff --git a/include/linux/asn1_ber_bytecode.h b/include/linux/asn1_ber_bytecode.h index 945d44ae529c..27f35780aecf 100644 --- a/include/linux/asn1_ber_bytecode.h +++ b/include/linux/asn1_ber_bytecode.h @@ -61,7 +61,8 @@ enum asn1_opcode { ASN1_OP_COND_FAIL = 0x1b, ASN1_OP_COMPLETE = 0x1c, ASN1_OP_ACT = 0x1d, - ASN1_OP_RETURN = 0x1e, + ASN1_OP_MAYBE_ACT = 0x1e, + ASN1_OP_RETURN = 0x1f, /* The following eight have bit 0 -> SET, 1 -> OF, 2 -> ACT */ ASN1_OP_END_SEQ = 0x20, diff --git a/lib/asn1_decoder.c b/lib/asn1_decoder.c index 1a000bb050f9..55980d7e1ac0 100644 --- a/lib/asn1_decoder.c +++ b/lib/asn1_decoder.c @@ -33,6 +33,7 @@ static const unsigned char asn1_op_lengths[ASN1_OP__NR] = { [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 +178,7 @@ 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. @@ -211,6 +213,7 @@ int asn1_ber_decoder(const struct asn1_decoder *decoder, if ((op & ASN1_OP_MATCH__COND && flags & FLAG_MATCHED) || dp == datalen) { + flags &= ~FLAG_LAST_MATCHED; pc += asn1_op_lengths[op]; goto next_op; } @@ -422,8 +425,15 @@ 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 +441,7 @@ 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 +449,8 @@ 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: diff --git a/scripts/asn1_compiler.c b/scripts/asn1_compiler.c index e87359cd23c0..0515bced929a 100644 --- a/scripts/asn1_compiler.c +++ b/scripts/asn1_compiler.c @@ -1468,7 +1468,8 @@ 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: