Since access_ok() has lost it direction (3rd) parameter there
seems to be no benefit in calling access_ok() before
__copy_{to|from}_user(). Simplify code by using the variant of
these functions that do not start with "__".

Signed-off-by: Douglas Gilbert <dgilb...@interlog.com>
---
 drivers/scsi/sg.c | 50 ++++++++++++++++-------------------------------
 1 file changed, 17 insertions(+), 33 deletions(-)

diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c
index 7e188ac2f182..123d8516a9a0 100644
--- a/drivers/scsi/sg.c
+++ b/drivers/scsi/sg.c
@@ -502,11 +502,9 @@ sg_write(struct file *filp, const char __user *buf, size_t 
count, loff_t * ppos)
        if (res)
                return res;
 
-       if (!access_ok(buf, count))
-               return -EFAULT; /* protects following copy_from_user()s + 
get_user()s */
        if (count < SZ_SG_HEADER)
                return -EIO;
-       if (__copy_from_user(&old_hdr, buf, SZ_SG_HEADER))
+       if (copy_from_user(&old_hdr, buf, SZ_SG_HEADER))
                return -EFAULT;
        if (old_hdr.reply_len < 0)
                return sg_submit(sfp, filp, buf, count, blocking, false, false,
@@ -561,7 +559,7 @@ sg_write(struct file *filp, const char __user *buf, size_t 
count, loff_t * ppos)
        hp->flags = input_size; /* structure abuse ... */
        hp->pack_id = old_hdr.pack_id;
        hp->usr_ptr = NULL;
-       if (__copy_from_user(cmnd, buf, cmd_size))
+       if (copy_from_user(cmnd, buf, cmd_size))
                return -EFAULT;
        /*
         * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV,
@@ -607,8 +605,6 @@ sg_submit(struct sg_fd *sfp, struct file *filp, const char 
__user *buf,
 
        if (count < SZ_SG_IO_HDR)
                return -EINVAL;
-       if (!access_ok(buf, count))
-               return -EFAULT; /* protects following copy_from_user()s + 
get_user()s */
 
        sfp->cmd_q = 1; /* when sg_io_hdr seen, set command queuing on */
        if (!(srp = sg_add_request(sfp))) {
@@ -617,7 +613,7 @@ sg_submit(struct sg_fd *sfp, struct file *filp, const char 
__user *buf,
        }
        srp->sg_io_owned = sg_io_owned;
        hp = &srp->header;
-       if (__copy_from_user(hp, buf, SZ_SG_IO_HDR)) {
+       if (copy_from_user(hp, buf, SZ_SG_IO_HDR)) {
                sg_remove_request(sfp, srp);
                return -EFAULT;
        }
@@ -645,11 +641,7 @@ sg_submit(struct sg_fd *sfp, struct file *filp, const char 
__user *buf,
                sg_remove_request(sfp, srp);
                return -EMSGSIZE;
        }
-       if (!access_ok(hp->cmdp, hp->cmd_len)) {
-               sg_remove_request(sfp, srp);
-               return -EFAULT; /* protects following copy_from_user()s + 
get_user()s */
-       }
-       if (__copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) {
+       if (copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) {
                sg_remove_request(sfp, srp);
                return -EFAULT;
        }
@@ -829,13 +821,11 @@ sg_read(struct file *filp, char __user *buf, size_t 
count, loff_t *ppos)
        if (ret)
                return ret;
 
-       if (!access_ok(buf, count))
-               return -EFAULT;
        if (sfp->force_packid && (count >= SZ_SG_HEADER)) {
                old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
                if (!old_hdr)
                        return -ENOMEM;
-               if (__copy_from_user(old_hdr, buf, SZ_SG_HEADER)) {
+               if (copy_from_user(old_hdr, buf, SZ_SG_HEADER)) {
                        ret = -EFAULT;
                        goto free_old_hdr;
                }
@@ -848,8 +838,8 @@ sg_read(struct file *filp, char __user *buf, size_t count, 
loff_t *ppos)
                                        ret = -ENOMEM;
                                        goto free_old_hdr;
                                }
-                               ret = __copy_from_user
-                                   (new_hdr, buf, SZ_SG_IO_HDR);
+                               ret = copy_from_user(new_hdr, buf,
+                                                    SZ_SG_IO_HDR);
                                req_pack_id = new_hdr->pack_id;
                                kfree(new_hdr);
                                if (ret) {
@@ -942,7 +932,7 @@ sg_read(struct file *filp, char __user *buf, size_t count, 
loff_t *ppos)
 
        /* Now copy the result back to the user buffer.  */
        if (count >= SZ_SG_HEADER) {
-               if (__copy_to_user(buf, old_hdr, SZ_SG_HEADER)) {
+               if (copy_to_user(buf, old_hdr, SZ_SG_HEADER)) {
                        ret = -EFAULT;
                        goto free_old_hdr;
                }
@@ -1032,8 +1022,6 @@ sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned 
long arg)
                result = sg_allow_if_err_recovery(sdp, false);
                if (result)
                        return result;
-               if (!access_ok(p, SZ_SG_IO_HDR))
-                       return -EFAULT;
                result = sg_submit(sfp, filp, p, SZ_SG_IO_HDR, true, read_only,
                                   true, &srp);
                if (result < 0)
@@ -1107,19 +1095,17 @@ 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);
+                               put_user(srp->header.pack_id, ip);
                                return 0;
                        }
                }
                read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
-               __put_user(-1, ip);
+               put_user(-1, ip);
                return 0;
        case SG_GET_NUM_WAITING:
                return put_user(atomic_read(&sfp->waiting), ip);
@@ -1181,9 +1167,7 @@ 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,
@@ -1193,8 +1177,8 @@ 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,
-                                               SZ_SG_REQ_INFO * SG_MAX_QUEUE);
+                       result = copy_to_user(p, rinfo,
+                                             SZ_SG_REQ_INFO * SG_MAX_QUEUE);
                        result = result ? -EFAULT : 0;
                        kfree(rinfo);
                        return result;
@@ -2083,13 +2067,13 @@ sg_rd_append(struct sg_request *srp, void __user *outp, 
int num_xfer)
        num = 1 << (PAGE_SHIFT + schp->page_order);
        for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
                if (num > num_xfer) {
-                       if (__copy_to_user(outp, page_address(schp->pages[k]),
-                                          num_xfer))
+                       if (copy_to_user(outp, page_address(schp->pages[k]),
+                                        num_xfer))
                                return -EFAULT;
                        break;
                } else {
-                       if (__copy_to_user(outp, page_address(schp->pages[k]),
-                                          num))
+                       if (copy_to_user(outp, page_address(schp->pages[k]),
+                                        num))
                                return -EFAULT;
                        num_xfer -= num;
                        if (num_xfer <= 0)
-- 
2.22.0

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