Merge pull request #1269 from TheWitness/master

Fix #1268 - Segmentation Fault with Constant Lines
oetiker · Nov 17, 2024 · 637ad23 · 637ad23
2 parents 5041750 + 250d939
commit 637ad23
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Showing 2 changed files with 40 additions and 13 deletions.
diff --git a/CHANGES b/CHANGES
@@ -6,6 +6,7 @@ Bugfixes
 * Fix MacOS Build error (no SOCK_CLOEXEC on mac) @ensc fixes oetiker#1261
 * Fix build on 32bits platforms (like armhf) when time_t is 64bits, fixes #1264
 * Fix compilation on illumos @hadfl
+* Fix issue where RRDtool detects a LINE or AREA with a constant numeric value as being exportable
 
 Features
 --------

diff --git a/src/rrd_xport.c b/src/rrd_xport.c
@@ -21,6 +21,8 @@
 #include "rrd_snprintf.h"
 #include "compat-cloexec.h"
 
+int is_numeric(char *);
+
 static int rrd_xport_fn(
     image_desc_t *,
     time_t *,
@@ -239,7 +241,21 @@ int rrd_xport(
     return 0;
 }
 
+int is_numeric(char *instring) {
+    int c = 0;
+
+    if (*instring != '-' && *instring != '.' && !isdigit(*instring)) {
+        return 0;
+    }
+
+    if (strspn(instring+1, "0123456789.") < strlen(instring+1)) {
+        return 0;
+    }
+
+    while (*instring) if (*instring++ == '.') if (++c > 1) return 0;
 
+    return 1;
+}
 
 static int rrd_xport_fn(
     image_desc_t *im,
@@ -280,15 +296,22 @@ static int rrd_xport_fn(
         case GF_LINE:
         case GF_AREA:
         case GF_STACK:
-            (*col_cnt) += dolines;
+            /* only count the gf if it's numeric otherwise it's a constant line */
+            if (!is_numeric(im->gdes[i].vname)) {
+                (*col_cnt) += dolines;
+            }
             break;
         case GF_XPORT:
-            (*col_cnt)++;
+            /* only count the gf if it's numeric otherwise it's a constant line */
+            if (!is_numeric(im->gdes[i].vname)) {
+                (*col_cnt)++;
+            }
             break;
         default:
             break;
         }
     }
+
     if ((*col_cnt) == 0) {
         rrd_set_error("no XPORT found, nothing to do");
         return -1;
@@ -319,10 +342,14 @@ static int rrd_xport_fn(
         case GF_LINE:
         case GF_AREA:
         case GF_STACK:
-            handle = dolines;
+            if (!is_numeric(im->gdes[i].vname)) {
+                handle = dolines;
+            }
             break;
         case GF_XPORT:
-            handle = 1;
+            if (!is_numeric(im->gdes[i].vname)) {
+                handle = 1;
+            }
             break;
         default:
             handle = 0;
@@ -380,20 +407,19 @@ static int rrd_xport_fn(
     }
     dstptr = (*data);
 
+	long unsigned int chosen_idx  = 0;
+
     /* fill data structure */
     for (dst_row = 0; (int) dst_row < (int) row_cnt; dst_row++) {
         for (i = 0; i < (int) (*col_cnt); i++) {
-            long      vidx = im->gdes[ref_list[i]].vidx;
-            time_t    now = *start + dst_row * *step;
+            long       vidx = im->gdes[ref_list[i]].vidx;
+            time_t     now = *start + dst_row * *step;
 
-            (*dstptr++) = im->gdes[vidx].data[(unsigned long)
-                                              floor((double)
-                                                    (now -
-                                                     im->gdes[vidx].start)
-                                                    / im->gdes[vidx].step)
-                                              * im->gdes[vidx].ds_cnt +
-                                              im->gdes[vidx].ds];
+            if (im->gdes[vidx].step > 0) {
+                chosen_idx = floor((double) (now - im->gdes[vidx].start) / im->gdes[vidx].step) * im->gdes[vidx].ds_cnt + im->gdes[vidx].ds;
 
+                (*dstptr++) = im->gdes[vidx].data[chosen_idx];
+            }
         }
     }