diff options
author | Al Viro <viro@zeniv.linux.org.uk> | 2016-12-16 13:42:06 -0500 |
---|---|---|
committer | Sasha Levin <alexander.levin@verizon.com> | 2017-01-12 20:56:58 -0500 |
commit | 3e3267311e3b6557206f293eeb9205b41e090625 (patch) | |
tree | 1c98d91c0c9bd7f67b5cb738fdebafd3a29f6c08 /drivers | |
parent | 363f1a90b7f3057efa6e08bf7b707874232f153c (diff) |
sg_write()/bsg_write() is not fit to be called under KERNEL_DS
[ Upstream commit 128394eff343fc6d2f32172f03e24829539c5835 ]
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>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Diffstat (limited to 'drivers')
-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 ec192939750e..26bc4e9c7441 100644 --- a/drivers/scsi/sg.c +++ b/drivers/scsi/sg.c @@ -592,6 +592,9 @@ 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, |