[PATCH] pack-bitmap: do not core dump
- From
Kyle J. McKay <mackyle@gmail.com>
- Date
- Apr 22, 2014, 22:53 UTC
- Message-ID
- <781073ea08e86301f62e708bc0b80fd@74d39fa044aa309eaea14b9f57fe79c>
So I was trying to use pack.writebitmaps=true and all I got was core dumps.
The fix with a real subject line ;) is below. I think perhaps this should be picked up for the 2.0.0 release. (Patch is against master.)
--Kyle
---- >8 ---- Subject: [PATCH] ewah_bitmap.c: do not assume size_t and eword_t are the same size
When buffer_grow changes the size of the buffer using realloc, it first computes and saves the rlw pointer's offset into the buffer using (uint8_t *) math before the realloc but then restores it using (eword_t *) math.
In order to do this it's necessary to convert the (uint8_t *) offset into an (eword_t *) offset. It was doing this by dividing by the sizeof(size_t). Unfortunately sizeof(size_t) is not same as sizeof(eword_t) on all platforms.
This causes illegal memory accesses and other bad things to happen when attempting to use bitmaps on those platforms.
Fix this by dividing by the sizeof(eword_t) instead which will always be correct for all platforms.
Signed-off-by: Kyle J. McKay <mackyle@gmail.com> --- ewah/ewah_bitmap.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/ewah/ewah_bitmap.c b/ewah/ewah_bitmap.c index 9ced2dad..fccb42b5 100644 --- a/ewah/ewah_bitmap.c +++ b/ewah/ewah_bitmap.c @@ -41,7 +41,7 @@ static inline void buffer_grow(struct ewah_bitmap *self, size_t new_size) self->alloc_size = new_size; self->buffer = ewah_realloc(self->buffer, self->alloc_size * sizeof(eword_t)); - self->rlw = self->buffer + (rlw_offset / sizeof(size_t)); + self->rlw = self->buffer + (rlw_offset / sizeof(eword_t)); } static inline void buffer_push(struct ewah_bitmap *self, eword_t value)
-- 1.8.5