From bf47b4fd8f9f81cd5ce40e1945c6334d088226d1 Mon Sep 17 00:00:00 2001 From: Pawel Moll Date: Fri, 8 Jun 2012 14:04:06 +0100 Subject: [PATCH] clk: Check parent for NULL in clk_change_rate clk_change_rate() is accessing parent's rate without checking if the parent exists at all. In case of root clocks this will cause NULL pointer dereference. This patch follows what clk_calc_new_rates() does in such situation. Signed-off-by: Pawel Moll Signed-off-by: Mike Turquette Cc: stable@kernel.org --- drivers/clk/clk.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index df89cbfc1bd0..dcbe05616090 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -850,18 +850,21 @@ static void clk_change_rate(struct clk *clk) { struct clk *child; unsigned long old_rate; + unsigned long best_parent_rate = 0; struct hlist_node *tmp; old_rate = clk->rate; + if (clk->parent) + best_parent_rate = clk->parent->rate; + if (clk->ops->set_rate) - clk->ops->set_rate(clk->hw, clk->new_rate, clk->parent->rate); + clk->ops->set_rate(clk->hw, clk->new_rate, best_parent_rate); if (clk->ops->recalc_rate) - clk->rate = clk->ops->recalc_rate(clk->hw, - clk->parent->rate); + clk->rate = clk->ops->recalc_rate(clk->hw, best_parent_rate); else - clk->rate = clk->parent->rate; + clk->rate = best_parent_rate; if (clk->notifier_count && old_rate != clk->rate) __clk_notify(clk, POST_RATE_CHANGE, old_rate, clk->rate); -- 2.20.1