1 files changed, 228 insertions, 177 deletions

diff --git a/qapi/string-input-visitor.c b/qapi/string-input-visitor.c
index b89c6c4e06..bd92080667 100644
--- a/qapi/string-input-visitor.c
+++ b/qapi/string-input-visitor.c
@@ -4,10 +4,10 @@
  * Copyright Red Hat, Inc. 2012-2016
  *
  * Author: Paolo Bonzini <pbonzini@redhat.com>
+ *         David Hildenbrand <david@redhat.com>
  *
  * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
  * See the COPYING.LIB file in the top-level directory.
- *
  */
 
 #include "qemu/osdep.h"
@@ -18,21 +18,42 @@
 #include "qapi/qmp/qerror.h"
 #include "qapi/qmp/qnull.h"
 #include "qemu/option.h"
-#include "qemu/queue.h"
-#include "qemu/range.h"
 #include "qemu/cutils.h"
 
+typedef enum ListMode {
+    /* no list parsing active / no list expected */
+    LM_NONE,
+    /* we have an unparsed string remaining */
+    LM_UNPARSED,
+    /* we have an unfinished int64 range */
+    LM_INT64_RANGE,
+    /* we have an unfinished uint64 range */
+    LM_UINT64_RANGE,
+    /* we have parsed the string completely and no range is remaining */
+    LM_END,
+} ListMode;
+
+/* protect against DOS attacks, limit the amount of elements per range */
+#define RANGE_MAX_ELEMENTS 65536
+
+typedef union RangeElement {
+    int64_t i64;
+    uint64_t u64;
+} RangeElement;
 
 struct StringInputVisitor
 {
     Visitor visitor;
 
-    GList *ranges;
-    GList *cur_range;
-    int64_t cur;
+    /* List parsing state */
+    ListMode lm;
+    RangeElement rangeNext;
+    RangeElement rangeEnd;
+    const char *unparsed_string;
+    void *list;
 
+    /* The original string to parse */
     const char *string;
-    void *list; /* Only needed for sanity checking the caller */
 };
 
 static StringInputVisitor *to_siv(Visitor *v)
@@ -40,136 +61,42 @@ static StringInputVisitor *to_siv(Visitor *v)
     return container_of(v, StringInputVisitor, visitor);
 }
 
-static void free_range(void *range, void *dummy)
-{
-    g_free(range);
-}
-
-static int parse_str(StringInputVisitor *siv, const char *name, Error **errp)
-{
-    char *str = (char *) siv->string;
-    long long start, end;
-    Range *cur;
-    char *endptr;
-
-    if (siv->ranges) {
-        return 0;
-    }
-
-    if (!*str) {
-        return 0;
-    }
-
-    do {
-        errno = 0;
-        start = strtoll(str, &endptr, 0);
-        if (errno == 0 && endptr > str) {
-            if (*endptr == '\0') {
-                cur = g_malloc0(sizeof(*cur));
-                range_set_bounds(cur, start, start);
-                siv->ranges = range_list_insert(siv->ranges, cur);
-                cur = NULL;
-                str = NULL;
-            } else if (*endptr == '-') {
-                str = endptr + 1;
-                errno = 0;
-                end = strtoll(str, &endptr, 0);
-                if (errno == 0 && endptr > str && start <= end &&
-                    (start > INT64_MAX - 65536 ||
-                     end < start + 65536)) {
-                    if (*endptr == '\0') {
-                        cur = g_malloc0(sizeof(*cur));
-                        range_set_bounds(cur, start, end);
-                        siv->ranges = range_list_insert(siv->ranges, cur);
-                        cur = NULL;
-                        str = NULL;
-                    } else if (*endptr == ',') {
-                        str = endptr + 1;
-                        cur = g_malloc0(sizeof(*cur));
-                        range_set_bounds(cur, start, end);
-                        siv->ranges = range_list_insert(siv->ranges, cur);
-                        cur = NULL;
-                    } else {
-                        goto error;
-                    }
-                } else {
-                    goto error;
-                }
-            } else if (*endptr == ',') {
-                str = endptr + 1;
-                cur = g_malloc0(sizeof(*cur));
-                range_set_bounds(cur, start, start);
-                siv->ranges = range_list_insert(siv->ranges, cur);
-                cur = NULL;
-            } else {
-                goto error;
-            }
-        } else {
-            goto error;
-        }
-    } while (str);
-
-    return 0;
-error:
-    g_list_foreach(siv->ranges, free_range, NULL);
-    g_list_free(siv->ranges);
-    siv->ranges = NULL;
-    error_setg(errp, QERR_INVALID_PARAMETER_VALUE, name ? name : "null",
-               "an int64 value or range");
-    return -1;
-}
-
-static void
-start_list(Visitor *v, const char *name, GenericList **list, size_t size,
-           Error **errp)
+static void start_list(Visitor *v, const char *name, GenericList **list,
+                       size_t size, Error **errp)
 {
     StringInputVisitor *siv = to_siv(v);
 
