4.14-stable review patch. If anyone has any objections, please let me know.
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From: Matan Barak matanb@mellanox.com
[ Upstream commit 4d39a959bc1f3d164b5a54147fdeb19f84b1ed58 ]
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 Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/infiniband/core/uverbs_ioctl.c | 3 +++ 1 file changed, 3 insertions(+)
--- a/drivers/infiniband/core/uverbs_ioctl.c +++ b/drivers/infiniband/core/uverbs_ioctl.c @@ -59,6 +59,9 @@ static int uverbs_process_attr(struct ib return 0; }
+ if (test_bit(attr_id, attr_bundle_h->valid_bitmap)) + return -EINVAL; + spec = &attr_spec_bucket->attrs[attr_id]; e = &elements[attr_id]; e->uattr = uattr_ptr;