ustream: prevent recursive calls to the read callback

[project/libubox.git] / blobmsg.c

diff --git a/blobmsg.c b/blobmsg.c
index 48dba8156d58ffe60af2604e59250b8a8e3cf4c9..d87d60728fcdd89c6df32a2c818b1a2325c7ce81 100644 (file)
--- a/blobmsg.c
+++ b/blobmsg.c
@@ -30,43 +30,31 @@ bool blobmsg_check_attr(const struct blob_attr *attr, bool name)
        return blobmsg_check_attr_len(attr, name, blob_raw_len(attr));
 }
 
-static bool blobmsg_check_name(const struct blob_attr *attr, size_t len, bool name)
+static bool blobmsg_check_name(const struct blob_attr *attr, bool name)
 {
-       char *limit = (char *) attr + len;
        const struct blobmsg_hdr *hdr;
+       uint16_t namelen;
 
-       hdr = blob_data(attr);
-       if (name && !hdr->namelen)
+       if (!blob_is_extended(attr))
+               return !name;
+
+       if (blob_len(attr) < sizeof(struct blobmsg_hdr))
                return false;
 
-       if ((char *) hdr->name + blobmsg_namelen(hdr) > limit)
+       hdr = (const struct blobmsg_hdr *)blob_data(attr);
+       if (name && !hdr->namelen)
                return false;
 
-       if (blobmsg_namelen(hdr) > (blob_len(attr) - sizeof(struct blobmsg_hdr)))
+       namelen = blobmsg_namelen(hdr);
+       if (blob_len(attr) < (size_t)blobmsg_hdrlen(namelen))
                return false;
 
-       if (hdr->name[blobmsg_namelen(hdr)] != 0)
+       if (hdr->name[namelen] != 0)
                return false;
 
        return true;
 }
 
-static const char* blobmsg_check_data(const struct blob_attr *attr, size_t len, size_t *data_len)
-{
-       char *limit = (char *) attr + len;
-       const char *data;
-
-       *data_len = blobmsg_data_len(attr);
-       if (*data_len > blob_raw_len(attr))
-               return NULL;
-
-       data = blobmsg_data(attr);
-       if (data + *data_len > limit)
-               return NULL;
-
-       return data;
-}
-
 bool blobmsg_check_attr_len(const struct blob_attr *attr, bool name, size_t len)
 {
        const char *data;
@@ -76,7 +64,11 @@ bool blobmsg_check_attr_len(const struct blob_attr *attr, bool name, size_t len)
        if (len < sizeof(struct blob_attr))
                return false;
 
-       if (!blobmsg_check_name(attr, len, name))
+       data_len = blob_raw_len(attr);
+       if (data_len < sizeof(struct blob_attr) || data_len > len)
+               return false;
+
+       if (!blobmsg_check_name(attr, name))
                return false;
 
        id = blob_id(attr);
@@ -86,9 +78,8 @@ bool blobmsg_check_attr_len(const struct blob_attr *attr, bool name, size_t len)
        if (!blob_type[id])
                return true;
 
-       data = blobmsg_check_data(attr, len, &data_len);
-       if (!data)
-               return false;
+       data = blobmsg_data(attr);
+       data_len = blobmsg_data_len(attr);
 
        return blob_check_type(data, data_len, blob_type[id]);
 }
@@ -98,16 +89,18 @@ int blobmsg_check_array(const struct blob_attr *attr, int type)
        return blobmsg_check_array_len(attr, type, blob_raw_len(attr));
 }
 
-int blobmsg_check_array_len(const struct blob_attr *attr, int type, size_t len)
+int blobmsg_check_array_len(const struct blob_attr *attr, int type,
+                           size_t blob_len)
 {
        struct blob_attr *cur;
+       size_t rem;
        bool name;
        int size = 0;
 
        if (type > BLOBMSG_TYPE_LAST)
                return -1;
 
-       if (!blobmsg_check_attr_len(attr, false, len))
+       if (!blobmsg_check_attr_len(attr, false, blob_len))
                return -1;
 
        switch (blobmsg_type(attr)) {
@@ -121,11 +114,11 @@ int blobmsg_check_array_len(const struct blob_attr *attr, int type, size_t len)
                return -1;
        }
 
-       __blobmsg_for_each_attr(cur, attr, len) {
+       blobmsg_for_each_attr(cur, attr, rem) {
                if (type != BLOBMSG_TYPE_UNSPEC && blobmsg_type(cur) != type)
                        return -1;
 
