6.11-stable review patch. If anyone has any objections, please let me know.
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From: John Garry john.g.garry@oracle.com
[ Upstream commit d28d17a845600dd9f7de241de9b1528a1b138716 ]
If the sg_copy_buffer() call returns less than sdebug_sector_size, then we drop out of the copy loop. However, we still report that we copied the full expected amount, which is not proper.
Fix by keeping a running total and return that value.
Fixes: 84f3a3c01d70 ("scsi: scsi_debug: Atomic write support") Reported-by: Colin Ian King colin.i.king@gmail.com Suggested-by: Dan Carpenter dan.carpenter@linaro.org Signed-off-by: John Garry john.g.garry@oracle.com Link: https://lore.kernel.org/r/20241018101655.4207-1-john.g.garry@oracle.com Reviewed-by: Dan Carpenter dan.carpenter@linaro.org Reviewed-by: Colin Ian King colin.i.king@gmail.com Signed-off-by: Martin K. Petersen martin.petersen@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/scsi/scsi_debug.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-)
diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c index a9d8a9c62663e..e41698218e62f 100644 --- a/drivers/scsi/scsi_debug.c +++ b/drivers/scsi/scsi_debug.c @@ -3652,7 +3652,7 @@ static int do_device_access(struct sdeb_store_info *sip, struct scsi_cmnd *scp, enum dma_data_direction dir; struct scsi_data_buffer *sdb = &scp->sdb; u8 *fsp; - int i; + int i, total = 0;
/* * Even though reads are inherently atomic (in this driver), we expect @@ -3689,18 +3689,16 @@ static int do_device_access(struct sdeb_store_info *sip, struct scsi_cmnd *scp, fsp + (block * sdebug_sector_size), sdebug_sector_size, sg_skip, do_write); sdeb_data_sector_unlock(sip, do_write); - if (ret != sdebug_sector_size) { - ret += (i * sdebug_sector_size); + total += ret; + if (ret != sdebug_sector_size) break; - } sg_skip += sdebug_sector_size; if (++block >= sdebug_store_sectors) block = 0; } - ret = num * sdebug_sector_size; sdeb_data_unlock(sip, atomic);
- return ret; + return total; }
/* Returns number of bytes copied or -1 if error. */