linux/drivers/infiniband
Yann Droneaud 9d194d1025 IB/nes: Return an error on ib_copy_from_udata() failure instead of NULL
In case of error while accessing to userspace memory, function
nes_create_qp() returns NULL instead of an error code wrapped through
ERR_PTR().  But NULL is not expected by ib_uverbs_create_qp(), as it
check for error with IS_ERR().

As page 0 is likely not mapped, it is going to trigger an Oops when
the kernel will try to dereference NULL pointer to access to struct
ib_qp's fields.

In some rare cases, page 0 could be mapped by userspace, which could
turn this bug to a vulnerability that could be exploited: the function
pointers in struct ib_device will be under userspace total control.

This was caught when using spatch (aka. coccinelle)
to rewrite calls to ib_copy_{from,to}_udata().

Link: https://www.gitorious.org/opteya/ib-hw-nes-create-qp-null
Link: 75ebf2c103:ib_copy_udata.cocci
Link: http://marc.info/?i=cover.1394485254.git.ydroneaud@opteya.com
Cc: <stable@vger.kernel.org>
Signed-off-by: Yann Droneaud <ydroneaud@opteya.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
2014-03-17 16:20:28 -07:00
..
core Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2014-01-25 11:17:34 -08:00
hw IB/nes: Return an error on ib_copy_from_udata() failure instead of NULL 2014-03-17 16:20:28 -07:00
ulp Merge git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending 2014-02-15 16:18:47 -08:00
Kconfig Merge branch 'ip-roce' into for-next 2014-01-22 23:24:21 -08:00
Makefile IB/usnic: Add Cisco VIC low-level hardware driver 2014-01-14 00:44:28 -08:00