ui-ssdiff.c: correct length check for LCS table

Each individual string may be too long for its respective
dimension of the LCS table.

Signed-off-by: Eric Wong <normalperson@yhbt.net>

1 files changed, 2 insertions, 4 deletions

@@ -42,14 +42,12 @@ static char *longest_common_subsequence(char *A, char *B)
         int i, j, ri;
         int m = strlen(A);
         int n = strlen(B);
-        int tmp1, tmp2, length;
+        int tmp1, tmp2;
         int lcs_length;
         char *result;
 
-        length = (m + 1) * (n + 1);
-
         // We bail if the lines are too long
-        if (length > MAX_SSDIFF_SIZE)
+        if (m >= MAX_SSDIFF_M || n >= MAX_SSDIFF_N)
                 return NULL;
 
         create_or_reset_lcs_table();