[PATCH 4.19 236/280] dm: fix to_sector() for 32bit

From: Greg Kroah-Hartman
Date: Fri Mar 22 2019 - 08:09:12 EST

4.19-stable review patch. If anyone has any objections, please let me know.


From: NeilBrown <neil@xxxxxxxxxx>

commit 0bdb50c531f7377a9da80d3ce2d61f389c84cb30 upstream.

A dm-raid array with devices larger than 4GB won't assemble on
a 32 bit host since _check_data_dev_sectors() was added in 4.16.
This is because to_sector() treats its argument as an "unsigned long"
which is 32bits (4GB) on a 32bit host. Using "unsigned long long"
is more correct.

Kernels as early as 4.2 can have other problems due to to_sector()
being used on the size of a device.

Fixes: 0cf4503174c1 ("dm raid: add support for the MD RAID0 personality")
cc: stable@xxxxxxxxxxxxxxx (v4.2+)
Reported-and-tested-by: Guillaume PerrÃal <gperreal@xxxxxxx>
Signed-off-by: NeilBrown <neil@xxxxxxxxxx>
Signed-off-by: Mike Snitzer <snitzer@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

include/linux/device-mapper.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/include/linux/device-mapper.h
+++ b/include/linux/device-mapper.h
@@ -601,7 +601,7 @@ do { \
#define dm_target_offset(ti, sector) ((sector) - (ti)->begin)

-static inline sector_t to_sector(unsigned long n)
+static inline sector_t to_sector(unsigned long long n)
return (n >> SECTOR_SHIFT);