From: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
First of all, __put_user() can fail with access_ok() succeeding.
And access_ok() + __copy_to_user() is spelled copy_to_user()...
__put_user() *can* fail with access_ok() succeeding...
Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
---
drivers/scsi/sg.c | 43 ++++++++++++++++---------------------------
1 file changed, 16 insertions(+), 27 deletions(-)
diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c
index cce757506383..634460421ce4 100644
--- a/drivers/scsi/sg.c
+++ b/drivers/scsi/sg.c
@@ -963,26 +963,21 @@ sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
case SG_GET_LOW_DMA:
return put_user((int) sdp->device->host->unchecked_isa_dma, ip);
case SG_GET_SCSI_ID:
- if (!access_ok(p, sizeof (sg_scsi_id_t)))
- return -EFAULT;
- else {
- sg_scsi_id_t __user *sg_idp = p;
+ {
+ sg_scsi_id_t v;
if (atomic_read(&sdp->detaching))
return -ENODEV;
- __put_user((int) sdp->device->host->host_no,
- &sg_idp->host_no);
- __put_user((int) sdp->device->channel,
- &sg_idp->channel);
- __put_user((int) sdp->device->id, &sg_idp->scsi_id);
- __put_user((int) sdp->device->lun, &sg_idp->lun);
- __put_user((int) sdp->device->type, &sg_idp->scsi_type);
- __put_user((short) sdp->device->host->cmd_per_lun,
- &sg_idp->h_cmd_per_lun);
- __put_user((short) sdp->device->queue_depth,
- &sg_idp->d_queue_depth);
- __put_user(0, &sg_idp->unused[0]);
- __put_user(0, &sg_idp->unused[1]);
+ memset(&v, 0, sizeof(v));
+ v.host_no = sdp->device->host->host_no;
+ v.channel = sdp->device->channel;
+ v.scsi_id = sdp->device->id;
+ v.lun = sdp->device->lun;
+ v.scsi_type = sdp->device->type;
+ v.h_cmd_per_lun = sdp->device->host->cmd_per_lun;
+ v.d_queue_depth = sdp->device->queue_depth;
+ if (copy_to_user(p, &v, sizeof(sg_scsi_id_t)))
+ return -EFAULT;
return 0;
}
case SG_SET_FORCE_PACK_ID:
@@ -992,20 +987,16 @@ sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
sfp->force_packid = val ? 1 : 0;
return 0;
case SG_GET_PACK_ID:
- if (!access_ok(ip, sizeof (int)))
- return -EFAULT;
read_lock_irqsave(&sfp->rq_list_lock, iflags);
list_for_each_entry(srp, &sfp->rq_list, entry) {
if ((1 == srp->done) && (!srp->sg_io_owned)) {
read_unlock_irqrestore(&sfp->rq_list_lock,
iflags);
- __put_user(srp->header.pack_id, ip);
- return 0;
+ return put_user(srp->header.pack_id, ip);
}
}
read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
- __put_user(-1, ip);
- return 0;
+ return put_user(-1, ip);
case SG_GET_NUM_WAITING:
read_lock_irqsave(&sfp->rq_list_lock, iflags);
val = 0;
@@ -1073,9 +1064,7 @@ sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
val = (sdp->device ? 1 : 0);
return put_user(val, ip);
case SG_GET_REQUEST_TABLE:
- if (!access_ok(p, SZ_SG_REQ_INFO * SG_MAX_QUEUE))
- return -EFAULT;
- else {
+ {
sg_req_info_t *rinfo;
rinfo = kcalloc(SG_MAX_QUEUE, SZ_SG_REQ_INFO,
@@ -1085,7 +1074,7 @@ sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
read_lock_irqsave(&sfp->rq_list_lock, iflags);
sg_fill_request_table(sfp, rinfo);
read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
- result = __copy_to_user(p, rinfo,
+ result = copy_to_user(p, rinfo,
SZ_SG_REQ_INFO * SG_MAX_QUEUE);
result = result ? -EFAULT : 0;
kfree(rinfo);
--
2.11.0
