From 505fa2c4a2f125a70951926dfb22b9cf273994f1 Mon Sep 17 00:00:00 2001 From: Neil Brown <neilb@suse.de> Date: Wed, 11 Apr 2007 23:28:44 -0700 Subject: [PATCH] md: fix calculation for size of filemap_attr array in md/bitmap If 'num_pages' were ever 1 more than a multiple of 8 (32bit platforms) or of 16 (64 bit platforms). filemap_attr would be allocated one 'unsigned long' shorter than required. We need a round-up in there. Signed-off-by: Neil Brown <neilb@suse.de> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> --- drivers/md/bitmap.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) (limited to 'drivers/md') diff --git a/drivers/md/bitmap.c b/drivers/md/bitmap.c index 5554adaa58f9..e61e0efe9ec7 100644 --- a/drivers/md/bitmap.c +++ b/drivers/md/bitmap.c @@ -863,9 +863,7 @@ static int bitmap_init_from_disk(struct bitmap *bitmap, sector_t start) /* We need 4 bits per page, rounded up to a multiple of sizeof(unsigned long) */ bitmap->filemap_attr = kzalloc( - (((num_pages*4/8)+sizeof(unsigned long)-1) - /sizeof(unsigned long)) - *sizeof(unsigned long), + roundup( DIV_ROUND_UP(num_pages*4, 8), sizeof(unsigned long)), GFP_KERNEL); if (!bitmap->filemap_attr) goto out; -- cgit v1.2.3