From cbdd2663f4c801ad93f7111f93d9846589a0d530 Mon Sep 17 00:00:00 2001 From: Colin Ian King Date: Sat, 22 Dec 2018 13:00:46 +0000 Subject: drm: fix null pointer dereference on null state pointer In the case where state cannot be allocated, the current exit path via label 'out' will dereference the null state pointer when calling drm_atomic_state_put. Fix this by adding a new error exit label and jumping to this to avoid the drm_atomic_state_put. Detected by CoverityScan, CID#1476034 ("Dereference after null check") Fixes: b9fc5e01d1ce ("drm: Add helper to implement legacy dirtyfb") Signed-off-by: Colin Ian King Signed-off-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/20181222130046.14083-1-colin.king@canonical.com --- drivers/gpu/drm/drm_damage_helper.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/drm_damage_helper.c b/drivers/gpu/drm/drm_damage_helper.c index d2a1c7372f36..31032407254d 100644 --- a/drivers/gpu/drm/drm_damage_helper.c +++ b/drivers/gpu/drm/drm_damage_helper.c @@ -178,7 +178,7 @@ int drm_atomic_helper_dirtyfb(struct drm_framebuffer *fb, state = drm_atomic_state_alloc(fb->dev); if (!state) { ret = -ENOMEM; - goto out; + goto out_drop_locks; } state->acquire_ctx = &ctx; @@ -238,6 +238,7 @@ out: kfree(rects); drm_atomic_state_put(state); +out_drop_locks: drm_modeset_drop_locks(&ctx); drm_modeset_acquire_fini(&ctx); -- cgit v1.2.3