[PATCH] libata: Avoid overflow in ata_tf_read_block() when tf->hba_lbal > 127

[Roland Dreier <rdreier@cisco.com>]

Phillip O'Donnell <phillip.odonnell@gmail.com> pointed out that the same
sign extension bug that was fixed in commit ba14a9c2 ("libata: Avoid
overflow in ata_tf_to_lba48() when tf->hba_lbal > 127") also appears to
exist in ata_tf_read_block().  Fix this by adding a cast to u64.

Signed-off-by: Roland Dreier <rolandd@cisco.com>
---
I don't have any way to test this -- I guess you would have to get an
error on a block above 2G (ie data above 1TB)?  But it looks "obviously
correct" enough to add to -next I guess.

 drivers/ata/libata-core.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 622350d..a6ad862 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -612,7 +612,7 @@ u64 ata_tf_read_block(struct ata_taskfile *tf, struct ata_device *dev)
 		if (tf->flags & ATA_TFLAG_LBA48) {
 			block |= (u64)tf->hob_lbah << 40;
 			block |= (u64)tf->hob_lbam << 32;
-			block |= tf->hob_lbal << 24;
+			block |= (u64)tf->hob_lbal << 24;
 		} else
 			block |= (tf->device & 0xf) << 24;