drm/omap: fix possible NULL ref issue in tiler_reserve_2d

[ Upstream commit 6a0f0c55619f0b82a677cab72e77c3444a5eee58 ]

tiler_reserve_2d allocates memory but does not check if it got the
memory. Add the check and return ENOMEM on failure.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180329104038.29154-2-tomi.valkeinen@ti.com
Reviewed-by: Emil Velikov <emil.velikov@collabora.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/gpu/drm/omapdrm/omap_dmm_tiler.c b/drivers/gpu/drm/omapdrm/omap_dmm_tiler.c
index 4be0c94673f5917282944a3b8e93fde6edc7f62f..17d1baee522ba039015149bd23cc4237c1db79ec 100644 (file)
--- a/drivers/gpu/drm/omapdrm/omap_dmm_tiler.c
+++ b/drivers/gpu/drm/omapdrm/omap_dmm_tiler.c
@@ -401,12 +401,16 @@ int tiler_unpin(struct tiler_block *block)
 struct tiler_block *tiler_reserve_2d(enum tiler_fmt fmt, uint16_t w,
                uint16_t h, uint16_t align)
 {
-       struct tiler_block *block = kzalloc(sizeof(*block), GFP_KERNEL);
+       struct tiler_block *block;
        u32 min_align = 128;
        int ret;
        unsigned long flags;
        u32 slot_bytes;
 
+       block = kzalloc(sizeof(*block), GFP_KERNEL);
+       if (!block)
+               return ERR_PTR(-ENOMEM);
+
        BUG_ON(!validfmt(fmt));
 
        /* convert width/height to slots */