There's a shift by (hash_shift - 12) in hash(), but hash() is called with hash_shift=10, resulting in a negative shift and thus undefined behavior. A simple and stupid minimal fix is to just change the subtracted amount to 10. Caught by clang -fsanitize=undefined. Signed-off-by: Sami Liedes <sami.liedes@xxxxxx> --- e2fsck/revoke.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/e2fsck/revoke.c b/e2fsck/revoke.c index 38c265e..dddef4d 100644 --- a/e2fsck/revoke.c +++ b/e2fsck/revoke.c @@ -115,7 +115,7 @@ static inline int hash(journal_t *journal, unsigned long block) return ((block << (hash_shift - 6)) ^ (block >> 13) ^ - (block << (hash_shift - 12))) & (table->hash_size - 1); + (block << (hash_shift - 10))) & (table->hash_size - 1); } static int insert_revoke_hash(journal_t *journal, unsigned long blocknr, -- 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html