Changeset 47d4f8c

Timestamp:

06/27/18 18:01:48 (3 years ago)

Author:

Shane Alcock <salcock@…>

Branches:

cachetimestamps, develop, master, rc-4.0.4, ringdecrementfix, ringperformance

Children:

1ed69dc

Parents:

35de364

Message:

Fix various string truncation/overflow warnings

Thanks gcc 8!

Files:

• lib/format_linux_common.c (modified) (1 diff)
• lib/libtrace.h.in (modified) (1 diff)
• lib/trace.c (modified) (3 diffs)
• libpacketdump/eth_2054.c (modified) (4 diffs)
• tools/tracereport/misc_report.c (modified) (1 diff)
• tools/tracesplit/tracesplit.c (modified) (1 diff)

lib/format_linux_common.c

@@ -87 +87 @@
                 sock = socket(PF_INET, SOCK_STREAM, 0);
                 memset(&ifr, 0, sizeof(struct ifreq));
-                strncpy(ifr.ifr_name, libtrace->uridata, IF_NAMESIZE);
+                strncpy(ifr.ifr_name, libtrace->uridata, IF_NAMESIZE - 1);
                 if (ioctl(sock, SIOCGIFHWADDR, &ifr) != 0) {
                         perror("Can't get HWADDR for interface");

lib/libtrace.h.in

@@ -277 +277 @@
 typedef struct trace_err_t{
         int err_num;            /**< error code */
-        char problem[255];      /**< the format, uri etc that caused the error for reporting purposes */
+        char problem[1024];     /**< the format, uri etc that caused the error for reporting purposes */
 } libtrace_err_t;
 

lib/trace.c

@@ -107 +107 @@
  * will use our own one that does
  */
-static void xstrncpy(char *dest, const char *src, size_t n)
-{
-        strncpy(dest,src,n);
-        dest[n]='\0';
+static inline void xstrncpy(char *dest, const char *src, size_t n,
+                size_t destlen)
+{
+        size_t slen = destlen - 1;
+        if (n < slen) {
+                slen = n;
+        }
+        strncpy(dest,src,slen);
+        dest[slen]='\0';
 }
 
@@ -120 +125 @@
                 exit(EXIT_FAILURE);
         }
-        xstrncpy(ret,src,n);
+        xstrncpy(ret,src,n,n+1);
         return ret;
 }
@@ -371 +376 @@
 
         if((uridata = strchr(uri,':')) == NULL) {
-                xstrncpy(scan, uri, strlen(uri));
+                xstrncpy(scan, uri, strlen(uri), URI_PROTO_LINE);
         } else {
-                xstrncpy(scan,uri, (size_t)(uridata - uri));
+                xstrncpy(scan,uri, (size_t)(uridata - uri), URI_PROTO_LINE);
         }
 

libpacketdump/eth_2054.c

@@ -47 +47 @@
 static char *format_hrd(const struct arphdr *arp, const char *hrd) {
         static char buffer[1024] = {0,};
-        int i;
+        int i, ret;
+        size_t bufused;
 
         if (!hrd) {
@@ -59 +60 @@
                         break;
                 default:
+                        bufused = 0;
                         for (i=0;i<arp->ar_hln;i++) {
-                                snprintf(buffer,sizeof(buffer),"%s %02x",
-                                                buffer,(unsigned char)hrd[i]);
+                                if (bufused >= sizeof(buffer)) {
+                                        break;
+                                }
+                                ret = snprintf(buffer + bufused,
+                                                sizeof(buffer) - bufused,
+                                                "%02x ",
+                                                (unsigned char)hrd[i]);
+                                if (ret > 0) {
+                                        bufused += ret;
+                                }
                         }
                         break;
@@ -77 +87 @@
 static char *format_pro(const struct arphdr *arp, const char *pro) {
         static char buffer[1024] = {0,};
-        int i;
+        int i, ret;
+        size_t bufused;
         
         if (!pro) {
@@ -91 +102 @@
                 default:
                         snprintf(buffer, sizeof(buffer), "%s", " (");
+                        bufused = 2;
                         for (i=0;i<arp->ar_pln;i++) {
-                                snprintf(buffer,sizeof(buffer),"%s %02x",
-                                                buffer,(unsigned char)pro[i]);
+                                if (bufused >= sizeof(buffer)) {
+                                        break;
+                                }
+                                ret = snprintf(buffer + bufused,
+                                                sizeof(buffer) - bufused,
+                                                "%02x ",
+                                                (unsigned char)pro[i]);
+                                if (ret > 0) {
+                                        bufused += ret;
+                                }
                         }
-                        strncat(buffer,")",sizeof(buffer) - strlen(buffer) - 1);
+                        if (bufused < sizeof(buffer)) {
+                                snprintf(buffer + bufused,
+                                                sizeof(buffer) - bufused,
+                                                ")");
+                        }
                         break;
         }

tools/tracereport/misc_report.c

@@ -67 +67 @@
 {
         static char ret[1024];
-        char tmp[1024];
+        char tmp[128];
         ret[0]='\0';
         if (ts == 0) 

tools/tracesplit/tracesplit.c

@@ -61 +61 @@
 static char *strdupcat(char *str,char *app)
 {
-        str=realloc(str,strlen(str)+strlen(app)+1);
-        strncat(str,app,strlen(str) + strlen(app));
+        int newsize = strlen(str)+strlen(app)+1;
+        str=realloc(str,newsize);
+        strncat(str,app,newsize - strlen(str) - 1);
         return str;
 }