4.14-stable review patch. If anyone has any objections, please let me know.
------------------
From: Jason Gunthorpe <jgg@xxxxxxxxxxxx>
[ Upstream commit ec6f8401c48a86809237e86878a6fac6b281118f ]
If remove_commit fails then the lock is left locked while the uobj still
exists. Eventually the kernel will deadlock.
lockdep detects this and says:
test/4221 is leaving the kernel with locks still held!
1 lock held by test/4221:
#0: (&ucontext->cleanup_rwsem){.+.+}, at: [<000000001e5c7523>] rdma_explicit_destroy+0x37/0x120 [ib_uverbs]
Fixes: 4da70da23e9b ("IB/core: Explicitly destroy an object while keeping uobject")
Signed-off-by: Leon Romanovsky <leon@xxxxxxxxxx>
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@xxxxxxxxx>
Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/infiniband/core/rdma_core.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
--- a/drivers/infiniband/core/rdma_core.c
+++ b/drivers/infiniband/core/rdma_core.c
@@ -486,12 +486,13 @@ int rdma_explicit_destroy(struct ib_uobj
ret = uobject->type->type_class->remove_commit(uobject,
RDMA_REMOVE_DESTROY);
if (ret)
- return ret;
+ goto out;
uobject->type = &null_obj_type;
+out:
up_read(&ucontext->cleanup_rwsem);
- return 0;
+ return ret;
}
static void alloc_commit_idr_uobject(struct ib_uobject *uobj)
