IB/uverbs: Fix possible oops with duplicate ioctl attributes
commit4d39a959bc1f3d164b5a54147fdeb19f84b1ed58
authorMatan Barak <matanb@mellanox.com>
Tue, 13 Feb 2018 10:18:35 +0000 (13 12:18 +0200)
committerJason Gunthorpe <jgg@mellanox.com>
Thu, 15 Feb 2018 21:59:46 +0000 (15 14:59 -0700)
tree394a96ddf6867a6435398f840d310802fc4a0bbb
parent9dfb2ff400f6c0a52f63014b5331b64ee7bd5c19
IB/uverbs: Fix possible oops with duplicate ioctl attributes

If the same attribute is listed twice by the user in the ioctl attribute
list then error unwind can cause the kernel to deref garbage.

This happens when an object with WRITE access is sent twice. The second
parse properly fails but corrupts the state required for the error unwind
it triggers.

Fixing this by making duplicates in the attribute list invalid. This is
not something we need to support.

The ioctl interface is currently recommended to be disabled in kConfig.

Signed-off-by: Matan Barak <matanb@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
drivers/infiniband/core/uverbs_ioctl.c