diff options
| author |   Al Viro <viro@zeniv.linux.org.uk> | 2019-10-17 20:39:21 +0100 |
|---|---|---|
| committer |   Martin K. Petersen <martin.petersen@oracle.com> | 2019-11-06 00:04:03 -0500 |
| commit | c35a5cfb41509c2214228aa321509ffd91cbf063 (patch) | |
| tree | d048d4a53a89eb168c390cf9e1d79b12ddd9312d /drivers/scsi/sg.c | |
| parent | scsi: sg: sg_write(): __get_user() can fail... (diff) | |
| download | linux-dev-c35a5cfb41509c2214228aa321509ffd91cbf063.tar.xz linux-dev-c35a5cfb41509c2214228aa321509ffd91cbf063.zip | |
scsi: sg: sg_read(): simplify reading ->pack_id of userland sg_io_hdr_t
We don't need to allocate a temporary buffer and read the entire structure
in it, only to fetch a single field and free what we'd allocated. Just use
get_user() and be done with it...
Link: https://lore.kernel.org/r/20191017193925.25539-4-viro@ZenIV.linux.org.uk
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Douglas Gilbert <dgilbert@interlog.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Diffstat (limited to '')
| -rw-r--r-- | drivers/scsi/sg.c | 13 |
1 files changed, 2 insertions, 11 deletions
diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c index 4c62237cdf37..2d30e89075e9 100644 --- a/drivers/scsi/sg.c +++ b/drivers/scsi/sg.c @@ -441,17 +441,8 @@ sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos) } if (old_hdr->reply_len < 0) { if (count >= SZ_SG_IO_HDR) { - sg_io_hdr_t *new_hdr; - new_hdr = kmalloc(SZ_SG_IO_HDR, GFP_KERNEL); - if (!new_hdr) { - retval = -ENOMEM; - goto free_old_hdr; - } - retval =__copy_from_user - (new_hdr, buf, SZ_SG_IO_HDR); - req_pack_id = new_hdr->pack_id; - kfree(new_hdr); - if (retval) { + sg_io_hdr_t __user *p = (void __user *)buf; + if (get_user(req_pack_id, &p->pack_id)) { retval = -EFAULT; goto free_old_hdr; } |