Am 06.07.23 um 07:52 schrieb Dan Carpenter:

The __dma_fence_unwrap_merge() function is supposed to return NULL on error. But the dma_fence_allocate_private_stub() returns error pointers so check for that and covert the error pointers to NULL returns. Otherwise, the callers do not expect error pointers and it leads to an Oops.

Oh, good catch.

But I think we should probably change dma_fence_allocate_private_stub() instead, that this function returns an ERR_PTR doesn't seem to make to much sense.

Christian.

Fixes: f781f661e8c9 ("dma-buf: keep the signaling time of merged fences v3") Signed-off-by: Dan Carpenter dan.carpenter@linaro.org

---

drivers/dma-buf/dma-fence-unwrap.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/dma-buf/dma-fence-unwrap.c b/drivers/dma-buf/dma-fence-unwrap.c index c625bb2b5d56..d183eda0db89 100644 --- a/drivers/dma-buf/dma-fence-unwrap.c +++ b/drivers/dma-buf/dma-fence-unwrap.c @@ -94,8 +94,12 @@ struct dma_fence *__dma_fence_unwrap_merge(unsigned int num_fences, * If we couldn't find a pending fence just return a private signaled * fence with the timestamp of the last signaled one. */

• if (count == 0)

• return dma_fence_allocate_private_stub(timestamp);
  

• if (count == 0) {

• tmp = dma_fence_allocate_private_stub(timestamp);
  

• if (IS_ERR(tmp))
  

• 	return NULL;
  

• return tmp;
  

• }

array = kmalloc_array(count, sizeof(*array), GFP_KERNEL); if (!array) @@ -176,6 +180,8 @@ struct dma_fence *__dma_fence_unwrap_merge(unsigned int num_fences, return_tmp: kfree(array);

• if (IS_ERR(tmp))

• return NULL;
  

  return tmp; } EXPORT_SYMBOL_GPL(__dma_fence_unwrap_merge);