-    /* We don't support visits without a list */
-    assert(list);
+    assert(siv->lm == LM_NONE);
     siv->list = list;
+    siv->unparsed_string = siv->string;
 
-    if (parse_str(siv, name, errp) < 0) {
-        *list = NULL;
-        return;
-    }
-
-    siv->cur_range = g_list_first(siv->ranges);
-    if (siv->cur_range) {
-        Range *r = siv->cur_range->data;
-        if (r) {
-            siv->cur = range_lob(r);
+    if (!siv->string[0]) {
+        if (list) {
+            *list = NULL;
         }
-        *list = g_malloc0(size);
+        siv->lm = LM_END;
     } else {
-        *list = NULL;
+        if (list) {
+            *list = g_malloc0(size);
+        }
+        siv->lm = LM_UNPARSED;
     }
 }
 
 static GenericList *next_list(Visitor *v, GenericList *tail, size_t size)
 {
     StringInputVisitor *siv = to_siv(v);
-    Range *r;
-
-    if (!siv->ranges || !siv->cur_range) {
-        return NULL;
-    }
 
-    r = siv->cur_range->data;
-    if (!r) {
+    switch (siv->lm) {
+    case LM_END:
         return NULL;
-    }
-
-    if (!range_contains(r, siv->cur)) {
-        siv->cur_range = g_list_next(siv->cur_range);
-        if (!siv->cur_range) {
-            return NULL;
-        }
-        r = siv->cur_range->data;
-        if (!r) {
-            return NULL;
-        }
-        siv->cur = range_lob(r);
+    case LM_INT64_RANGE:
+    case LM_UINT64_RANGE:
+    case LM_UNPARSED:
+        /* we have an unparsed string or something left in a range */
+        break;
+    default:
+        abort();
     }
 
     tail->next = g_malloc0(size);
@@ -179,88 +106,208 @@ static GenericList *next_list(Visitor *v, GenericList *tail, size_t size)
 static void check_list(Visitor *v, Error **errp)
 {
     const StringInputVisitor *siv = to_siv(v);
-    Range *r;
-    GList *cur_range;
 
-    if (!siv->ranges || !siv->cur_range) {
+    switch (siv->lm) {
+    case LM_INT64_RANGE:
+    case LM_UINT64_RANGE:
+    case LM_UNPARSED:
+        error_setg(errp, "Fewer list elements expected");
         return;
-    }
-
-    r = siv->cur_range->data;
-    if (!r) {
+    case LM_END:
         return;
+    default:
+        abort();
     }
-
-    if (!range_contains(r, siv->cur)) {
-        cur_range = g_list_next(siv->cur_range);
-        if (!cur_range) {
-            return;
-        }
-        r = cur_range->data;
-        if (!r) {
-            return;
-        }
-    }
-
-    error_setg(errp, "Range contains too many values");
 }
 
 static void end_list(Visitor *v, void **obj)
 {
     StringInputVisitor *siv = to_siv(v);
 
