diff options
| author | Zack Rusin <zack.rusin@broadcom.com> | 2026-05-05 18:22:26 -0400 |
|---|---|---|
| committer | Zack Rusin <zack.rusin@broadcom.com> | 2026-07-27 11:29:24 -0400 |
| commit | f739416dc555fa205a785e5135d73fa39b26f35d (patch) | |
| tree | 7c93f3fdfb7ce30f6c9a1dd25c2c3bfbe77a647f /drivers | |
| parent | 250af2e8c3e90dc978e062a936b633870a22e660 (diff) | |
drm/vmwgfx: drop dma_buf reference on foreign-fd prime import
ttm_prime_fd_to_handle() returns -ENOSYS when the imported fd's
dma_buf->ops do not match the ttm_object_device's ops, but does so
without releasing the reference acquired by dma_buf_get(). Any
unprivileged renderD client passing a non-vmwgfx prime fd through the
DRM_VMW_GB_SURFACE_REF{,_EXT} path leaks one dma_buf reference per
call and indefinitely pins the foreign exporter's GEM resources.
Funnel the error path through the existing dma_buf_put() so the
reference is always dropped.
Fixes: 65981f7681ab ("drm/ttm: Add a minimal prime implementation for ttm base objects")
Cc: stable@vger.kernel.org
Assisted-by: Claude:claude-opus-4.7
Signed-off-by: Zack Rusin <zack.rusin@broadcom.com>
Reviewed-by: Ian Forbes <ian.forbes@broadcom.com>
Link: https://patch.msgid.link/20260505222728.519626-6-zack.rusin@broadcom.com
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/gpu/drm/vmwgfx/ttm_object.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/drivers/gpu/drm/vmwgfx/ttm_object.c b/drivers/gpu/drm/vmwgfx/ttm_object.c index 2421b0dd057c..f9042bafdc93 100644 --- a/drivers/gpu/drm/vmwgfx/ttm_object.c +++ b/drivers/gpu/drm/vmwgfx/ttm_object.c @@ -547,14 +547,17 @@ int ttm_prime_fd_to_handle(struct ttm_object_file *tfile, if (IS_ERR(dma_buf)) return PTR_ERR(dma_buf); - if (dma_buf->ops != &tdev->ops) - return -ENOSYS; + if (dma_buf->ops != &tdev->ops) { + ret = -ENOSYS; + goto out; + } prime = (struct ttm_prime_object *) dma_buf->priv; base = &prime->base; *handle = base->handle; ret = ttm_ref_object_add(tfile, base, NULL, false); +out: dma_buf_put(dma_buf); return ret; |