From: Jason Gunthorpe <jgg@xxxxxxxxxxxx>
[ Upstream commit 6e051971b0e2eeb0ce7ec65d3cc8180450512d36 ]
siw_fastreg_mr() invokes siw_mem_id2obj(), which returns a local reference
of the siw_mem object to "mem" with increased refcnt. When
siw_fastreg_mr() returns, "mem" becomes invalid, so the refcount should be
decreased to keep refcount balanced.
The issue happens in one error path of siw_fastreg_mr(). When "base_mr"
equals to NULL but "mem" is not NULL, the function forgets to decrease the
refcnt increased by siw_mem_id2obj() and causes a refcnt leak.
Reorganize the flow so that the goto unwind can be used as expected.
Fixes: b9be6f18cf9e ("rdma/siw: transmit path")
Link: https://lore.kernel.org/r/1586939949-69856-1-git-send-email-xiyuyang19@xxxxxxxxxxxx
Reported-by: Xiyu Yang <xiyuyang19@xxxxxxxxxxxx>
Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/infiniband/sw/siw/siw_qp_tx.c | 15 +++++++++++----
1 file changed, 11 insertions(+), 4 deletions(-)
diff --git a/drivers/infiniband/sw/siw/siw_qp_tx.c b/drivers/infiniband/sw/siw/siw_qp_tx.c
index ae92c8080967c..9f53aa4feb878 100644
--- a/drivers/infiniband/sw/siw/siw_qp_tx.c
+++ b/drivers/infiniband/sw/siw/siw_qp_tx.c
@@ -920,20 +920,27 @@ static int siw_fastreg_mr(struct ib_pd *pd, struct siw_sqe *sqe)
{
struct ib_mr *base_mr = (struct ib_mr *)(uintptr_t)sqe->base_mr;
struct siw_device *sdev = to_siw_dev(pd->device);
- struct siw_mem *mem = siw_mem_id2obj(sdev, sqe->rkey >> 8);
+ struct siw_mem *mem;
int rv = 0;
siw_dbg_pd(pd, "STag 0x%08x\n", sqe->rkey);
- if (unlikely(!mem || !base_mr)) {
+ if (unlikely(!base_mr)) {
pr_warn("siw: fastreg: STag 0x%08x unknown\n", sqe->rkey);
return -EINVAL;
}
+
if (unlikely(base_mr->rkey >> 8 != sqe->rkey >> 8)) {
pr_warn("siw: fastreg: STag 0x%08x: bad MR\n", sqe->rkey);
- rv = -EINVAL;
- goto out;
+ return -EINVAL;
}
+
+ mem = siw_mem_id2obj(sdev, sqe->rkey >> 8);
+ if (unlikely(!mem)) {
+ pr_warn("siw: fastreg: STag 0x%08x unknown\n", sqe->rkey);
+ return -EINVAL;
+ }
+
if (unlikely(mem->pd != pd)) {
pr_warn("siw: fastreg: PD mismatch\n");
rv = -EINVAL;
--
2.20.1
