From: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
Just use plain copy_from_user() and get_user(). Note that while
a buf-derived pointer gets stored into ->dxferp, all places that
actually use the resulting value feed it either to import_iovec()
or to import_single_range(), and both will do validation.
Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
---
drivers/scsi/sg.c | 8 +++-----
1 file changed, 3 insertions(+), 5 deletions(-)
diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c
index 9f6534a025cd..f3d090b93cdf 100644
--- a/drivers/scsi/sg.c
+++ b/drivers/scsi/sg.c
@@ -612,11 +612,9 @@ sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
scsi_block_when_processing_errors(sdp->device)))
return -ENXIO;
- 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;
blocking = !(filp->f_flags & O_NONBLOCK);
if (old_hdr.reply_len < 0)
@@ -626,7 +624,7 @@ sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
return -EIO; /* The minimum scsi command length is 6 bytes. */
buf += SZ_SG_HEADER;
- if (__get_user(opcode, buf))
+ if (get_user(opcode, buf))
return -EFAULT;
if (!(srp = sg_add_request(sfp))) {
@@ -676,7 +674,7 @@ 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,
--
2.11.0
