diff options
author | Al Viro <viro@zeniv.linux.org.uk> | 2016-12-16 19:42:06 +0100 |
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committer | Al Viro <viro@zeniv.linux.org.uk> | 2016-12-23 05:03:42 +0100 |
commit | 128394eff343fc6d2f32172f03e24829539c5835 (patch) | |
tree | 025d426075681b9904895045929e322429b8a251 /drivers/scsi/sg.c | |
parent | ufs: fix function declaration for ufs_truncate_blocks (diff) | |
download | linux-128394eff343fc6d2f32172f03e24829539c5835.tar.xz linux-128394eff343fc6d2f32172f03e24829539c5835.zip |
sg_write()/bsg_write() is not fit to be called under KERNEL_DS
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.
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to '')
-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, |