Commit ad4b3236 authored Jul 01, 2022 by Liang He Committed by Michael Ellerman Sep 05, 2022

powerpc/cell: Add missing of_node_put()s in cbe_regs.c



There are several bugs as following:

(1) In cbe_get_be_node(), hold the reference returned by of_find_xxx and
    of_get_xxx OF APIs and use it to call of_node_put().
(2) In cbe_fill_regs_map(), same as above.
(3) In cbe_regs_init(), during the iteration of for_each_node_by_type(),
    the refcount of 'cpu' will be automatically increased and decreased.
    However, there is a reference escaped out into 'map->cpu_node' and
    it should be properly handled.

Signed-off-by: Liang He <windhl@126.com>
[mpe: Drop references before pointer equality test in cbe_get_be_node()]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220701144949.252364-1-windhl@126.com

parent d9e1c610

arch/powerpc/platforms/cell/cbe_regs.c

+27 −10

Original line number	Diff line number	Diff line
		@@ -182,10 +182,17 @@ static struct device_node *__init cbe_get_be_node(int cpu_id)
		if (WARN_ON_ONCE(!cpu_handle))
		return np;

		for (i=0; i<len; i++)
		if (of_find_node_by_phandle(cpu_handle[i]) == of_get_cpu_node(cpu_id, NULL))
		for (i = 0; i < len; i++) {
		struct device_node *ch_np = of_find_node_by_phandle(cpu_handle[i]);
		struct device_node *ci_np = of_get_cpu_node(cpu_id, NULL);

		of_node_put(ch_np);
		of_node_put(ci_np);

		if (ch_np == ci_np)
		return np;
		}
		}

		return NULL;
		}
		@@ -193,21 +200,30 @@ static struct device_node *__init cbe_get_be_node(int cpu_id)
		static void __init cbe_fill_regs_map(struct cbe_regs_map *map)
		{
		if(map->be_node) {
		struct device_node be, np;
		struct device_node be, np, *parent_np;

		be = map->be_node;

		for_each_node_by_type(np, "pervasive")
		if (of_get_parent(np) == be)
		for_each_node_by_type(np, "pervasive") {
		parent_np = of_get_parent(np);
		if (parent_np == be)
		map->pmd_regs = of_iomap(np, 0);
		of_node_put(parent_np);
		}

		for_each_node_by_type(np, "CBEA-Internal-Interrupt-Controller")
		if (of_get_parent(np) == be)
		for_each_node_by_type(np, "CBEA-Internal-Interrupt-Controller") {
		parent_np = of_get_parent(np);
		if (parent_np == be)
		map->iic_regs = of_iomap(np, 2);
		of_node_put(parent_np);
		}

		for_each_node_by_type(np, "mic-tm")
		if (of_get_parent(np) == be)
		for_each_node_by_type(np, "mic-tm") {
		parent_np = of_get_parent(np);
		if (parent_np == be)
		map->mic_tm_regs = of_iomap(np, 0);
		of_node_put(parent_np);
		}
		} else {
		struct device_node *cpu;
		/* That hack must die die die ! */
		@@ -261,7 +277,8 @@ void __init cbe_regs_init(void)
		of_node_put(cpu);
		return;
		}
		map->cpu_node = cpu;
		of_node_put(map->cpu_node);
		map->cpu_node = of_node_get(cpu);

		for_each_possible_cpu(i) {
		struct cbe_thread_map *thread = &cbe_thread_map[i];