To be honest I think the if(WARN_ON(!dmabuf)) return -EINVAL handling
here is misleading in the first place.
Returning -EINVAL on a hard coding error is not good practice and should
probably be removed from the DMA-buf subsystem in general.
Christian.
Am 18.08.21 um 13:58 schrieb Nuno Sá:
On top of warning about a NULL object, we also want to return with a
proper error code (as done in 'dma_buf_begin_cpu_access()'). Otherwise,
we will get a NULL pointer dereference.
Fixes: fc13020e086b ("dma-buf: add support for kernel cpu access")
Signed-off-by: Nuno Sá <nuno.sa@xxxxxxxxxx>
---
drivers/dma-buf/dma-buf.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c
index 63d32261b63f..8ec7876dd523 100644
--- a/drivers/dma-buf/dma-buf.c
+++ b/drivers/dma-buf/dma-buf.c
@@ -1231,7 +1231,8 @@ int dma_buf_end_cpu_access(struct dma_buf *dmabuf,
{
int ret = 0;
- WARN_ON(!dmabuf);
+ if (WARN_ON(!dmabuf))
+ return -EINVAL;
might_lock(&dmabuf->resv->lock.base);