+    assert(siv->lm != LM_NONE);
     assert(siv->list == obj);
+    siv->list = NULL;
+    siv->unparsed_string = NULL;
+    siv->lm = LM_NONE;
+}
+
+static int try_parse_int64_list_entry(StringInputVisitor *siv, int64_t *obj)
+{
+    const char *endptr;
+    int64_t start, end;
+
+    /* parse a simple int64 or range */
+    if (qemu_strtoi64(siv->unparsed_string, &endptr, 0, &start)) {
+        return -EINVAL;
+    }
+    end = start;
+
+    switch (endptr[0]) {
+    case '\0':
+        siv->unparsed_string = endptr;
+        break;
+    case ',':
+        siv->unparsed_string = endptr + 1;
+        break;
+    case '-':
+        /* parse the end of the range */
+        if (qemu_strtoi64(endptr + 1, &endptr, 0, &end)) {
+            return -EINVAL;
+        }
+        if (start > end || end - start >= RANGE_MAX_ELEMENTS) {
+            return -EINVAL;
+        }
+        switch (endptr[0]) {
+        case '\0':
+            siv->unparsed_string = endptr;
+            break;
+        case ',':
+            siv->unparsed_string = endptr + 1;
+            break;
+        default:
+            return -EINVAL;
+        }
+        break;
+    default:
+        return -EINVAL;
+    }
+
+    /* we have a proper range (with maybe only one element) */
+    siv->lm = LM_INT64_RANGE;
+    siv->rangeNext.i64 = start;
+    siv->rangeEnd.i64 = end;
+    return 0;
 }
 
 static void parse_type_int64(Visitor *v, const char *name, int64_t *obj,
                              Error **errp)
 {
     StringInputVisitor *siv = to_siv(v);
-
-    if (parse_str(siv, name, errp) < 0) {
+    int64_t val;
+
+    switch (siv->lm) {
+    case LM_NONE:
+        /* just parse a simple int64, bail out if not completely consumed */
+        if (qemu_strtoi64(siv->string, NULL, 0, &val)) {
+                error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
+                           name ? name : "null", "int64");
+            return;
+        }
+        *obj = val;
         return;
+    case LM_UNPARSED:
+        if (try_parse_int64_list_entry(siv, obj)) {
+            error_setg(errp, QERR_INVALID_PARAMETER_VALUE, name ? name : "null",
+                       "list of int64 values or ranges");
+            return;
+        }
+        assert(siv->lm == LM_INT64_RANGE);
+        /* fall through */
+    case LM_INT64_RANGE:
+        /* return the next element in the range */
+        assert(siv->rangeNext.i64 <= siv->rangeEnd.i64);
+        *obj = siv->rangeNext.i64++;
+
+        if (siv->rangeNext.i64 > siv->rangeEnd.i64 || *obj == INT64_MAX) {
+            /* end of range, check if there is more to parse */
+            siv->lm = siv->unparsed_string[0] ? LM_UNPARSED : LM_END;
+        }
+        return;
+    case LM_END:
+        error_setg(errp, "Fewer list elements expected");
+        return;
+    default:
+        abort();
     }
+}
 
-    if (!siv->ranges) {
-        goto error;
-    }
-
-    if (!siv->cur_range) {
-        Range *r;
+static int try_parse_uint64_list_entry(StringInputVisitor *siv, uint64_t *obj)
+{
+    const char *endptr;
+    uint64_t start, end;
 
-        siv->cur_range = g_list_first(siv->ranges);
-        if (!siv->cur_range) {
-            goto error;
+    /* parse a simple uint64 or range */
+    if (qemu_strtou64(siv->unparsed_string, &endptr, 0, &start)) {
+        return -EINVAL;
+    }
+    end = start;
+
+    switch (endptr[0]) {
+    case '\0':
+        siv->unparsed_string = endptr;
+        break;
+    case ',':
+        siv->unparsed_string = endptr + 1;
+        break;
+    case '-':
+        /* parse the end of the range */
+        if (qemu_strtou64(endptr + 1, &endptr, 0, &end)) {
+            return -EINVAL;
         }
-
-        r = siv->cur_range->data;
-        if (!r) {
-            goto error;
+        if (start > end || end - start >= RANGE_MAX_ELEMENTS) {
+            return -EINVAL;
         }
-
-        siv->cur = range_lob(r);
+        switch (endptr[0]) {
+        case '\0':
+            siv->unparsed_string = endptr;
+            break;
+        case ',':
+            siv->unparsed_string = endptr + 1;
+            break;
+        default:
+            return -EINVAL;
+        }
+        break;
+    default:
+        return -EINVAL;
     }
 
