patch 9.0.2141: [security]: buffer-overflow in suggest_trie_walk
Problem: [security]: buffer-overflow in suggest_trie_walk
Solution: Check n before using it as index into byts array
Basically, n as an index into the byts array, can point to beyond the byts
array. So let's double check, that n is within the expected range after
incrementing it from sp->ts_curi and bail out if it would be invalid.
Reported by @henices, thanks!
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/spellsuggest.c b/src/spellsuggest.c
index e1c303a..ecc0a74 100644
--- a/src/spellsuggest.c
+++ b/src/spellsuggest.c
@@ -2175,6 +2175,13 @@
// - Skip the byte if it's equal to the byte in the word,
// accepting that byte is always better.
n += sp->ts_curi++;
+
+ // break out, if we would be accessing byts buffer out of bounds
+ if (byts == slang->sl_fbyts && n >= slang->sl_fbyts_len)
+ {
+ got_int = TRUE;
+ break;
+ }
c = byts[n];
if (soundfold && sp->ts_twordlen == 0 && c == '*')
// Inserting a vowel at the start of a word counts less,