Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1375093

[PATCH 3.14 10/76] sg: fix dxferp in from_to case

Show all headers | View raw

3.14-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Douglas Gilbert <dgilbert@interlog.com>

commit 5ecee0a3ee8d74b6950cb41e8989b0c2174568d4 upstream.

One of the strange things that the original sg driver did was let the
user provide both a data-out buffer (it followed the sg_header+cdb)
_and_ specify a reply length greater than zero. What happened was that
the user data-out buffer was copied into some kernel buffers and then
the mid level was told a read type operation would take place with the
data from the device overwriting the same kernel buffers. The user would
then read those kernel buffers back into the user space.

>From what I can tell, the above action was broken by commit fad7f01e61bf
("sg: set dxferp to NULL for READ with the older SG interface") in 2008
and syzkaller found that out recently.

Make sure that a user space pointer is passed through when data follows
the sg_header structure and command.  Fix the abnormal case when a
non-zero reply_len is also given.

Fixes: fad7f01e61bf737fe8a3740d803f000db57ecac6
Signed-off-by: Douglas Gilbert <dgilbert@interlog.com>
Reviewed-by: Ewan Milne <emilne@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/scsi/sg.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/drivers/scsi/sg.c
+++ b/drivers/scsi/sg.c
@@ -633,7 +633,8 @@ sg_write(struct file *filp, const char _
 	else
 		hp->dxfer_direction = (mxsize > 0) ? SG_DXFER_FROM_DEV : SG_DXFER_NONE;
 	hp->dxfer_len = mxsize;
-	if (hp->dxfer_direction == SG_DXFER_TO_DEV)
+	if ((hp->dxfer_direction == SG_DXFER_TO_DEV) ||
+	    (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV))
 		hp->dxferp = (char __user *)buf + cmd_size;
 	else
 		hp->dxferp = NULL;

Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

[PATCH 3.14 00/76] 3.14.66-stable review Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-04-10 21:40 +0200
  [PATCH 3.14 07/76] PCI: Disable IO/MEM decoding for devices with non-compliant BARs Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-04-10 21:40 +0200
  [PATCH 3.14 41/76] [media] saa7134: Fix bytesperline not being set correctly for planar formats Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-04-10 21:40 +0200
  [PATCH 3.14 40/76] 8250: use callbacks to access UART_DLL/UART_DLM Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-04-10 21:40 +0200
  [PATCH 3.14 26/76] Input: powermate - fix oops with malicious USB descriptors Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-04-10 21:40 +0200
  [PATCH 3.14 45/76] ALSA: intel8x0: Add clock quirk entry for AD1981B on IBM ThinkPad X41. Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-04-10 21:40 +0200
  [PATCH 3.14 25/76] [media] pwc: Add USB id for Philips Spc880nc webcam Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-04-10 21:40 +0200
  [PATCH 3.14 11/76] aacraid: Fix memory leak in aac_fib_map_free Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-04-10 21:50 +0200
  [PATCH 3.14 10/76] sg: fix dxferp in from_to case Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-04-10 21:50 +0200
  [PATCH 3.14 13/76] usb: retry reset if a device times out Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-04-10 21:50 +0200
  Re: [PATCH 3.14 00/76] 3.14.66-stable review Guenter Roeck <linux@roeck-us.net> - 2016-04-10 22:10 +0200
    Re: [PATCH 3.14 00/76] 3.14.66-stable review Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-04-10 22:40 +0200
  [PATCH 3.14 68/76] target: Fix target_release_cmd_kref shutdown comp leak Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-04-10 22:40 +0200
  [PATCH 3.14 64/76] tracing: Fix trace_printk() to print when not using bprintk() Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-04-10 22:40 +0200
  Re: [PATCH 3.14 00/76] 3.14.66-stable review Guenter Roeck <linux@roeck-us.net> - 2016-04-11 05:20 +0200
    Re: [PATCH 3.14 00/76] 3.14.66-stable review Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-04-12 16:20 +0200
  Re: [PATCH 3.14 00/76] 3.14.66-stable review shuahkh <shuahkh@osg.sisa.samsung.com> - 2016-04-11 19:30 +0200

csiph-web