4.9-stable review patch. If anyone has any objections, please let me know.
------------------
[ Upstream commit 6b9f8970cd30929cb6b372fa44fa66da9e59c650 ]
If the allocation of elem fails, it is not sufficient to simply check for NULL and return. We need to also put our reference on the pool or else we will leave the pool with a permanent ref count and we will never be able to free it.
Fixes: 4831ca9e4a8e ("IB/rxe: check for allocation failure on elem") Suggested-by: Leon Romanovsky leon@kernel.org Signed-off-by: Doug Ledford dledford@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/infiniband/sw/rxe/rxe_pool.c | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-)
diff --git a/drivers/infiniband/sw/rxe/rxe_pool.c b/drivers/infiniband/sw/rxe/rxe_pool.c index 1c4e5b2e6835..527ca662da69 100644 --- a/drivers/infiniband/sw/rxe/rxe_pool.c +++ b/drivers/infiniband/sw/rxe/rxe_pool.c @@ -402,23 +402,25 @@ void *rxe_alloc(struct rxe_pool *pool)
kref_get(&pool->rxe->ref_cnt);
- if (atomic_inc_return(&pool->num_elem) > pool->max_elem) { - atomic_dec(&pool->num_elem); - rxe_dev_put(pool->rxe); - rxe_pool_put(pool); - return NULL; - } + if (atomic_inc_return(&pool->num_elem) > pool->max_elem) + goto out_put_pool;
elem = kmem_cache_zalloc(pool_cache(pool), (pool->flags & RXE_POOL_ATOMIC) ? GFP_ATOMIC : GFP_KERNEL); if (!elem) - return NULL; + goto out_put_pool;
elem->pool = pool; kref_init(&elem->ref_cnt);
return elem; + +out_put_pool: + atomic_dec(&pool->num_elem); + rxe_dev_put(pool->rxe); + rxe_pool_put(pool); + return NULL; }
void rxe_elem_release(struct kref *kref)