RDMA/ucm: Mark UCM interface as BROKEN

In commit 357d23c811a7 ("Remove the obsolete libibcm library")
in rdma-core [1], we removed obsolete library which used the
/dev/infiniband/ucmX interface.

Following multiple syzkaller reports about non-sanitized
user input in the UCMA module, the short audit reveals the same
issues in UCM module too.

It is better to disable this interface in the kernel,
before syzkaller team invests time and energy to harden
this unused interface.

[1] https://github.com/linux-rdma/rdma-core/pull/279

Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

diff --git a/drivers/infiniband/Kconfig b/drivers/infiniband/Kconfig
index 2a972ed6851b2265ae89ee44f621e7ee4ba174da..b03af54367c09e3b30a7617e6314116c7252be8a 100644 (file)
--- a/drivers/infiniband/Kconfig
+++ b/drivers/infiniband/Kconfig
@@ -35,6 +35,17 @@ config INFINIBAND_USER_ACCESS
          libibverbs, libibcm and a hardware driver library from
          rdma-core <https://github.com/linux-rdma/rdma-core>.
 
+config INFINIBAND_USER_ACCESS_UCM
+       bool "Userspace CM (UCM, DEPRECATED)"
+       depends on BROKEN
+       depends on INFINIBAND_USER_ACCESS
+       help
+         The UCM module has known security flaws, which no one is
+         interested to fix. The user-space part of this code was
+         dropped from the upstream a long time ago.
+
+         This option is DEPRECATED and planned to be removed.
+
 config INFINIBAND_EXP_LEGACY_VERBS_NEW_UAPI
        bool "Allow experimental legacy verbs in new ioctl uAPI  (EXPERIMENTAL)"
        depends on INFINIBAND_USER_ACCESS

diff --git a/drivers/infiniband/core/Makefile b/drivers/infiniband/core/Makefile
index 1cfedc469b23a1fb16f3b1dee02185a0ad05adad..8d42373a2d8a92e1ea7edfd240e73b5e25218890 100644 (file)
--- a/drivers/infiniband/core/Makefile
+++ b/drivers/infiniband/core/Makefile
@@ -5,8 +5,8 @@ user_access-$(CONFIG_INFINIBAND_ADDR_TRANS)     := rdma_ucm.o
 obj-$(CONFIG_INFINIBAND) +=            ib_core.o ib_cm.o iw_cm.o \
                                        $(infiniband-y)
 obj-$(CONFIG_INFINIBAND_USER_MAD) +=   ib_umad.o
-obj-$(CONFIG_INFINIBAND_USER_ACCESS) +=        ib_uverbs.o ib_ucm.o \
-                                       $(user_access-y)
+obj-$(CONFIG_INFINIBAND_USER_ACCESS) += ib_uverbs.o $(user_access-y)
+obj-$(CONFIG_INFINIBAND_USER_ACCESS_UCM) += ib_ucm.o $(user_access-y)
 
 ib_core-y :=                   packer.o ud_header.o verbs.o cq.o rw.o sysfs.o \
                                device.o fmr_pool.o cache.o netlink.o \