btrfs: avoid overflow when sector_t is 32 bit
BugLink: http://bugs.launchpad.net/bugs/1723145
commit
2d8ce70a08fe033c904115d59276ad86adeaa337 upstream.
Jean-Denis Girard noticed commit
c821e7f3 "pass bytes to
btrfs_bio_alloc" (https://patchwork.kernel.org/patch/
9763081/)
introduces a regression on 32 bit machines.
When CONFIG_LBDAF is _not_ defined (CONFIG_LBDAF == Support for large
(2TB+) block devices and files) sector_t is 32 bit on 32bit machines.
In the function submit_extent_page, 'sector' (which is sector_t type) is
multiplied by 512 to convert it from sectors to bytes, leading to an
overflow when the disk is bigger than 4GB (!).
I added a cast to u64 to avoid overflow.
Fixes: c821e7f3 ("btrfs: pass bytes to btrfs_bio_alloc")
Signed-off-by: Goffredo Baroncelli <kreijack@inwind.it>
Tested-by: Jean-Denis Girard <jd.girard@sysnux.pf>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>