If a mux clock is initialised (by hardware or firmware) with an invalid parent, its ->get_parent() can return an out of range index. For example, the generic mux clock attempts to return -EINVAL, which due to the u8 return type ends up a rather large number. Using this index with the parent_names[] array results in an invalid pointer and (usually) a crash in the following strcmp().
This patch adds a check for the parent index being in range, ignoring clocks reporting invalid values. Signed-off-by: Mans Rullgard <[email protected]> Cc: Rhyland Klein <[email protected]> --- drivers/clk/clk.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index d48ac71..bc0662b 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -1950,7 +1950,8 @@ int __clk_init(struct device *dev, struct clk *clk) hlist_for_each_entry_safe(orphan, tmp2, &clk_orphan_list, child_node) { if (orphan->num_parents && orphan->ops->get_parent) { i = orphan->ops->get_parent(orphan->hw); - if (!strcmp(clk->name, orphan->parent_names[i])) + if (i >= 0 && i < orphan->num_parents && + !strcmp(clk->name, orphan->parent_names[i])) __clk_reparent(orphan, clk); continue; } -- 2.3.0 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
