From: Zijun Hu quic_zijuhu@quicinc.com
if the node @out_irq->np got by of_irq_parse_raw() is a combo node which consists of both controller and nexus, namely, of_irq_parse_raw() returns due to condition (@ipar == @newpar), then the node's refcount was increased twice, hence causes refcount leakage.
Fix by putting @out_irq->np refcount before returning due to the condition. Also add comments about refcount of node @out_irq->np got by the API.
Fixes: 041284181226 ("of/irq: Allow matching of an interrupt-map local to an interrupt controller") Cc: stable@vger.kernel.org Signed-off-by: Zijun Hu quic_zijuhu@quicinc.com --- drivers/of/irq.c | 8 ++++++++ 1 file changed, 8 insertions(+)
diff --git a/drivers/of/irq.c b/drivers/of/irq.c index d88719c316a3931502c34a65b2db8921f7528d99..c41b2533d86d8eceabe8f2e43842af33f22febff 100644 --- a/drivers/of/irq.c +++ b/drivers/of/irq.c @@ -165,6 +165,8 @@ const __be32 *of_irq_parse_imap_parent(const __be32 *imap, int len, struct of_ph * the specifier for each map, and then returns the translated map. * * Return: 0 on success and a negative number on error + * + * Note: refcount of node @out_irq->np is increased by 1 on success. */ int of_irq_parse_raw(const __be32 *addr, struct of_phandle_args *out_irq) { @@ -310,6 +312,12 @@ int of_irq_parse_raw(const __be32 *addr, struct of_phandle_args *out_irq) addrsize = (imap - match_array) - intsize;
if (ipar == newpar) { + /* + * Has got @ipar's refcount, but the refcount was + * got again by of_irq_parse_imap_parent() via its + * alias @newpair. + */ + of_node_put(ipar); pr_debug("%pOF interrupt-map entry to self\n", ipar); return 0; }