From f927767978d201d4ac023fcd797adbb963a6565d Mon Sep 17 00:00:00 2001
From: Maxime Ripard <maxime@cerno.tech>
Date: Wed, 17 Nov 2021 10:45:23 +0100
Subject: [PATCH] drm/vc4: kms: Fix return code check
Git-commit: f927767978d201d4ac023fcd797adbb963a6565d
Patch-mainline: v5.16-rc4
References: git-fixes
The HVS global state functions return an error pointer, but in most
cases we check if it's NULL, possibly resulting in an invalid pointer
dereference.
Fixes: 9ec03d7f1ed3 ("drm/vc4: kms: Wait on previous FIFO users before a commit")
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Tested-by: Jian-Hong Pan <jhp@endlessos.org>
Link: https://lore.kernel.org/r/20211117094527.146275-3-maxime@cerno.tech
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/gpu/drm/vc4/vc4_kms.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)
diff --git a/drivers/gpu/drm/vc4/vc4_kms.c b/drivers/gpu/drm/vc4/vc4_kms.c
index 764ddb41a4ce..3f780c195749 100644
--- a/drivers/gpu/drm/vc4/vc4_kms.c
+++ b/drivers/gpu/drm/vc4/vc4_kms.c
@@ -354,7 +354,7 @@ static void vc4_atomic_commit_tail(struct drm_atomic_state *state)
}
old_hvs_state = vc4_hvs_get_old_global_state(state);
- if (!old_hvs_state)
+ if (IS_ERR(old_hvs_state))
return;
for_each_old_crtc_in_state(state, crtc, old_crtc_state, i) {
@@ -410,8 +410,8 @@ static int vc4_atomic_commit_setup(struct drm_atomic_state *state)
unsigned int i;
hvs_state = vc4_hvs_get_new_global_state(state);
- if (!hvs_state)
- return -EINVAL;
+ if (WARN_ON(IS_ERR(hvs_state)))
+ return PTR_ERR(hvs_state);
for_each_new_crtc_in_state(state, crtc, crtc_state, i) {
struct vc4_crtc_state *vc4_crtc_state =
@@ -762,8 +762,8 @@ static int vc4_pv_muxing_atomic_check(struct drm_device *dev,
unsigned int i;
hvs_new_state = vc4_hvs_get_global_state(state);
- if (!hvs_new_state)
- return -EINVAL;
+ if (IS_ERR(hvs_new_state))
+ return PTR_ERR(hvs_new_state);
for (i = 0; i < ARRAY_SIZE(hvs_new_state->fifo_state); i++)
if (!hvs_new_state->fifo_state[i].in_use)
--
2.31.1