s390/sclp_ctl: fix potential information leak with /dev/sclp

Browse source

commit 532c34b5fb upstream.

The sclp_ctl_ioctl_sccb function uses two copy_from_user calls to
retrieve the sclp request from user space. The first copy_from_user
fetches the length of the request which is stored in the first two
bytes of the request. The second copy_from_user gets the complete
sclp request, but this copies the length field a second time.
A malicious user may have changed the length in the meantime.

Reported-by: Pengfei Wang <wpengfeinudt@gmail.com>
Reviewed-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

...

This commit is contained in:

Martin Schwidefsky 2016-04-25 17:54:28 +02:00 • committed by Ben Hutchings

parent 81bba9ff4d

commit 8229d94ade

1 changed files with 7 additions and 5 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

12

drivers/s390/char/sclp_ctl.c

View file