2021-05-14 19:25:23

by Colin King

Subject: [PATCH][V2][next] drm/vmwgfx: Fix memory allocation check and a leak of object fifo

From: Colin Ian King <[email protected]>

The allocation of fifo is lacking an allocation failure check, so
fix this by adding one.

In the case where fifo->static_buffer fails to be allocated the
error return path neglects to kfree the fifo object. Fix this by
adding in the missing kfree.

Kudos to Dan Carpenter for spotting the missing kzalloc failure
check.

Addresses-Coverity: ("Resource leak")
Fixes: 2cd80dbd3551 ("drm/vmwgfx: Add basic support for SVGA3")
Signed-off-by: Colin Ian King <[email protected]>
---

V2: Add missing allocation failure check
Update $SUBJECT to reflect this extra change

---
drivers/gpu/drm/vmwgfx/vmwgfx_cmd.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_cmd.c b/drivers/gpu/drm/vmwgfx/vmwgfx_cmd.c
index 027d7d504e78..d9acd2f3f673 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_cmd.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_cmd.c
@@ -105,10 +105,14 @@ struct vmw_fifo_state *vmw_fifo_create(struct vmw_private *dev_priv)
return NULL;

fifo = kzalloc(sizeof(*fifo), GFP_KERNEL);
+ if (!fifo)
+ return ERR_PTR(-ENOMEM);
fifo->static_buffer_size = VMWGFX_FIFO_STATIC_SIZE;
fifo->static_buffer = vmalloc(fifo->static_buffer_size);
- if (unlikely(fifo->static_buffer == NULL))
+ if (unlikely(fifo->static_buffer == NULL)) {
+ kfree(fifo);
return ERR_PTR(-ENOMEM);
+ }

fifo->dynamic_buffer = NULL;
fifo->reserved_size = 0;
--
2.30.2

2021-05-14 20:20:23

by Zack Rusin

Subject: Re: [PATCH][V2][next] drm/vmwgfx: Fix memory allocation check and a leak of object fifo

On 5/14/21 10:49 AM, Colin King wrote:
> From: Colin Ian King <[email protected]>
>
> The allocation of fifo is lacking an allocation failure check, so
> fix this by adding one.
>
> In the case where fifo->static_buffer fails to be allocated the
> error return path neglects to kfree the fifo object. Fix this by
> adding in the missing kfree.
>
> Kudos to Dan Carpenter for spotting the missing kzalloc failure
> check.
>
> Addresses-Coverity: ("Resource leak")
> Fixes: 2cd80dbd3551 ("drm/vmwgfx: Add basic support for SVGA3")
> Signed-off-by: Colin Ian King <[email protected]>
> ---
>
> V2: Add missing allocation failure check
> Update $SUBJECT to reflect this extra change

Looks good. Thanks. I'll push it through drm-misc-next.

z