diff options
| author | Al Viro <viro@zeniv.linux.org.uk> | 2016-12-16 13:42:06 -0500 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-01-09 08:32:25 +0100 |
| commit | 3f3a6bbe6f9f5e895d8945494173594ee51632da (patch) | |
| tree | 07d69582b4b05fe1b7cf99dc58ab907eb4d0113a /drivers/scsi | |
| parent | d024532a97db32db4b0fc4cd27c7a9ac15b84e5b (diff) | |
sg_write()/bsg_write() is not fit to be called under KERNEL_DS
commit 128394eff343fc6d2f32172f03e24829539c5835 upstream.
Both damn things interpret userland pointers embedded into the payload;
worse, they are actually traversing those. Leaving aside the bad
API design, this is very much _not_ safe to call with KERNEL_DS.
Bail out early if that happens.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/scsi')
| -rw-r--r-- | drivers/scsi/sg.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c index 070332eb41f3..dbe5b4b95df0 100644 --- a/drivers/scsi/sg.c +++ b/drivers/scsi/sg.c @@ -581,6 +581,9 @@ sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos) sg_io_hdr_t *hp; unsigned char cmnd[SG_MAX_CDB_SIZE]; + if (unlikely(segment_eq(get_fs(), KERNEL_DS))) + return -EINVAL; + if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))) return -ENXIO; SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, |