[PATCH] pack-bitmap: do not core dump

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



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@xxxxxxxxx>
---
 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

--
To unsubscribe from this list: send the line "unsubscribe git" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html




[Index of Archives]     [Linux Kernel Development]     [Gcc Help]     [IETF Annouce]     [DCCP]     [Netdev]     [Networking]     [Security]     [V4L]     [Bugtraq]     [Yosemite]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Linux SCSI]     [Fedora Users]