From 84b00cd90f4dcd95e64ae6eb7d528deffa0a69cd Mon Sep 17 00:00:00 2001 From: Boris Pismenny Date: Tue, 27 Jun 2017 15:09:13 +0300 Subject: [PATCH] RDMA/uverbs: Check port number supplied by user verbs cmds commit 5ecce4c9b17bed4dc9cb58bfb10447307569b77b upstream. The ib_uverbs_create_ah() ind ib_uverbs_modify_qp() calls receive the port number from user input as part of its attributes and assumes it is valid. Down on the stack, that parameter is used to access kernel data structures. If the value is invalid, the kernel accesses memory it should not. To prevent this, verify the port number before using it. BUG: KASAN: use-after-free in ib_uverbs_create_ah+0x6d5/0x7b0 Read of size 4 at addr ffff880018d67ab8 by task syz-executor/313 BUG: KASAN: slab-out-of-bounds in modify_qp.isra.4+0x19d0/0x1ef0 Read of size 4 at addr ffff88006c40ec58 by task syz-executor/819 Fixes: 67cdb40ca444 ("[IB] uverbs: Implement more commands") Cc: Yevgeny Kliteynik Cc: Tziporet Koren Cc: Alex Polak Signed-off-by: Boris Pismenny Signed-off-by: Leon Romanovsky Signed-off-by: Doug Ledford Signed-off-by: Greg Kroah-Hartman --- drivers/infiniband/core/uverbs_cmd.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/infiniband/core/uverbs_cmd.c b/drivers/infiniband/core/uverbs_cmd.c index cb3f515a2285..01e3a37b0aef 100644 --- a/drivers/infiniband/core/uverbs_cmd.c +++ b/drivers/infiniband/core/uverbs_cmd.c @@ -2342,6 +2342,10 @@ ssize_t ib_uverbs_modify_qp(struct ib_uverbs_file *file, if (copy_from_user(&cmd, buf, sizeof cmd)) return -EFAULT; + if (cmd.port_num < rdma_start_port(ib_dev) || + cmd.port_num > rdma_end_port(ib_dev)) + return -EINVAL; + INIT_UDATA(&udata, buf + sizeof cmd, NULL, in_len - sizeof cmd, out_len); @@ -2882,6 +2886,10 @@ ssize_t ib_uverbs_create_ah(struct ib_uverbs_file *file, if (copy_from_user(&cmd, buf, sizeof cmd)) return -EFAULT; + if (cmd.attr.port_num < rdma_start_port(ib_dev) || + cmd.attr.port_num > rdma_end_port(ib_dev)) + return -EINVAL; + uobj = kmalloc(sizeof *uobj, GFP_KERNEL); if (!uobj) return -ENOMEM; -- 2.20.1