Revert "bb#11267 - libclamav upx guard against signed overflows"

...causing false negatives in regression runs.

This reverts commit ca57cc3c0c.

libclamav/upx.c

@@ -317,8 +317,6 @@ int upx_inflate2b(const char *src, uint32_t ssize, char *dst, uint32_t *dsize, u
     while (1) {
       if ( (oob = doubleebx(src, &myebx, &scur, ssize)) == -1 )
         return -1;
-      if (backbytes >= (INT_MAX / 2) + oob)
-	      return -1;
       backbytes = backbytes*2+oob;
       if ( (oob = doubleebx(src, &myebx, &scur, ssize)) == -1 )
 	return -1;
@@ -394,8 +392,6 @@ int upx_inflate2d(const char *src, uint32_t ssize, char *dst, uint32_t *dsize, u
     while (1) {
       if ( (oob = doubleebx(src, &myebx, &scur, ssize)) == -1 )
         return -1;
-      if (backbytes >= (INT_MAX / 2) + oob)
-	      return -1;
       backbytes = backbytes*2+oob;
       if ( (oob = doubleebx(src, &myebx, &scur, ssize)) == -1 )
         return -1;
@@ -404,8 +400,6 @@ int upx_inflate2d(const char *src, uint32_t ssize, char *dst, uint32_t *dsize, u
       backbytes--;
       if ( (oob = doubleebx(src, &myebx, &scur, ssize)) == -1 )
         return -1;
-      if (backbytes >= (INT_MAX / 2) + oob)
-	      return -1;
       backbytes=backbytes*2+oob;
     }
 
@@ -479,8 +473,6 @@ int upx_inflate2e(const char *src, uint32_t ssize, char *dst, uint32_t *dsize, u
     for(;;) {
       if ( (oob = doubleebx(src, &myebx, &scur, ssize)) == -1 )
         return -1;
-      if (backbytes >= (INT_MAX / 2) + oob)
-	      return -1;
       backbytes = backbytes*2+oob;
       if ( (oob = doubleebx(src, &myebx, &scur, ssize)) == -1 )
         return -1;
@@ -489,8 +481,6 @@ int upx_inflate2e(const char *src, uint32_t ssize, char *dst, uint32_t *dsize, u
       backbytes--;
       if ( (oob = doubleebx(src, &myebx, &scur, ssize)) == -1 )
         return -1;
-      if (backbytes >= (INT_MAX / 2) + oob)
-	      return -1;
       backbytes=backbytes*2+oob;
     }