The patch titled
scsi: fix sign extension with 1.5TB usb-storage LBD=y
has been added to the -mm tree. Its filename is
scsi-fix-sign-extension-with-15tb-usb-storage-lbd=y.patch
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------------------------------------------------------
Subject: scsi: fix sign extension with 1.5TB usb-storage LBD=y
From: Dave Hansen <dave@xxxxxxxxxxxxxxxxxx>
Shifting an unsigned char implicitly casts it to a signed int. This
caused 'lba' to sign-extend and Linux would then try READ CAPACITY 16
which was not supported by at least one drive. Using the
get_unaligned_be*() helpers keeps us from having to worry about how the
extension might occur.
Signed-off-by: Dave Hansen <dave@xxxxxxxxxxxxxxxxxx>
Reviewed-by: Matthew Wilcox <willy@xxxxxxxxxxxxxxx>
Cc: James Bottomley <James.Bottomley@xxxxxxxxxxxxxxxxxxxxx>
Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
drivers/scsi/sd.c | 15 +++++----------
1 file changed, 5 insertions(+), 10 deletions(-)
diff -puN drivers/scsi/sd.c~scsi-fix-sign-extension-with-15tb-usb-storage-lbd=y drivers/scsi/sd.c
--- a/drivers/scsi/sd.c~scsi-fix-sign-extension-with-15tb-usb-storage-lbd=y
+++ a/drivers/scsi/sd.c
@@ -50,6 +50,7 @@
#include <linux/string_helpers.h>
#include <linux/async.h>
#include <asm/uaccess.h>
+#include <asm/unaligned.h>
#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
@@ -1345,12 +1346,8 @@ static int read_capacity_16(struct scsi_
return -EINVAL;
}
- sector_size = (buffer[8] << 24) | (buffer[9] << 16) |
- (buffer[10] << 8) | buffer[11];
- lba = (((u64)buffer[0] << 56) | ((u64)buffer[1] << 48) |
- ((u64)buffer[2] << 40) | ((u64)buffer[3] << 32) |
- ((u64)buffer[4] << 24) | ((u64)buffer[5] << 16) |
- ((u64)buffer[6] << 8) | (u64)buffer[7]);
+ sector_size = get_unaligned_be32(&buffer[8]);
+ lba = get_unaligned_be64(&buffer[0]);
sd_read_protection_type(sdkp, buffer);
@@ -1401,10 +1398,8 @@ static int read_capacity_10(struct scsi_
return -EINVAL;
}
- sector_size = (buffer[4] << 24) | (buffer[5] << 16) |
- (buffer[6] << 8) | buffer[7];
- lba = (buffer[0] << 24) | (buffer[1] << 16) |
- (buffer[2] << 8) | buffer[3];
+ sector_size = get_unaligned_be32(&buffer[4]);
+ lba = get_unaligned_be32(&buffer[0]);
if ((sizeof(sdkp->capacity) == 4) && (lba == 0xffffffff)) {
sd_printk(KERN_ERR, sdkp, "Too big for this kernel. Use a "
_
Patches currently in -mm which might be from dave@xxxxxxxxxxxxxxxxxx are
linux-next.patch
scsi-fix-sign-extension-with-15tb-usb-storage-lbd=y.patch
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