diff options
| author | Al Viro <viro@zeniv.linux.org.uk> | 2019-10-17 20:39:22 +0100 |
|---|---|---|
| committer | Martin K. Petersen <martin.petersen@oracle.com> | 2019-11-06 00:04:03 -0500 |
| commit | d9fc5617bcb6f8278ffedd0f25bfbb697da5ca87 (patch) | |
| tree | 675b821667fa27f235ef8e95cd2487baa0b83b3f | |
| parent | c35a5cfb41509c2214228aa321509ffd91cbf063 (diff) | |
scsi: sg: sg_new_write(): don't bother with access_ok
... just use copy_from_user(). We copy only SZ_SG_IO_HDR bytes, so that
would, strictly speaking, loosen the check. However, for call chains via
->write() the caller has actually checked the entire range and SG_IO passes
exactly SZ_SG_IO_HDR for count. So no visible behaviour changes happen if
we check only what we really need for copyin.
Link: https://lore.kernel.org/r/20191017193925.25539-5-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>
| -rw-r--r-- | drivers/scsi/sg.c | 4 |
1 files changed, 1 insertions, 3 deletions
diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c index 2d30e89075e9..3702f66493f7 100644 --- a/drivers/scsi/sg.c +++ b/drivers/scsi/sg.c @@ -717,8 +717,6 @@ sg_new_write(Sg_fd *sfp, struct file *file, 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))) { @@ -728,7 +726,7 @@ sg_new_write(Sg_fd *sfp, struct file *file, 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; } |