[Mesa-dev] [PATCH] xf86drm: Fix error path in drmGetDevice2

[Christoph Haag]

I've reported this here:
https://bugs.freedesktop.org/show_bug.cgi?id=107384

The patch in the comments initializing drmDevicePtr device to NULL makes
it work properly for me.

I don't think the patch is on the mailing list yet. It's probably a good
idea to check if there are more places where this initialization needs
to be done...


On 29.07.2018 10:20, Mariusz Ceier wrote:
> In drmGetDevice2 when no local device is found or when
> drm_device_has_rdev filters out all devices, *device might be left
> uninitialized causing drmGetDevice2 to not return error - since
> it's only returned when *device == NULL.
> 
> Above leads to crash in the firefox in system with amdgpu.
> 
> With this change firefox displays:
> 
> libGL error: MESA-LOADER: failed to retrieve device information
> libGL error: unable to load driver: amdgpu_dri.so
> libGL error: driver pointer missing
> libGL error: failed to load driver: amdgpu
> libGL error: MESA-LOADER: failed to retrieve device information
> libGL error: unable to load driver: amdgpu_dri.so
> libGL error: driver pointer missing
> libGL error: failed to load driver: amdgpu
> 
> and doesn't crash.
> 
> Signed-off-by: Mariusz Ceier <mceier+mesa-dev at gmail.com>
> ---
>  xf86drm.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/xf86drm.c b/xf86drm.c
> index 1e621e99..336d64de 100644
> --- a/xf86drm.c
> +++ b/xf86drm.c
> @@ -3935,6 +3935,8 @@ int drmGetDevice2(int fd, uint32_t flags, drmDevicePtr *device)
>  
>      drmFoldDuplicatedDevices(local_devices, node_count);
>  
> +    *device = NULL;
> +
>      for (i = 0; i < node_count; i++) {
>          if (!local_devices[i])
>              continue;
>