i.atcorr: fix out of bound access in trunca, os and iso (#4493)

* i.atcorr: fix out of bound access in trunca, os and iso In trunca(), under 2 if conditionals (if rumu[1] > 0.8 and rmu[1] > 0.94), k and kk values are set to -1 respectively. When these values are used to access an array, it leads to out of bound access, which is undefined behavior in c++. Similarly in os() and iso(), if `taup < h[i]` for all values, iplane would still be -1 and we would be accessing an array with this as an index, which is undefined behavior. In both cases, to avoid that, set that index to zero. This was found using cppcheck tool. Signed-off-by: Mohan Yelugoti <[email protected]> * Update imagery/i.atcorr/computations.cpp When plane layer couldn't be determined, throw out an error and exit. Co-authored-by: Markus Metz <[email protected]> * Update imagery/i.atcorr/computations.cpp When plane layer couldn't be determined, throw out an error and exit. Co-authored-by: Markus Metz <[email protected]> * Fix clang-format issues Signed-off-by: Mohan Yelugoti <[email protected]> --------- Signed-off-by: Mohan Yelugoti <[email protected]> Co-authored-by: Markus Metz <[email protected]>
OSGeo · Oct 18, 2024 · d788eee · d788eee
1 parent 3c67825
commit d788eee
Showing 1 changed file with 15 additions and 5 deletions.
diff --git a/imagery/i.atcorr/computations.cpp b/imagery/i.atcorr/computations.cpp
@@ -102,14 +102,14 @@ double trunca()
     for (i = 0; i < 83; i++) {
         if (rmu[i] > 0.8)
             break;
-        k = i - 1;
+        k = i;
     }
 
     int kk = 0;
     for (i = 0; i < 83; i++) {
         if (rmu[i] > 0.94)
             break;
-        kk = i - 1;
+        kk = i;
     }
 
     double aa =
@@ -118,7 +118,7 @@ double trunca()
     double x1 = (double)(log10(sixs_trunc.pha[kk]));
     double x2 = (double)acos(rmu[kk]);
 
-    for (i = kk + 1; i < 83; i++) {
+    for (i = kk; i < 83; i++) {
         double a;
         if (fabs(rmu[i] - 1) <= 1e-08)
             a = x1 - aa * x2;
@@ -445,9 +445,14 @@ void os(const double tamoy, const double trmoy, const double pizmoy,
         /* compute position of the plane layer */
         double taup = tap + trp;
         iplane = -1;
-        for (int i = 0; i <= ntp; i++)
+        for (int i = 0; i <= ntp; i++) {
             if (taup >= h[i])
                 iplane = i;
+        }
+        if (iplane == -1) {
+            G_fatal_error(
+                _("Position of the plane layer could not be determined"));
+        }
 
         /* update the layer from the end to the position to update if necessary
          */
@@ -1006,9 +1011,14 @@ void iso(const double tamoy, const double trmoy, const double pizmoy,
         /* compute position of the plane layer */
         double taup = tap + trp;
         iplane = -1;
-        for (int i = 0; i <= ntp; i++)
+        for (int i = 0; i <= ntp; i++) {
             if (taup >= h[i])
                 iplane = i;
+        }
+        if (iplane == -1) {
+            G_fatal_error(
+                _("Position of the plane layer could not be determined"));
+        }
 
         /* update the layer from the end to the position to update if necessary
          */