diff options
author | Thomas Zimmermann <tzimmermann@suse.de> | 2022-02-09 19:16:13 +0300 |
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committer | Thomas Zimmermann <tzimmermann@suse.de> | 2022-02-10 16:48:50 +0300 |
commit | a3c286dcef7f8bc576a20f5d1e80624f6b4b93ee (patch) | |
tree | 00a2164d7302a82850a95869f3a7b08e0b395912 /drivers/gpu/drm/drm_fb_helper.c | |
parent | f5666d482305900b9622a2c9dd73a864a3b0d281 (diff) | |
download | linux-a3c286dcef7f8bc576a20f5d1e80624f6b4b93ee.tar.xz |
drm/fb-helper: Fix clip rectangle height
Computing the clip rectangle is prone to off-by-one errors when writes
happen near the end of a memory page. Point the end of the memory area
to the first trailing byte, so that (end - start) returns the area's
length.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220209161617.3553-2-tzimmermann@suse.de
Diffstat (limited to 'drivers/gpu/drm/drm_fb_helper.c')
-rw-r--r-- | drivers/gpu/drm/drm_fb_helper.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c index f15127a32f7a..a37fb4a980c8 100644 --- a/drivers/gpu/drm/drm_fb_helper.c +++ b/drivers/gpu/drm/drm_fb_helper.c @@ -699,7 +699,7 @@ void drm_fb_helper_deferred_io(struct fb_info *info, max = 0; list_for_each_entry(page, pagelist, lru) { start = page->index << PAGE_SHIFT; - end = start + PAGE_SIZE - 1; + end = start + PAGE_SIZE; min = min(min, start); max = max(max, end); } |