scsi: sd_zbc: Fix sd_zbc_check_zones() error checks

The unsigned 32 bits overflow check for the zone size value is already
done within sd_zbc_check_zones() with the test:

} else if (logical_to_sectors(sdkp->device, zone_blocks) > UINT_MAX) {

so there is no need to check again for an out of range value in
sd_zbc_read_zones(). Simplify the code and fix sd_zbc_check_zones()
error return to -EFBIG instead of -ENODEV if the zone size is too large.
Change the return type of sd_zbc_check_zones() to an int for the error
code and return the zone size (zone_blocks) through a u32 pointer to
avoid overflowing the signed 32 return value.

Reviewed-by: Hannes Reinecke <hare@suse.com>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/drivers/scsi/sd_zbc.c b/drivers/scsi/sd_zbc.c
index ca73c46..0678e1e 100644 (file)
--- a/drivers/scsi/sd_zbc.c
+++ b/drivers/scsi/sd_zbc.c
@@ -373,7 +373,7 @@ static int sd_zbc_check_zoned_characteristics(struct scsi_disk *sdkp,
  * Returns the zone size in number of blocks upon success or an error code
  * upon failure.
  */
-static s64 sd_zbc_check_zones(struct scsi_disk *sdkp)
+static int sd_zbc_check_zones(struct scsi_disk *sdkp, u32 *zblocks)
 {
        u64 zone_blocks = 0;
        sector_t max_lba, block = 0;
@@ -381,7 +381,7 @@ static s64 sd_zbc_check_zones(struct scsi_disk *sdkp)
        unsigned char *rec;
        unsigned int buf_len;
        unsigned int list_length;
-       s64 ret;
+       int ret;
        u8 same;
 
        /* Get a buffer */
@@ -472,9 +472,10 @@ out:
                if (sdkp->first_scan)
                        sd_printk(KERN_NOTICE, sdkp,
                                  "Zone size too large\n");
-               ret = -ENODEV;
+               ret = -EFBIG;
        } else {
-               ret = zone_blocks;
+               *zblocks = zone_blocks;
+               ret = 0;
        }
 
 out_free:
@@ -668,7 +669,7 @@ err:
 
 int sd_zbc_read_zones(struct scsi_disk *sdkp, unsigned char *buf)
 {
-       int64_t zone_blocks;
+       u32 zone_blocks;
        int ret;
 
        if (!sd_is_zoned(sdkp))
@@ -687,12 +688,8 @@ int sd_zbc_read_zones(struct scsi_disk *sdkp, unsigned char *buf)
         * Check zone size: only devices with a constant zone size (except
         * an eventual last runt zone) that is a power of 2 are supported.
         */
-       zone_blocks = sd_zbc_check_zones(sdkp);
-       ret = -EFBIG;
-       if (zone_blocks != (u32)zone_blocks)
-               goto err;
-       ret = zone_blocks;
-       if (ret < 0)
+       ret = sd_zbc_check_zones(sdkp, &zone_blocks);
+       if (ret != 0)
                goto err;
 
        /* The drive satisfies the kernel restrictions: set it up */