-    *obj = siv->cur;
-    siv->cur++;
-    return;
-
-error:
-    error_setg(errp, QERR_INVALID_PARAMETER_VALUE, name ? name : "null",
-               "an int64 value or range");
+    /* we have a proper range (with maybe only one element) */
+    siv->lm = LM_UINT64_RANGE;
+    siv->rangeNext.u64 = start;
+    siv->rangeEnd.u64 = end;
+    return 0;
 }
 
 static void parse_type_uint64(Visitor *v, const char *name, uint64_t *obj,
                               Error **errp)
 {
-    /* FIXME: parse_type_int64 mishandles values over INT64_MAX */
-    int64_t i;
-    Error *err = NULL;
-    parse_type_int64(v, name, &i, &err);
-    if (err) {
-        error_propagate(errp, err);
-    } else {
-        *obj = i;
+    StringInputVisitor *siv = to_siv(v);
+    uint64_t val;
+
+    switch (siv->lm) {
+    case LM_NONE:
+        /* just parse a simple uint64, bail out if not completely consumed */
+        if (qemu_strtou64(siv->string, NULL, 0, &val)) {
+            error_setg(errp, QERR_INVALID_PARAMETER_VALUE, name ? name : "null",
+                       "uint64");
+            return;
+        }
+        *obj = val;
+        return;
+    case LM_UNPARSED:
+        if (try_parse_uint64_list_entry(siv, obj)) {
+            error_setg(errp, QERR_INVALID_PARAMETER_VALUE, name ? name : "null",
+                       "list of uint64 values or ranges");
+            return;
+        }
+        assert(siv->lm == LM_UINT64_RANGE);
+        /* fall through */
+    case LM_UINT64_RANGE:
+        /* return the next element in the range */
+        assert(siv->rangeNext.u64 <= siv->rangeEnd.u64);
+        *obj = siv->rangeNext.u64++;
+
+        if (siv->rangeNext.u64 > siv->rangeEnd.u64 || *obj == UINT64_MAX) {
+            /* end of range, check if there is more to parse */
+            siv->lm = siv->unparsed_string[0] ? LM_UNPARSED : LM_END;
+        }
+        return;
+    case LM_END:
+        error_setg(errp, "Fewer list elements expected");
+        return;
+    default:
+        abort();
     }
 }
 
@@ -271,6 +318,7 @@ static void parse_type_size(Visitor *v, const char *name, uint64_t *obj,
     Error *err = NULL;
     uint64_t val;
 
+    assert(siv->lm == LM_NONE);
     parse_option_size(name, siv->string, &val, &err);
     if (err) {
         error_propagate(errp, err);
@@ -285,6 +333,7 @@ static void parse_type_bool(Visitor *v, const char *name, bool *obj,
 {
     StringInputVisitor *siv = to_siv(v);
 
+    assert(siv->lm == LM_NONE);
     if (!strcasecmp(siv->string, "on") ||
         !strcasecmp(siv->string, "yes") ||
         !strcasecmp(siv->string, "true")) {
@@ -307,6 +356,7 @@ static void parse_type_str(Visitor *v, const char *name, char **obj,
 {
     StringInputVisitor *siv = to_siv(v);
 
+    assert(siv->lm == LM_NONE);
     *obj = g_strdup(siv->string);
 }
 
@@ -316,6 +366,7 @@ static void parse_type_number(Visitor *v, const char *name, double *obj,
     StringInputVisitor *siv = to_siv(v);
     double val;
 
+    assert(siv->lm == LM_NONE);
     if (qemu_strtod_finite(siv->string, NULL, &val)) {
         error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
                    "number");
@@ -330,9 +381,10 @@ static void parse_type_null(Visitor *v, const char *name, QNull **obj,
 {
     StringInputVisitor *siv = to_siv(v);
 
+    assert(siv->lm == LM_NONE);
     *obj = NULL;
 
-    if (!siv->string || siv->string[0]) {
+    if (siv->string[0]) {
         error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
                    "null");
         return;
@@ -345,8 +397,6 @@ static void string_input_free(Visitor *v)
 {
     StringInputVisitor *siv = to_siv(v);
 
-    g_list_foreach(siv->ranges, free_range, NULL);
-    g_list_free(siv->ranges);
     g_free(siv);
 }
 
@@ -372,5 +422,6 @@ Visitor *string_input_visitor_new(const char *str)
     v->visitor.free = string_input_free;
 
     v->string = str;
+    v->lm = LM_NONE;
     return &v->visitor;
 }