From b3049d3d0688b1647cba4a129b156a510dbbb0b4 Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Tue, 9 Jan 2018 23:03:46 +0300 Subject: [PATCH] IB/hfi1: Prevent a NULL dereference commit 57194fa763bfa1a0908f30d4c77835beaa118fcb upstream. In the original code, we set "fd->uctxt" to NULL and then dereference it which will cause an Oops. Fixes: f2a3bc00a03c ("IB/hfi1: Protect context array set/clear with spinlock") Signed-off-by: Dan Carpenter Reviewed-by: Michael J. Ruhl Signed-off-by: Doug Ledford Signed-off-by: Greg Kroah-Hartman --- drivers/infiniband/hw/hfi1/file_ops.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/infiniband/hw/hfi1/file_ops.c b/drivers/infiniband/hw/hfi1/file_ops.c index d9a1e9893136..fd28f09b4445 100644 --- a/drivers/infiniband/hw/hfi1/file_ops.c +++ b/drivers/infiniband/hw/hfi1/file_ops.c @@ -881,11 +881,11 @@ static int complete_subctxt(struct hfi1_filedata *fd) } if (ret) { - hfi1_rcd_put(fd->uctxt); - fd->uctxt = NULL; spin_lock_irqsave(&fd->dd->uctxt_lock, flags); __clear_bit(fd->subctxt, fd->uctxt->in_use_ctxts); spin_unlock_irqrestore(&fd->dd->uctxt_lock, flags); + hfi1_rcd_put(fd->uctxt); + fd->uctxt = NULL; } return ret; -- 2.20.1