vulkan/wsi/x11: fix shm allocation control flow issue

shmget returns -1 on error. alloc_shm assigns it to an unsigned variable
and then checks whether it's < 0, which will never be true.

Found by Coverity.
CID: 1490891

Fixes: 1f55f9a97a5 ("vulkan/wsi/sw: add support for using host_ptr for shm pixmaps.")

Signed-off-by: Marcin Ślusarz <marcin.slusarz@intel.com>
Reviewed-by: Dave Airlie <airlied@redhat.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/12696>

diff --git a/src/vulkan/wsi/wsi_common_x11.c b/src/vulkan/wsi/wsi_common_x11.c
index bb6adeb..fcda05d 100644 (file)
--- a/src/vulkan/wsi/wsi_common_x11.c
+++ b/src/vulkan/wsi/wsi_common_x11.c
@@ -834,7 +834,7 @@ struct x11_image {
    uint32_t                                  sync_fence;
    uint32_t                                  serial;
    xcb_shm_seg_t                             shmseg;
-   uint32_t                                  shmid;
+   int                                       shmid;
    uint8_t *                                 shmaddr;
 };