The driver may sleep under a spin lock, and the function call path is:
post_one_send (acquire the lock by spin_lock_irqsave)
init_send_wqe
copy_from_user --> may sleep
There is no flow that makes "qp->is_user" true, and copy_from_user may
cause bug when a non-user pointer is used. So, the line of copy_from_user
is removed.
Signed-off-by: Jia-Ju Bai <baijiaju1...@163.com>
---
V4:
* Remove the line of copy_from_user.
V3:
* It corrects the mistakes of remaining legacy code in V2.
(Thank Ram for pointing it out)
V2:
* The parameter "flags" is added to restore and save the irq status.
Thank Leon for good advice.
---
drivers/infiniband/sw/rxe/rxe_verbs.c | 6 +-----
1 file changed, 1 insertion(+), 5 deletions(-)
diff --git a/drivers/infiniband/sw/rxe/rxe_verbs.c
b/drivers/infiniband/sw/rxe/rxe_verbs.c
index 83d709e..7c52c7c 100644
--- a/drivers/infiniband/sw/rxe/rxe_verbs.c
+++ b/drivers/infiniband/sw/rxe/rxe_verbs.c
@@ -740,11 +740,7 @@ static int init_send_wqe(struct rxe_qp *qp, struct
ib_send_wr *ibwr,
sge = ibwr->sg_list;
for (i = 0; i < num_sge; i++, sge++) {
- if (qp->is_user && copy_from_user(p, (__user void *)
- (uintptr_t)sge->addr, sge->length))
- return -EFAULT;
-
- else if (!qp->is_user)
+ if (!qp->is_user)
memcpy(p, (void *)(uintptr_t)sge->addr,
sge->length);
--
1.7.9.5
