Commit bf47b4fd8f9f81cd5ce40e1945c6334d088226d1 upstream. 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 <[email protected]> Signed-off-by: Mike Turquette <[email protected]> --- drivers/clk/clk.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index 9cf6f59..5e0f9a7 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -834,18 +834,21 @@ 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); 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); -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
