From: Xiaomeng Tong xiam0nd.tong@gmail.com
stable inclusion from stable-v5.10.121 commit 591c3481b13fa6d5d03819e90539fa442c6ed2d2 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I5L6CQ
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
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commit bdef417d84536715145f6dc9cc3275c46f26295a upstream.
The bug is here: return crtc;
The list iterator value 'crtc' will *always* be set and non-NULL by list_for_each_entry(), so it is incorrect to assume that the iterator value will be NULL if the list is empty or no element is found.
To fix the bug, return 'crtc' when found, otherwise return NULL.
Cc: stable@vger.kernel.org fixes: 89c78134cc54d ("gma500: Add Poulsbo support") Signed-off-by: Xiaomeng Tong xiam0nd.tong@gmail.com Signed-off-by: Patrik Jakobsson patrik.r.jakobsson@gmail.com Link: https://patchwork.freedesktop.org/patch/msgid/20220327052028.2013-1-xiam0nd.... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com Acked-by: Xie XiuQi xiexiuqi@huawei.com --- drivers/gpu/drm/gma500/psb_intel_display.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/gma500/psb_intel_display.c b/drivers/gpu/drm/gma500/psb_intel_display.c index 531c5485be17..bd3df5adb96f 100644 --- a/drivers/gpu/drm/gma500/psb_intel_display.c +++ b/drivers/gpu/drm/gma500/psb_intel_display.c @@ -536,14 +536,15 @@ void psb_intel_crtc_init(struct drm_device *dev, int pipe,
struct drm_crtc *psb_intel_get_crtc_from_pipe(struct drm_device *dev, int pipe) { - struct drm_crtc *crtc = NULL; + struct drm_crtc *crtc;
list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) { struct gma_crtc *gma_crtc = to_gma_crtc(crtc); + if (gma_crtc->pipe == pipe) - break; + return crtc; } - return crtc; + return NULL; }
int gma_connector_clones(struct drm_device *dev, int type_mask)