scsi: stex: Properly zero out the passthrough command structure

commit 6022f210461fef67e6e676fd8544ca02d1bcfa7a upstream.

The passthrough structure is declared off of the stack, so it needs to be
set to zero before copied back to userspace to prevent any unintentional
data leakage.  Switch things to be statically allocated which will fill the
unused fields with 0 automatically.

Link: https://lore.kernel.org/r/YxrjN3OOw2HHl9tx@kroah.com
Cc: stable@kernel.org
Cc: "James E.J. Bottomley" <jejb@linux.ibm.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Reported-by: hdthky <hdthky0@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/scsi/stex.c b/drivers/scsi/stex.c
index 9b20643ab49de59fee1ee2d90e9a433d3fb1a4f7..124a5d0ec05cad5bb5c907a01315837e6d7d6f95 100644 (file)
--- a/drivers/scsi/stex.c
+++ b/drivers/scsi/stex.c
@@ -673,16 +673,17 @@ stex_queuecommand_lck(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *))
                return 0;
        case PASSTHRU_CMD:
                if (cmd->cmnd[1] == PASSTHRU_GET_DRVVER) {
-                       struct st_drvver ver;
+                       const struct st_drvver ver = {
+                               .major = ST_VER_MAJOR,
+                               .minor = ST_VER_MINOR,
+                               .oem = ST_OEM,
+                               .build = ST_BUILD_VER,
+                               .signature[0] = PASSTHRU_SIGNATURE,
+                               .console_id = host->max_id - 1,
+                               .host_no = hba->host->host_no,
+                       };
                        size_t cp_len = sizeof(ver);
 
-                       ver.major = ST_VER_MAJOR;
-                       ver.minor = ST_VER_MINOR;
-                       ver.oem = ST_OEM;
-                       ver.build = ST_BUILD_VER;
-                       ver.signature[0] = PASSTHRU_SIGNATURE;
-                       ver.console_id = host->max_id - 1;
-                       ver.host_no = hba->host->host_no;
                        cp_len = scsi_sg_copy_from_buffer(cmd, &ver, cp_len);
                        cmd->result = sizeof(ver) == cp_len ?
                                DID_OK << 16 | COMMAND_COMPLETE << 8 :

diff --git a/include/scsi/scsi_cmnd.h b/include/scsi/scsi_cmnd.h
index 7bc752fc98de777d65b3c69a78d84944703e4c26..618a4bff500f78d79decd9c6ccaf40f541491203 100644 (file)
--- a/include/scsi/scsi_cmnd.h
+++ b/include/scsi/scsi_cmnd.h
@@ -225,7 +225,7 @@ static inline struct scsi_data_buffer *scsi_out(struct scsi_cmnd *cmd)
 }
 
 static inline int scsi_sg_copy_from_buffer(struct scsi_cmnd *cmd,
-                                          void *buf, int buflen)
+                                          const void *buf, int buflen)
 {
        return sg_copy_from_buffer(scsi_sglist(cmd), scsi_sg_count(cmd),
                                   buf, buflen);