patch 8.2.4247: stack corruption when looking for spell suggestions
Problem: Stack corruption when looking for spell suggestions.
Solution: Prevent the depth increased too much. Add a five second time
limit to finding suggestions.
diff --git a/src/spellsuggest.c b/src/spellsuggest.c
index b2b4029..e54b6fd 100644
--- a/src/spellsuggest.c
+++ b/src/spellsuggest.c
@@ -1205,7 +1205,7 @@
// Check the maximum score, if we go over it we won't try this change.
#define TRY_DEEPER(su, stack, depth, add) \
- (stack[depth].ts_score + (add) < su->su_maxscore)
+ (depth < MAXWLEN && stack[depth].ts_score + (add) < su->su_maxscore)
/*
* Try finding suggestions by adding/removing/swapping letters.
@@ -1277,6 +1277,9 @@
char_u changename[MAXWLEN][80];
#endif
int breakcheckcount = 1000;
+#ifdef FEAT_RELTIME
+ proftime_T time_limit;
+#endif
int compound_ok;
// Go through the whole case-fold tree, try changes at each node.
@@ -1321,6 +1324,11 @@
sp->ts_state = STATE_START;
}
}
+#ifdef FEAT_RELTIME
+ // The loop may take an indefinite amount of time. Break out after five
+ // sectonds. TODO: add an option for the time limit.
+ profile_setlimit(5000, &time_limit);
+#endif
// Loop to find all suggestions. At each round we either:
// - For the current state try one operation, advance "ts_curi",
@@ -1355,7 +1363,8 @@
// At end of a prefix or at start of prefixtree: check for
// following word.
- if (byts[arridx] == 0 || n == (int)STATE_NOPREFIX)
+ if (depth < MAXWLEN
+ && (byts[arridx] == 0 || n == (int)STATE_NOPREFIX))
{
// Set su->su_badflags to the caps type at this position.
// Use the caps type until here for the prefix itself.
@@ -2649,6 +2658,10 @@
{
ui_breakcheck();
breakcheckcount = 1000;
+#ifdef FEAT_RELTIME
+ if (profile_passed_limit(&time_limit))
+ got_int = TRUE;
+#endif
}
}
}