-               if (!blobmsg_check_attr_len(cur, name, len))
+               if (!blobmsg_check_attr_len(cur, name, rem))
                        return -1;
 
                size++;
@@ -170,11 +163,10 @@ int blobmsg_parse_array(const struct blobmsg_policy *policy, int policy_len,
        return 0;
 }
 
-
 int blobmsg_parse(const struct blobmsg_policy *policy, int policy_len,
                   struct blob_attr **tb, void *data, unsigned int len)
 {
-       struct blobmsg_hdr *hdr;
+       const struct blobmsg_hdr *hdr;
        struct blob_attr *attr;
        uint8_t *pslen;
        int i;
@@ -191,20 +183,31 @@ int blobmsg_parse(const struct blobmsg_policy *policy, int policy_len,
        }
 
        __blob_for_each_attr(attr, data, len) {
+               if (!blobmsg_check_attr_len(attr, false, len))
+                       return -1;
+
+               if (!blob_is_extended(attr))
+                       continue;
+
                hdr = blob_data(attr);
                for (i = 0; i < policy_len; i++) {
                        if (!policy[i].name)
                                continue;
 
                        if (policy[i].type != BLOBMSG_TYPE_UNSPEC &&
+                           policy[i].type != BLOBMSG_CAST_INT64 &&
                            blob_id(attr) != policy[i].type)
                                continue;
 
-                       if (blobmsg_namelen(hdr) != pslen[i])
+                       if (policy[i].type == BLOBMSG_CAST_INT64 &&
+                           (blob_id(attr) != BLOBMSG_TYPE_INT64 &&
+                            blob_id(attr) != BLOBMSG_TYPE_INT32 &&
+                            blob_id(attr) != BLOBMSG_TYPE_INT16 &&
+                            blob_id(attr) != BLOBMSG_TYPE_INT8))
                                continue;
 
-                       if (!blobmsg_check_attr_len(attr, true, len))
-                               return -1;
+                       if (blobmsg_namelen(hdr) != pslen[i])
+                               continue;
 
                        if (tb[i])
                                continue;
@@ -240,7 +243,10 @@ blobmsg_new(struct blob_buf *buf, int type, const char *name, int payload_len, v
        attr->id_len |= be32_to_cpu(BLOB_ATTR_EXTENDED);
        hdr = blob_data(attr);
        hdr->namelen = cpu_to_be16(namelen);
-       strcpy((char *) hdr->name, (const char *)name);
+
+       memcpy(hdr->name, name, namelen);
+       hdr->name[namelen] = '\0';
+
        pad_end = *data = blobmsg_data(attr);
        pad_start = (char *) &hdr->name[namelen];
        if (pad_start < pad_end)
@@ -287,10 +293,17 @@ int blobmsg_vprintf(struct blob_buf *buf, const char *name, const char *format,
        len = vsnprintf(&cbuf, sizeof(cbuf), format, arg2);
        va_end(arg2);
 
-       sbuf = blobmsg_alloc_string_buffer(buf, name, len + 1);
+       if (len < 0)
+               return -1;
+
+       sbuf = blobmsg_alloc_string_buffer(buf, name, len);
        if (!sbuf)
                return -1;
-       ret = vsprintf(sbuf, format, arg);
+
+       ret = vsnprintf(sbuf, len + 1, format, arg);
+       if (ret < 0)
+               return -1;
+
        blobmsg_add_string_buffer(buf);
 
        return ret;
@@ -315,6 +328,7 @@ blobmsg_alloc_string_buffer(struct blob_buf *buf, const char *name, unsigned int
        struct blob_attr *attr;
        void *data_dest;
 
+       maxlen++;
        attr = blobmsg_new(buf, BLOBMSG_TYPE_STRING, name, maxlen, &data_dest);
        if (!attr)
                return NULL;
@@ -330,7 +344,7 @@ blobmsg_realloc_string_buffer(struct blob_buf *buf, unsigned int maxlen)
 {
        struct blob_attr *attr = blob_next(buf->head);
        int offset = attr_to_offset(buf, blob_next(buf->head)) + blob_pad_len(attr) - BLOB_COOKIE;
-       int required = maxlen - (buf->buflen - offset);
+       int required = maxlen + 1 - (buf->buflen - offset);
 
        if (required <= 0)
                goto out;