[ Upstream commit 6e455f5dcdd15fa28edf0ffb5b44d3508512dccf ]
Commit 3823119b9c2b ("drm/crtc: Fix uninit-value bug in
drm_mode_setcrtc") was supposed to fix use of an uninitialized variable,
but introduced another.
num_connectors is only initialized if crtc_req->count_connectors > 0,
but it's used regardless. Fix it.
Fixes: 3823119b9c2b ("drm/crtc: Fix uninit-value bug in drm_mode_setcrtc")
Cc: syzbot+4fad2e57beb6397ab2fc@syzkaller.appspotmail.com
Cc: Ziqi Zhao <astrajoan@yahoo.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Maxime Ripard <mripard@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20231208131238.2924571-1-jani.nikula@intel.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 3823119b9c2b5f9e9b760336f75bc989b805cde6 ]
The connector_set contains uninitialized values when allocated with
kmalloc_array. However, in the "out" branch, the logic assumes that any
element in connector_set would be equal to NULL if failed to
initialize, which causes the bug reported by Syzbot. The fix is to use
an extra variable to keep track of how many connectors are initialized
indeed, and use that variable to decrease any refcounts in the "out"
branch.
Reported-by: syzbot+4fad2e57beb6397ab2fc@syzkaller.appspotmail.com
Signed-off-by: Ziqi Zhao <astrajoan@yahoo.com>
Reported-and-tested-by: syzbot+4fad2e57beb6397ab2fc@syzkaller.appspotmail.com
Tested-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
Link: https://lore.kernel.org/r/20230721161446.8602-1-astrajoan@yahoo.com
Signed-off-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
